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Title:
Effect of a low-carbohydrate, ketogenic diet program compared to a low-fat diet on fasting lipoprotein subclasses
Authors:
Westman, Eric C.; Yancy, William S.; Olsen, Maren K.; Dudley, Tara; Guyton, John R.
Abstract:
BACKGROUND: Low-carbohydrate, ketogenic diets (LCKD) are effective for weight loss, but concerns remain regarding cardiovascular risk. The purpose of this study was to determine the effect of an LCKD program on serum lipoprotein subclasses. METHODS: This was a randomized, two-arm clinical trial in an outpatient research clinic involving overweight, hyperlipidemic community volunteers motivated to lose weight. Subjects were randomized to either an LCKD (n = 59) and nutritional supplementation (including fish, borage and flaxseed oil), or a low-fat, reduced-calorie diet (LFD, n = 60). The main outcomes were fasting serum lipoprotein subclasses determined by nuclear magnetic resonance analysis. RESULTS: The mean age of subjects was 44.9 years, the mean BMI was 34.4 kg/m(2), and 76% were women. Comparing baseline to 6 months, the LCKD group had significant changes in large VLDL (-78%), medium VLDL (-60%), small VLDL (-57%), LDL particle size (+2%), large LDL (+54%), medium LDL (-42%), small LDL (-78%), HDL particle size (+5%), large HDL (+21%), and LDL particle concentration (-11%). Compared with the LFD group, the LCKD group had greater reductions in medium VLDL (p = 0.01), small VLDL (p = 0.01) and medium LDL (p = 0.02), and greater increases in VLDL particle size (p = 0.01), large LDL (p = 0.004), and HDL particle size (p = 0.05). CONCLUSIONS: The LCKD with nutritional supplementation led to beneficial changes in serum lipid subclasses during weight loss. While the LCKD did not lower total LDL cholesterol, it did result in a shift from small, dense LDL to large, buoyant LDL, which could lower cardiovascular disease risk.
Published:
June 15, 2006
Title:
A low-carbohydrate diet may prevent end-stage renal failure in type 2 diabetes. A case report
Authors:
Nielsen, Jørgen Vesti; Westerlund, Per; Bygren, Per
Abstract:
An obese patient with type 2 diabetes whose diet was changed from the recommended high-carbohydrate, low-fat type to a low-carbohydrate diet showed a significant reduction in bodyweight, improved glycemic control and a reversal of a six year long decline of renal function. The reversal of the renal function was likely caused by both improved glycemic control and elimination of the patient's obesity.
Published:
June 13, 2006
Title:
Change in Liver Size and Fat Content after Treatment with Optifast® Very Low Calorie Diet
Authors:
Lewis, Mark C.; Phillips, Madeleine L.; Slavotinek, John P.; Kow, Lilian; Thompson, Campbell H.; Toouli, Jim
Abstract:
Background: Laparoscopic adjustable gastric banding (LAGB) requires surgical access to the gastroesophageal junction, which may be compromised by the enlarged, fatty liver that is frequently encountered in the obese. Liver size appears reduced and surgical access improved following preoperative weight loss with Optifast® Very Low Calorie Diet (VLCD). The aim of this study was to assess the effects of 6 weeks Optifast® VLCD on liver volume and fat content. Methods: 18 morbidly obese subjects underwent magnetic resonance imaging and spectroscopy to measure liver size and fat content before and after intensive treatment with Optifast® VLCD for 6 weeks. Results: All subjects completing 6 weeks Optifast® VLCD lost weight. Body weight and BMI (median [interquartile range]) reduced from 119.7 [111.9-131.3] kg and 44 [40-51] kg/m2 respectively, to 110.6 [98.0124.5] kg and 40 [36-47] kg/m2, P<0.001. Median excess weight loss (EWL) was 15.1 [9.6-21.1]%. Baseline liver volume and fat content were related (r=0.633, P=0.005). After 6 weeks Optifast® VLCD, there was a 14.7% reduction in mean liver volume (P
Published:
May 31, 2006
Title:
[Attention deficit hyperactivity disorder in adults: a clinical and therapeutic characterization]
Authors:
Ramos-Quiroga, J. A.; Bosch-Munsó, R.; Castells-Cervelló, X.; Nogueira-Morais, M.; García-Gimenez, E.; Casas-Brugué, M.
Abstract:
AIM: To update the existing knowledge about attention deficit hyperactivity disorder (ADHD) in adults, with special interest given to aspects concerning epidemiology, diagnosis, progression and treatment. DEVELOPMENT: Acknowledging the fact that ADHD can persist into adulthood is a relatively recent development. Nevertheless, over the last few years evidence has been put forward to support the validity of its diagnosis in adults. The prevalence of ADHD in the general adult population is estimated to be around 4%. Over 50% of the children with the disorder will continue to have it as adults. The symptoms of ADHD can be different in adults, with less hyperactivity and a slight decrease in impulsiveness, but with the same symptoms of inattention. ADHD in adulthood is linked to serious economic, occupational, academic and familial repercussions, as well as to road accidents and to the presence of other psychiatric pathologies (such as drug addiction, personality disorders and depression). CONCLUSIONS: A number of different psychometric instruments are available in Spanish for evaluating ADHD in adults. The use of structured interviews, together with a systemized evaluation of possible comorbid disorders, makes it easier to reach a correct differential diagnostic. Pharmacological treatment in adults is essentially the same as that used with children, but weight-adjusted. Clinical trials have been carried out with psychostimulants and results show methylphenidate to be the most effective and the safest. Atomoxetine is the non-stimulating pharmaceutical that has been most widely studied in adults. Cognitive behavioural psychological treatments have proved to be effective in adults with ADHD.
Published:
May 15, 2006
Title:
The clinical relevance of the metabolism of prostate cancer; zinc and tumor suppression: connecting the dots
Authors:
Costello, Leslie C.; Franklin, Renty B.
Abstract:
The genetic and molecular mechanisms responsible for and associated specifically with the development and progression of malignant prostate cells are largely unidentified. In addition, despite its implication in virtually all malignant cells, the role of altered cellular metabolism as an essential factor in prostate malignancy has been largely ignored. Moreover, the intermediary metabolism of normal prostate as well as malignant prostate cells is among the least studied and most poorly understood of all mammalian cells. Some important factors, especially the role of zinc, have been identified and implicated in the development and progression of prostrate malignancy. In this review, we provide a current and updated integrated assessment of the relationships of intermediary metabolism in normal prostate and in prostate cancer. The experimental and clinical evidence that leads to the formulation of concepts of normal and malignant prostate metabolism is presented. The evidence for a concept of zinc as a tumor suppressor agent and Zip1 zinc transporter as a tumor-suppressor gene is described.
Published:
May 14, 2006
Title:
Effects of a carbohydrate-restricted diet on emerging plasma markers for cardiovascular disease
Authors:
Wood, Richard J.; Volek, Jeff S.; Davis, Steven R.; Dell'Ova, Carly; Fernandez, Maria Luz
Abstract:
Increasing evidence supports carbohydrate restricted diets (CRD) for weight loss and improvement in traditional markers for cardiovascular disease (CVD); less is known regarding emerging CVD risk factors. We previously reported that a weight loss intervention based on a CRD (% carbohydrate:fat:protein = 13:60:27) led to a mean weight loss of 7.5 kg and a 20% reduction of abdominal fat in 29 overweight men. This group showed reduction in plasma LDL-cholesterol and triglycerides and elevations in HDL-cholesterol as well as reductions in large and medium VLDL particles and increases in LDL particle size. In this study we report on the effect of this intervention with and without fiber supplementation on plasma homocysteine, lipoprotein (a) [Lp(a)], C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α).
Published:
May 3, 2006
Title:
Bipolar Depression: A Comprehensive Guide
Authors:
Abstract:
Although depression is the most common presentation of bipolar disorder, correct diagnosis generally requires a history of mania and thus presents a formidable challenge. This book provides clinicians with the necessary guidance to distinguish this illness and pursue an appropriate therapeutic course. It brings together a team of clinical investigators who offer cutting-edge research on the topic and address the most critical concerns regarding its treatment.Bipolar Depression first introduces a hierarchical model for diagnosis to allow the clinician to distinguish between bipolar and unipolar depression, addressing problems of misdiagnosis and overdiagnosis as well as differentiating attention-deficit/hyperactivity disorder (ADHD) and bipolar disorder. Early chapters review the neurobiology and genetics of this highly heritable condition, presenting studies of neurotransmitter function and brain imaging studies and documenting the susceptibility of specific chromosomes as loci for bipolar disorder. Other chapters address the particular issues of bipolar depression in children, for whom a diagnosis is especially problematic, and suicide, focusing on the need for assessment during both acute and maintenance treatment with interventions appropriate to a patient's symptoms and history. Bipolar Depression offers critiques of specific treatment approaches: - Lithium and antiepileptic drugs: featuring a review of the most recent research on the use of lithium, in which higher doses are shown to be effective, plus coverage of lamotrigine, valproic acid, carbamazepine, oxcarbazepine, and topiramate.- Antidepressants: offering new perspectives on a complex field, including a discussion of the randomized clinical trial literature and observational studies on their use, and citing cautions regarding side effects.- Antipsychotics: evaluating the difference between first- and second-generation medications and discussing their role in controlling acute depressions.- Novel approaches to treatment: including the use of atypical neuroleptics, electroconvulsive therapy, transcranial magnetic stimulation, vagus nerve stimulation, ketogenic diet, omega-3 fatty acids, myo-inositol, and dopamine agonists.- Psychological interventions: focusing on the inclusion of cognitive-behavioral therapy or interpersonal social rhythm therapy for nonmelancholic depressions in patients who had previously received psychoeducation. Despite the past decade's advances in practice and research, there remains much room for progress in understanding and treating bipolar depression. This book blazes a trail toward that goal, opening new doors in recognizing differences between bipolar and unipolar forms of depression while offering both researchers and clinicians key insights into this troubling illness.
Published:
May 2, 2006
Title:
Separate effects of reduced carbohydrate intake and weight loss on atherogenic dyslipidemia
Authors:
Krauss, Ronald M.; Blanche, Patricia J.; Rawlings, Robin S.; Fernstrom, Harriett S.; Williams, Paul T.
Abstract:
ABSTRACT. Background: Low-carbohydrate diets have been used to manage obesity and its metabolic consequences.Objective: The objective was to study the effects
Published:
April 30, 2006
Title:
Trans Fatty Acids and Cardiovascular Disease
Authors:
Mozaffarian, Dariush; Katan, Martijn B.; Ascherio, Alberto; Stampfer, Meir J.; Willett, Walter C.
Abstract:
The intake of trans fat has been associated with coronary heart disease, sudden death from cardiac causes, and diabetes. This article reviews the evidence for physiological and cellular effects of trans fatty acids, unsaturated fatty acids with at least one double bond in the trans configuration. The authors consider the feasibility and potential implications of reducing or eliminating the consumption of trans fatty acids from partially hydrogenated vegetable oils in the United States.
Published:
April 12, 2006
Title:
A ketogenic diet as a potential novel therapeutic intervention in amyotrophic lateral sclerosis
Authors:
Zhao, Zhong; Lange, Dale J; Voustianiouk, Andrei; MacGrogan, Donal; Ho, Lap; Suh, Jason; Humala, Nelson; Thiyagarajan, Meenakshisundaram; Wang, Jun; Pasinetti, Giulio M
Abstract:
Background The cause of neuronal death in amyotrophic lateral sclerosis (ALS) is uncertain but mitochondrial dysfunction may play an important role. Ketones promote mitochondrial energy production and membrane stabilization. Results SOD1-G93A transgenic ALS mice were fed a ketogenic diet (KD) based on known formulations for humans. Motor performance, longevity, and motor neuron counts were measured in treated and disease controls. Because mitochondrial dysfunction plays a central role in neuronal cell death in ALS, we also studied the effect that the principal ketone body, D-β-3 hydroxybutyrate (DBH), has on mitochondrial ATP generation and neuroprotection. Blood ketones were > 3.5 times higher in KD fed animals compared to controls. KD fed mice lost 50% of baseline motor performance 25 days later than disease controls. KD animals weighed 4.6 g more than disease control animals at study endpoint; the interaction between diet and change in weight was significant (p = 0.047). In spinal cord sections obtained at the study endpoint, there were more motor neurons in KD fed animals (p = 0.030). DBH prevented rotenone mediated inhibition of mitochondrial complex I but not malonate inhibition of complex II. Rotenone neurotoxicity in SMI-32 immunopositive motor neurons was also inhibited by DBH. Conclusion This is the first study showing that diet, specifically a KD, alters the progression of the clinical and biological manifestations of the G93A SOD1 transgenic mouse model of ALS. These effects may be due to the ability of ketone bodies to promote ATP synthesis and bypass inhibition of complex I in the mitochondrial respiratory chain.
Published:
April 2, 2006
Title:
Gonadal Hormones Determine Sensitivity to Central Leptin and Insulin
Authors:
Clegg, Deborah J.; Brown, Lynda M.; Woods, Stephen C.; Benoit, Stephen C.
Abstract:
Males have proportionally more visceral fat and are more likely to develop complications associated with obesity than females, and the male brain is relatively more sensitive to the catabolic action of insulin and less sensitive to that of leptin than the female brain. To understand the underlying mechanism, we manipulated estrogen through ovariectomy (OVX) and estradiol administration. Rats with relatively high systemic estrogen (intact females and OVX females and males administered estrogen subcutaneously) were significantly more sensitive to leptin’s anorexic action in the brain (i3vt), as well as significantly less sensitive to insulin’s i3vt action, than intact males. Administering estradiol directly into the brain of our females increased i3vt leptin sensitivity while decreasing i3vt insulin sensitivity and changed the body fat distribution of our females to resemble that of intact females. These data indicate that estrogen acts within the brain to increase leptin sensitivity, decrease insulin sensitivity, and favor subcutaneous over visceral fat.
Published:
March 31, 2006
Title:
Bupropion-SR, Sertraline, or Venlafaxine-XR after Failure of SSRIs for Depression
Authors:
Rush, A. John; Trivedi, Madhukar H.; Wisniewski, Stephen R.; Stewart, Jonathan W.; Nierenberg, Andrew A.; Thase, Michael E.; Ritz, Louise; Biggs, Melanie M.; Warden, Diane; Luther, James F.; Shores-Wilson, Kathy; Niederehe, George; Fava, Maurizio
Abstract:
Background After unsuccessful treatment for depression with a selective serotonin-reuptake inhibitor (SSRI), it is not known whether switching to one antidepressant is more effective than switching to another. Methods We randomly assigned 727 adult outpatients with a nonpsychotic major depressive disorder who had no remission of symptoms or could not tolerate the SSRI citalopram to receive one of the following drugs for up to 14 weeks: sustained-release bupropion (239 patients) at a maximal daily dose of 400 mg, sertraline (238 patients) at a maximal daily dose of 200 mg, or extended-release venlafaxine (250 patients) at a maximal daily dose of 375 mg. The study was conducted in 18 primary and 23 psychiatric care settings. The primary outcome was symptom remission, defined by a total score of 7 or less on the 17-item Hamilton Rating Scale for Depression (HRSD-17) at the end of the study. Scores on the Quick Inventory of Depressive Symptomatology — Self Report (QIDS-SR-16), obtained at treatment visits, determined secondary outcomes, including remission (a score of 5 or less at exit) and response (a reduction of 50 percent or more on baseline scores). Results Remission rates as assessed by the HRSD-17 and the QIDS-SR-16, respectively, were 21.3 percent and 25.5 percent for sustained-release bupropion, 17.6 percent and 26.6 percent for sertraline, and 24.8 percent and 25.0 percent for extended-release venlafaxine. QIDS-SR-16 response rates were 26.1 percent for sustained-release bupropion, 26.7 percent for sertraline, and 28.2 percent for extended-release venlafaxine. These treatments did not differ significantly with respect to outcomes, tolerability, or adverse events. From the Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas (A.J.R., M.H.T., M.M.B., D.W., K.S.-W.); the Epidemiology Data Center, Graduate School of Public Health, University of Pittsburgh (S.R.W., J.F.L.), and the Department of Psychiatry, University of Pittsburgh School of Medicine (M.E.T.) — both in Pittsburgh; the New York State Psychiatric Institute and Columbia College of Physicians and Surgeons, New York ( J.W.S.); the Clinical Psychopharmacology Unit, Massachusetts General Hospital, Boston (A.A.N., M.F.); and the National Institute of Mental Health, Bethesda, Md. (L.R., G.N.). Address reprint requests to Dr. Rush at the Department of Psychiatry, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd., Dallas, TX 75390-9086, or at john.rush@utsouthwestern.edu. *The Sequenced Treatment Alternatives to Relieve Depression (STAR*D) trial investigators are listed in the Appendix. N Engl J Med 2006;354:1231-42. Copyright © 2006 Massachusetts Medical Society. Conclusions After unsuccessful treatment with an SSRI, approximately one in four patients had a remission of symptoms after switching to another antidepressant. Any one of the medications in the study provided a reasonable second-step choice for patients with depression. (ClinicalTrials.gov number, NCT00021528.)
Published:
March 22, 2006
Title:
Modelling the extinction of Steller's sea cow
Authors:
Turvey, S. T.; Risley, C. L.
Abstract:
Steller's sea cow, a giant sirenian discovered in 1741 and extinct by 1768, is one of the few megafaunal mammal species to have died out during the historical period. The species is traditionally considered to have been exterminated by 'blitzkrieg'-style direct overharvesting for food, but it has also been proposed that its extinction resulted from a sea urchin population explosion triggered by extirpation of local sea otter populations that eliminated the shallow-water kelps on which sea cows fed. Hunting records from eighteenth century Russian expeditions to the Commander Islands, in conjunction with life-history data extrapolated from dugongs, permit modelling of sea cow extinction dynamics. Sea cows were massively and wastefully overexploited, being hunted at over seven times the sustainable limit, and suggesting that the initial Bering Island sea cow population must have been higher than suggested by previous researchers to allow the species to survive even until 1768. Environmental changes caused by sea otter declines are unlikely to have contributed to this extinction event. This indicates that megafaunal extinctions can be effected by small bands of hunters using pre-industrial technologies, and highlights the catastrophic impact of wastefulness when overexploiting resources mistakenly perceived as 'infinite'.
Published:
March 21, 2006
Title:
[Developmental delay in breastfed children due to inadequate diet of the mother]
Authors:
Baatenburg de Jong, A.; Bekhof, J.; Zwart, P.; Langenhorst, V. J.; Roorda, R. J.
Abstract:
Two infant boys of 7 and 12 months respectively who presented with symptoms of failure to thrive and developmental delay were diagnosed with vitamin B12 deficiency. This deficiency is a rare condition in infants living in developed countries. It does occur, however, in infants who are breastfed by mothers with an inadequate diet. Both of the children studied were breastfed by vegetarian mothers. Following vitamin suppletion, both children showed signs of recovery. The importance of considering vitamin deficiencies in similar infants presenting with failure to thrive is emphasized. Moreover, maternal dietary habits in breastfed children should be checked. To prevent irreversible neurological damage, early recognition of any nutritional deficiencies is important.
Published:
March 3, 2006
Title:
Thyroid status, cardiovascular risk, and mortality in older adults
Authors:
Cappola, Anne R.; Fried, Linda P.; Arnold, Alice M.; Danese, Mark D.; Kuller, Lewis H.; Burke, Gregory L.; Tracy, Russell P.; Ladenson, Paul W.
Abstract:
CONTEXT: Previous studies have suggested that subclinical abnormalities in thyroid-stimulating hormone levels are associated with detrimental effects on the cardiovascular system. OBJECTIVE: To determine the relationship between baseline thyroid status and incident atrial fibrillation, incident cardiovascular disease, and mortality in older men and women not taking thyroid medication. DESIGN, SETTING, AND PARTICIPANTS: A total of 3233 US community-dwelling individuals aged 65 years or older with baseline serum thyroid-stimulating hormone levels were enrolled in 1989-1990 in the Cardiovascular Health Study, a large, prospective cohort study. MAIN OUTCOME MEASURES: Incident atrial fibrillation, coronary heart disease, cerebrovascular disease, cardiovascular death, and all-cause death assessed through June 2002. Analyses are reported for 4 groups defined according to thyroid function test results: subclinical hyperthyroidism, euthyroidism, subclinical hypothyroidism, and overt hypothyroidism. RESULTS: Individuals with overt thyrotoxicosis (n = 4) were excluded because of small numbers. Eighty-two percent of participants (n = 2639) had normal thyroid function, 15% (n = 496) had subclinical hypothyroidism, 1.6% (n = 51) had overt hypothyroidism, and 1.5% (n = 47) had subclinical hyperthyroidism. After exclusion of those with prevalent atrial fibrillation, individuals with subclinical hyperthyroidism had a greater incidence of atrial fibrillation compared with those with normal thyroid function (67 events vs 31 events per 1000 person-years; adjusted hazard ratio, 1.98; 95% confidence interval, 1.29-3.03). No differences were seen between the subclinical hyperthyroidism group and euthyroidism group for incident coronary heart disease, cerebrovascular disease, cardiovascular death, or all-cause death. Likewise, there were no differences between the subclinical hypothyroidism or overt hypothyroidism groups and the euthyroidism group for cardiovascular outcomes or mortality. Specifically, individuals with subclinical hypothyroidism had an adjusted hazard ratio of 1.07 (95% confidence interval, 0.90-1.28) for incident coronary heart disease. CONCLUSION: Our data show an association between subclinical hyperthyroidism and development of atrial fibrillation but do not support the hypothesis that unrecognized subclinical hyperthyroidism or subclinical hypothyroidism is associated with other cardiovascular disorders or mortality.
Published:
February 28, 2006
Title:
Ecological and evolutionary forces shaping microbial diversity in the human intestine
Authors:
Ley, Ruth E.; Peterson, Daniel A.; Gordon, Jeffrey I.
Abstract:
The human gut is populated with as many as 100 trillion cells, whose collective genome, the microbiome, is a reflection of evolutionary selection pressures acting at the level of the host and at the level of the microbial cell. The ecological rules that govern the shape of microbial diversity in the gut apply to mutualists and pathogens alike.
Published:
February 23, 2006
Title:
A Prospective Study of Serum C-Reactive Protein and Colorectal Cancer Risk in Men
Authors:
Gunter, Marc J.; Stolzenberg-Solomon, Rachael; Cross, Amanda J.; Leitzmann, Michael F.; Weinstein, Stephanie; Wood, Richard J.; Virtamo, Jarmo; Taylor, Philip R.; Albanes, Demetrius; Sinha, Rashmi
Abstract:
Published:
February 14, 2006
Title:
Effects of Low-Carbohydrate vs Low-Fat Diets on Weight Loss and Cardiovascular Risk Factors: A Meta-analysis of Randomized Controlled Trials
Authors:
Nordmann, Alain J.; Nordmann, Abigail; Briel, Matthias; Keller, Ulrich; Yancy, William S.; Brehm, Bonnie J.; Bucher, Heiner C.
Abstract:
Background
Low-carbohydrate diets have become increasingly popular for weight loss. However, evidence from individual trials about benefits and risks of these diets to achieve weight loss and modify cardiovascular risk factors is preliminary.
Methods
We used the Cochrane Collaboration search strategy to identify trials comparing the effects of low-carbohydrate diets without restriction of energy intake vs low-fat diets in individuals with a body mass index (calculated as weight in kilograms divided by the square of height in meters) of at least 25. Included trials had to report changes in body weight in intention-to-treat analysis and to have a follow-up of at least 6 months. Two reviewers independently assessed trial eligibility and quality of randomized controlled trials.
Results
Five trials including a total of 447 individuals fulfilled our inclusion criteria. After 6 months, individuals assigned to low-carbohydrate diets had lost more weight than individuals randomized to low-fat diets (weighted mean difference, –3.3 kg; 95% confidence interval [CI], −5.3 to −1.4 kg). This difference was no longer obvious after 12 months (weighted mean difference, −1.0 kg; 95% CI, −3.5 to 1.5 kg). There were no differences in blood pressure. Triglyceride and high-density lipoprotein cholesterol values changed more favorably in individuals assigned to low-carbohydrate diets (after 6 months, for triglycerides, weighted mean difference, −22.1 mg/dL [−0.25 mmol/L]; 95% CI, −38.1 to −5.3 mg/dL [−0.43 to −0.06 mmol/L]; and for high-density lipoprotein cholesterol, weighted mean difference, 4.6 mg/dL [0.12 mmol/L]; 95% CI, 1.5-8.1 mg/dL [0.04-0.21 mmol/L]), but total cholesterol and low-density lipoprotein cholesterol values changed more favorably in individuals assigned to low-fat diets (weighted mean difference in low-density lipoprotein cholesterol after 6 months, 5.4 mg/dL [0.14 mmol/L]; 95% CI, 1.2-10.1 mg/dL [0.03-0.26 mmol/L]).
Conclusions
Low-carbohydrate, non–energy-restricted diets appear to be at least as effective as low-fat, energy-restricted diets in inducing weight loss for up to 1 year. However, potential favorable changes in triglyceride and high-density lipoprotein cholesterol values should be weighed against potential unfavorable changes in low-density lipoprotein cholesterol values when low-carbohydrate diets to induce weight loss are considered.
Published:
February 12, 2006
Title:
Low-Fat Dietary Pattern and Risk of Cardiovascular Disease: The Women's Health Initiative Randomized Controlled Dietary Modification Trial
Authors:
Howard, Barbara V.; Horn, Linda Van; Hsia, Judith; Manson, JoAnn E.; Stefanick, Marcia L.; Wassertheil-Smoller, Sylvia; Kuller, Lewis H.; LaCroix, Andrea Z.; Langer, Robert D.; Lasser, Norman L.; Lewis, Cora E.; Limacher, Marian C.; Margolis, Karen L.; Mysiw, W. Jerry; Ockene, Judith K.; Parker, Linda M.; Perri, Michael G.; Phillips, Lawrence; Prentice, Ross L.; Robbins, John; Rossouw, Jacques E.; Sarto, Gloria E.; Schatz, Irwin J.; Snetselaar, Linda G.; Stevens, Victor J.; Tinker, Lesley F.; Trevisan, Maurizio; Vitolins, Mara Z.; Anderson, Garnet L.; Assaf, Annlouise R.; Bassford, Tamsen; Beresford, Shirley A. A.; Black, Henry R.; Brunner, Robert L.; Brzyski, Robert G.; Caan, Bette; Chlebowski, Rowan T.; Gass, Margery; Granek, Iris; Greenland, Philip; Hays, Jennifer; Heber, David; Heiss, Gerardo; Hendrix, Susan L.; Hubbell, F. Allan; Johnson, Karen C.; Kotchen, Jane Morley
Abstract:
ContextMultiple epidemiologic studies and some trials have linked diet with cardiovascular disease (CVD) prevention, but long-term intervention data are needed.ObjectiveTo test the hypothesis that a dietary intervention, intended to be low in fat and high in vegetables, fruits, and grains to reduce cancer, would reduce CVD risk.Design, Setting, and ParticipantsRandomized controlled trial of 48 835 postmenopausal women aged 50 to 79 years, of diverse backgrounds and ethnicities, who participated in the Women's Health Initiative Dietary Modification Trial. Women were randomly assigned to an intervention (19 541 [40%]) or comparison group (29 294 [60%]) in a free-living setting. Study enrollment occurred between 1993 and 1998 in 40 US clinical centers; mean follow-up in this analysis was 8.1 years.InterventionIntensive behavior modification in group and individual sessions designed to reduce total fat intake to 20% of calories and increase intakes of vegetables/fruits to 5 servings/d and grains to at least 6 servings/d. The comparison group received diet-related education materials.Main Outcome MeasuresFatal and nonfatal coronary heart disease (CHD), fatal and nonfatal stroke, and CVD (composite of CHD and stroke).ResultsBy year 6, mean fat intake decreased by 8.2% of energy intake in the intervention vs the comparison group, with small decreases in saturated (2.9%), monounsaturated (3.3%), and polyunsaturated (1.5%) fat; increases occurred in intakes of vegetables/fruits (1.1 servings/d) and grains (0.5 serving/d). Low-density lipoprotein cholesterol levels, diastolic blood pressure, and factor VIIc levels were significantly reduced by 3.55 mg/dL, 0.31 mm Hg, and 4.29%, respectively; levels of high-density lipoprotein cholesterol, triglycerides, glucose, and insulin did not significantly differ in the intervention vs comparison groups. The numbers who developed CHD, stroke, and CVD (annualized incidence rates) were 1000 (0.63%), 434 (0.28%), and 1357 (0.86%) in the intervention and 1549 (0.65%), 642 (0.27%), and 2088 (0.88%) in the comparison group. The diet had no significant effects on incidence of CHD (hazard ratio [HR], 0.97; 95% confidence interval [CI], 0.90-1.06), stroke (HR, 1.02; 95% CI, 0.90-1.15), or CVD (HR, 0.98; 95% CI, 0.92-1.05). Excluding participants with baseline CVD (3.4%), the HRs (95% CIs) for CHD and stroke were 0.94 (0.86-1.02) and 1.02 (0.90-1.17), respectively. Trends toward greater reductions in CHD risk were observed in those with lower intakes of saturated fat or trans fat or higher intakes of vegetables/fruits.ConclusionsOver a mean of 8.1 years, a dietary intervention that reduced total fat intake and increased intakes of vegetables, fruits, and grains did not significantly reduce the risk of CHD, stroke, or CVD in postmenopausal women and achieved only modest effects on CVD risk factors, suggesting that more focused diet and lifestyle interventions may be needed to improve risk factors and reduce CVD risk.Clinical Trials RegistrationClinicalTrials.gov Identifier: NCT00000611
Published:
February 7, 2006
Title:
Low-fat dietary pattern and risk of colorectal cancer: the Women's Health Initiative Randomized Controlled Dietary Modification Trial
Authors:
Beresford, Shirley A. A.; Johnson, Karen C.; Ritenbaugh, Cheryl; Lasser, Norman L.; Snetselaar, Linda G.; Black, Henry R.; Anderson, Garnet L.; Assaf, Annlouise R.; Bassford, Tamsen; Bowen, Deborah; Brunner, Robert L.; Brzyski, Robert G.; Caan, Bette; Chlebowski, Rowan T.; Gass, Margery; Harrigan, Rosanne C.; Hays, Jennifer; Heber, David; Heiss, Gerardo; Hendrix, Susan L.; Howard, Barbara V.; Hsia, Judith; Hubbell, F. Allan; Jackson, Rebecca D.; Kotchen, Jane Morley; Kuller, Lewis H.; LaCroix, Andrea Z.; Lane, Dorothy S.; Langer, Robert D.; Lewis, Cora E.; Manson, JoAnn E.; Margolis, Karen L.; Mossavar-Rahmani, Yasmin; Ockene, Judith K.; Parker, Linda M.; Perri, Michael G.; Phillips, Lawrence; Prentice, Ross L.; Robbins, John; Rossouw, Jacques E.; Sarto, Gloria E.; Stefanick, Marcia L.; Van Horn, Linda; Vitolins, Mara Z.; Wactawski-Wende, Jean; Wallace, Robert B.; Whitlock, Evelyn
Abstract:
CONTEXT: Observational studies and polyp recurrence trials are not conclusive regarding the effects of a low-fat dietary pattern on risk of colorectal cancer, necessitating a primary prevention trial. OBJECTIVE: To evaluate the effects of a low-fat eating pattern on risk of colorectal cancer in postmenopausal women. DESIGN, SETTING, AND PARTICIPANTS: The Women's Health Initiative Dietary Modification Trial, a randomized controlled trial conducted in 48,835 postmenopausal women aged 50 to 79 years recruited between 1993 and 1998 from 40 clinical centers throughout the United States. INTERVENTIONS: Participants were randomly assigned to the dietary modification intervention (n = 19,541; 40%) or the comparison group (n = 29,294; 60%). The intensive behavioral modification program aimed to motivate and support reductions in dietary fat, to increase consumption of vegetables and fruits, and to increase grain servings by using group sessions, self-monitoring techniques, and other tailored and targeted strategies. Women in the comparison group continued their usual eating pattern. MAIN OUTCOME MEASURE: Invasive colorectal cancer incidence. RESULTS: A total of 480 incident cases of invasive colorectal cancer occurred during a mean follow-up of 8.1 (SD, 1.7) years. Intervention group participants significantly reduced their percentage of energy from fat by 10.7% more than did the comparison group at 1 year, and this difference between groups was mostly maintained (8.1% at year 6). Statistically significant increases in vegetable, fruit, and grain servings were also made. Despite these dietary changes, there was no evidence that the intervention reduced the risk of invasive colorectal cancer during the follow-up period. There were 201 women with invasive colorectal cancer (0.13% per year) in the intervention group and 279 (0.12% per year) in the comparison group (hazard ratio, 1.08; 95% confidence interval, 0.90-1.29). Secondary analyses suggested potential interactions with baseline aspirin use and combined estrogen-progestin use status (P = .01 for each). Colorectal examination rates, although not protocol defined, were comparable between the intervention and comparison groups. Similar results were seen in analyses adjusting for adherence to the intervention. CONCLUSION: In this study, a low-fat dietary pattern intervention did not reduce the risk of colorectal cancer in postmenopausal women during 8.1 years of follow-up. CLINICAL TRIALS REGISTRATION: ClinicalTrials.gov Identifier: NCT00000611.
Published:
February 7, 2006
Title:
Low-fat dietary pattern and risk of invasive breast cancer: the Women's Health Initiative Randomized Controlled Dietary Modification Trial
Authors:
Prentice, Ross L.; Caan, Bette; Chlebowski, Rowan T.; Patterson, Ruth; Kuller, Lewis H.; Ockene, Judith K.; Margolis, Karen L.; Limacher, Marian C.; Manson, JoAnn E.; Parker, Linda M.; Paskett, Electra; Phillips, Lawrence; Robbins, John; Rossouw, Jacques E.; Sarto, Gloria E.; Shikany, James M.; Stefanick, Marcia L.; Thomson, Cynthia A.; Van Horn, Linda; Vitolins, Mara Z.; Wactawski-Wende, Jean; Wallace, Robert B.; Wassertheil-Smoller, Sylvia; Whitlock, Evelyn; Yano, Katsuhiko; Adams-Campbell, Lucile; Anderson, Garnet L.; Assaf, Annlouise R.; Beresford, Shirley A. A.; Black, Henry R.; Brunner, Robert L.; Brzyski, Robert G.; Ford, Leslie; Gass, Margery; Hays, Jennifer; Heber, David; Heiss, Gerardo; Hendrix, Susan L.; Hsia, Judith; Hubbell, F. Allan; Jackson, Rebecca D.; Johnson, Karen C.; Kotchen, Jane Morley; LaCroix, Andrea Z.; Lane, Dorothy S.; Langer, Robert D.; Lasser, Norman L.; Henderson, Maureen M.
Abstract:
CONTEXT: The hypothesis that a low-fat dietary pattern can reduce breast cancer risk has existed for decades but has never been tested in a controlled intervention trial. OBJECTIVE: To assess the effects of undertaking a low-fat dietary pattern on breast cancer incidence. DESIGN AND SETTING: A randomized, controlled, primary prevention trial conducted at 40 US clinical centers from 1993 to 2005. PARTICIPANTS: A total of 48,835 postmenopausal women, aged 50 to 79 years, without prior breast cancer, including 18.6% of minority race/ethnicity, were enrolled. INTERVENTIONS: Women were randomly assigned to the dietary modification intervention group (40% [n = 19,541]) or the comparison group (60% [n = 29,294]). The intervention was designed to promote dietary change with the goals of reducing intake of total fat to 20% of energy and increasing consumption of vegetables and fruit to at least 5 servings daily and grains to at least 6 servings daily. Comparison group participants were not asked to make dietary changes. MAIN OUTCOME MEASURE: Invasive breast cancer incidence. RESULTS: Dietary fat intake was significantly lower in the dietary modification intervention group compared with the comparison group. The difference between groups in change from baseline for percentage of energy from fat varied from 10.7% at year 1 to 8.1% at year 6. Vegetable and fruit consumption was higher in the intervention group by at least 1 serving per day and a smaller, more transient difference was found for grain consumption. The number of women who developed invasive breast cancer (annualized incidence rate) over the 8.1-year average follow-up period was 655 (0.42%) in the intervention group and 1072 (0.45%) in the comparison group (hazard ratio, 0.91; 95% confidence interval, 0.83-1.01 for the comparison between the 2 groups). Secondary analyses suggest a lower hazard ratio among adherent women, provide greater evidence of risk reduction among women having a high-fat diet at baseline, and suggest a dietary effect that varies by hormone receptor characteristics of the tumor. CONCLUSIONS: Among postmenopausal women, a low-fat dietary pattern did not result in a statistically significant reduction in invasive breast cancer risk over an 8.1-year average follow-up period. However, the nonsignificant trends observed suggesting reduced risk associated with a low-fat dietary pattern indicate that longer, planned, nonintervention follow-up may yield a more definitive comparison. CLINICAL TRIALS REGISTRATION: ClinicalTrials.gov Identifier: NCT00000611.
Published:
February 7, 2006
Title:
Carbohydrate Restriction Alters Lipoprotein Metabolism by Modifying VLDL, LDL, and HDL Subfraction Distribution and Size in Overweight Men
Authors:
Wood, Richard J.; Volek, Jeff S.; Liu, Yanzhu; Shachter, Neil S.; Contois, John H.; Fernandez, Maria Luz
Abstract:
Abstract. To determine the effects of carbohydrate restriction (CR) with and without soluble fiber on lipoprotein metabolism, 29 men participated in a 12-wk we
Published:
January 31, 2006
Title:
Effects of long-term vegetarian diets on cardiovascular autonomic functions in healthy postmenopausal women
Authors:
Fu, Chin-Hua; Yang, Cheryl C. H.; Lin, Chin-Lon; Kuo, Terry B. J.
Abstract:
The incidence of cardiovascular disease is higher in postmenopausal women than in premenopausal women. We hypothesized that long-term vegetarian diets might modulate cardiovascular autonomic functions measured by frequency-domain techniques in healthy postmenopausal women. A total of 35 healthy vegetarians (mean age +/- SEM 55.0 +/- 1.3 years) who had been vegetarians for > or =2 years and 35 omnivores (55.1 +/- 1.4 years) participated in this study. These subjects were all postmenopausal without hormone replacement therapy. Fluctuations in arterial blood pressure and heart rate variability were diffracted into low-frequency (0.04 to 0.15 Hz) and high-frequency (0.15 to 0.4 Hz) segments. Cardiovascular autonomic functions and baroreflex sensitivity were evaluated by specific frequency-domain measures. The vegetarians had statistically lower systolic and diastolic blood pressure, and lower serum total cholesterol, low-density lipoprotein cholesterol, triglycerides, fasting blood sugar, and hemoglobin levels compared with the nonvegetarians. They also exhibited a significantly higher high-frequency power of heart rate variability and increased baroreflex sensitivity than did omnivores. No statistical differences were found in the low-frequency/high-frequency ratio or percentage of low frequency of heart rate variability between the 2 groups. In conclusion, in addition to the lower blood pressure and lipid concentrations in vegetarians, long-term vegetarian diets may facilitate vagal regulation of the heart and increase baroreflex sensitivity in healthy postmenopausal women, without increasing the sympathetic modulations of the cardiovascular system.
Published:
January 31, 2006
Title:
Effects of variation in protein and carbohydrate intake on body mass and composition during energy restriction: a meta-regression
Authors:
Krieger, James W.; Sitren, Harry S.; Daniels, Michael J.; Langkamp-Henken, Bobbi
Abstract:
ABSTRACT. Background: It is unclear whether low-carbohydrate, high-protein, weight-loss diets benefit body mass and composition beyond energy restriction alone
Published:
January 31, 2006
Title:
Epidemiology of gastric cancer
Authors:
Crew, Katherine D.; Neugut, Alfred I.
Abstract:
The incidence and mortality of gastric cancer have fallen dramatically in US and elsewhere over the past several decades. Nonetheless, gastric cancer remains a major public health issue as the fourth most common cancer and the second leading cause of cancer death worldwide. Demographic trends differ by tumor location and histology. While there has been a marked decline in distal, intestinal type gastric cancers, the incidence of proximal, diffuse type adenocarcinomas of the gastric cardia has been increasing, particularly in the Western countries. Incidence by tumor sub-site also varies widely based on geographic location, race, and socio-economic status. Distal gastric cancer predominates in developing countries, among blacks, and in lower socio-economic groups, whereas proximal tumors are more common in developed countries, among whites, and in higher socio-economic classes. Diverging trends in the incidence of gastric cancer by tumor location suggest that they may represent two diseases with different etiologies. The main risk factors for distal gastric cancer include Helicobacter pylori (H pylori) infection and dietary factors, whereas gastroesophageal reflux disease and obesity play important roles in the development of proximal stomach cancer. The purpose of this review is to examine the epidemiology and risk factors of gastric cancer, and to discuss strategies for primary prevention.
Published:
January 20, 2006
Title:
Case report of 5 siblings: malnutrition? Rickets? DiGeorge syndrome? Developmental delay?
Authors:
Cundiff, David K.; Harris, William
Abstract:
BACKGROUND: Parents of six children are facing a trial on charges of aggravated manslaughter in the care a 5 1/2 month old infant who died suddenly and neglect of their four older children for causing them to be malnourished by feeding them all an exclusively raw foods vegan diet. Both parents declined plea bargains and plan to defend themselves in court. CASE PRESENTATION: The fifth child born to a married couple was breast-fed until 2 1/2 months. Subsequently, the parents fed the baby an exclusively raw foods diet prepared in a blender at home. The four older children, ages 18 months-6 1/2 years also ate an exclusively raw foods vegan diet. None of the four older children had significant previous injuries or serious illnesses. At autopsy, the infant weighed 3180 mg (6.99 pounds) and appeared emaciated. The thymus gland was absent and parathyroid glands were not located. The lungs were "congested." DiGeorge anomaly cannot be ruled out from these findings. Although, the coroner ruled that "malnutrition" was the sole cause of death, malnutrition, according to the World Health Organization definition, cannot be diagnosed in this infant. Compared with standard growth charts, the older children fell 2.1-4.1 standard deviations below the mean for North American children in height and weight. Labs were normal except for a low cholesterol level in all and a low prealbumin in one of three children tested. Therefore, malnutrition cannot be diagnosed in these children. The pediatrician diagnosed rickets in the four-year-old. However, chest x-rays were normal in all and long bone x-rays showed minimal changes in one child--no sign of rickets. The clinical diagnosis of rickets was not confirmed by the Center for Disease Control's criteria. A psychologist diagnosed the 18-month-old as developmentally delayed to the level of a 15-month-old, but this diagnosis is questionable. CONCLUSION: The raw foods vegan diet and possibly inherited small stature from the father's side account for their relatively low heights and weights. Catch-up growth will probably occur on the standard American diet but would have also been expected if they had remained on a vegan diet.
Published:
January 15, 2006
Title:
Comparison of isocaloric very low carbohydrate/high saturated fat and high carbohydrate/low saturated fat diets on body composition and cardiovascular risk
Authors:
Noakes, Manny; Foster, Paul R.; Keogh, Jennifer B.; James, Anthony P.; Mamo, John C.; Clifton, Peter M.
Abstract:
It is speculated that high saturated fat very low carbohydrate diets (VLCARB) have adverse effects on cardiovascular risk but evidence for this in controlled studies is lacking. The objective of this study was to compare, under isocaloric conditions, the effects of a VLCARB to 2 low saturated fat high carbohydrate diets on body composition and cardiovascular risk.
Published:
January 10, 2006
Title:
Low-fat dietary pattern and weight change over 7 years: the Women's Health Initiative Dietary Modification Trial
Authors:
Howard, Barbara V.; Manson, JoAnn E.; Stefanick, Marcia L.; Beresford, Shirley A.; Frank, Gail; Jones, Bobette; Rodabough, Rebecca J.; Snetselaar, Linda; Thomson, Cynthia; Tinker, Lesley; Vitolins, Mara; Prentice, Ross
Abstract:
CONTEXT: Obesity in the United States has increased dramatically during the past several decades. There is debate about optimum calorie balance for prevention of weight gain, and proponents of some low-carbohydrate diet regimens have suggested that the increasing obesity may be attributed, in part, to low-fat, high-carbohydrate diets. OBJECTIVES: To report data on body weight in a long-term, low-fat diet trial for which the primary end points were breast and colorectal cancer and to examine the relationships between weight changes and changes in dietary components. DESIGN, SETTING, AND PARTICIPANTS: Randomized intervention trial of 48,835 postmenopausal women in the United States who were of diverse backgrounds and ethnicities and participated in the Women's Health Initiative Dietary Modification Trial; 40% (19,541) were randomized to the intervention and 60% (29,294) to a control group. Study enrollment was between 1993 and 1998, and this analysis includes a mean follow-up of 7.5 years (through August 31, 2004). INTERVENTIONS: The intervention included group and individual sessions to promote a decrease in fat intake and increases in vegetable, fruit, and grain consumption and did not include weight loss or caloric restriction goals. The control group received diet-related education materials. MAIN OUTCOME MEASURE: Change in body weight from baseline to follow-up. RESULTS: Women in the intervention group lost weight in the first year (mean of 2.2 kg, P<.001) and maintained lower weight than control women during an average 7.5 years of follow-up (difference, 1.9 kg, P
Published:
January 3, 2006
Title:
Health care discrimination, processes of care, and diabetes patients’ health status
Authors:
Piette, John D.; Bibbins-Domingo, Kirsten; Schillinger, Dean
Abstract:
Objective We examined whether diabetes patients report discrimination when seeking health care, whether problems with interpersonal processes of care (IPC) were associated with discrimination reports, and the linkage between discrimination and patients’ health. Methods 810 diabetes patients were surveyed. Surveys were linked to hemoglobin A1c (A1C) and total cholesterol test results. Results 14% of participants reported experiencing discrimination in health care during the prior year, including discrimination due to their race (8%), education or income (9%), age (7%), and gender (10% of women). Patients with poorer than average ratings of their IPC had 2–8 times greater risk of reporting health care discrimination. Patients reporting health care discrimination had A1C levels that were higher than other patients (P=0.002), more symptoms (P
Published:
December 31, 2005
Title:
Short-term effects of severe dietary carbohydrate-restriction advice in Type 2 diabetes—a randomized controlled trial
Authors:
Daly, M. E.; Paisey, R.; Paisey, R.; Millward, B. A.; Eccles, C.; Williams, K.; Hammersley, S.; MacLeod, K. M.; Gale, T. J.
Abstract:
Abstract Objective? This study sought to examine the effects of a 3-month programme of dietary advice to restrict carbohydrate intake compared with reduced-portion, low-fat advice in obese subjects with poorly controlled Type 2 diabetes. Research design and methods? One hundred and two patients with Type 2 diabetes were recruited across three centres and randomly allocated to receive group education and individual dietary advice. Weight, glycaemic control, lipids and blood pressure were assessed at baseline and 3 months. Dietary quality was assessed at the end of study. Results? Weight loss was greater in the low-carbohydrate (LC) group (?3.55 ± 0.63, mean ± sem) vs. ?0.92 ± 0.40 kg, P = 0.001) and cholesterol : high-density lipoprotein (HDL) ratio improved (?0.48 ± 0.11 vs. ?0.10 ± 0.10, P = 0.01). However, relative saturated fat intake was greater (13.9 ± 0.71 vs. 11.0 ± 0.47% of dietary intake, P
Published:
December 31, 2005
Title:
2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) level in human hair as biomarkers for dietary grilled/stir-fried meat and fish intake
Authors:
Kobayashi, Minatsu; Hanaoka, Tomoyuki; Hashimoto, Hiroko; Tsugane, Shoichiro
Abstract:
Several case-control studies have reported possible associations between heterocyclic amine (HCA) intake and the risk of cancer. However, the validity of a questionnaire to assess HCA intake has hardly been examined. In particular, no biomarker which could serve as an independent measure of habitual HCA intake has been established. Therefore, the validity of a questionnaire to assess HCA intake by means of a biomarker remains to be investigated. In this study, we examined the availability of hair HCAs as a biochemical indicator of dietary intake of HCAs. Study subjects were 20 volunteers (7 men and 13 women) aged 25-57 years, either residents of Tokyo or the neighboring cities in Japan. We collected individual weighed dietary records (DR) over 28 consecutive days. Approximately 3-5 g of hair was collected twice from all subjects before and after DR at intervals of 1-3 months. The mean (S.D.) 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) level of hair was 1376.0 pg/g hair (928.9) and 16.6 ng/g melanin (12.3). A steady increase in the mean PhIP level in hair from the lowest to the highest tertile of the grilled/stir-fried meat intake was observed (P = 0.009), but not in the grilled/stir-fried fish intake (P = 0.461). The PhIP level in hair was highly correlated with the grilled/stir-fried meat intake (r = 0.68) but not with the grilled/stir-fried fish intake (r = 0.28). These observations were made of hair with and without melanin adjustment. The present study indicates that the PhIP level in hair can be used as a biological indicator of dietary intake of HCAs.
Published:
December 29, 2005
Title:
The effects of a low-carbohydrate, ketogenic diet on the polycystic ovary syndrome: a pilot study
Authors:
Mavropoulos, John C.; Yancy, William S.; Hepburn, Juanita; Westman, Eric C.
Abstract:
BACKGROUND: Polycystic ovary syndrome (PCOS) is the most common endocrine disorder affecting women of reproductive age and is associated with obesity, hyperinsulinemia, and insulin resistance. Because low carbohydrate diets have been shown to reduce insulin resistance, this pilot study investigated the six-month metabolic and endocrine effects of a low-carbohydrate, ketogenic diet (LCKD) on overweight and obese women with PCOS. RESULTS: Eleven women with a body mass index >27 kg/m2 and a clinical diagnosis of PCOS were recruited from the community. They were instructed to limit their carbohydrate intake to 20 grams or less per day for 24 weeks. Participants returned every two weeks to an outpatient research clinic for measurements and reinforcement of dietary instruction. In the 5 women who completed the study, there were significant reductions from baseline to 24 weeks in body weight (-12%), percent free testosterone (-22%), LH/FSH ratio (-36%), and fasting insulin (-54%). There were non-significant decreases in insulin, glucose, testosterone, HgbA1c, triglyceride, and perceived body hair. Two women became pregnant despite previous infertility problems. CONCLUSION: In this pilot study, a LCKD led to significant improvement in weight, percent free testosterone, LH/FSH ratio, and fasting insulin in women with obesity and PCOS over a 24 week period.
Published:
December 15, 2005
Title:
A low-carbohydrate, ketogenic diet to treat type 2 diabetes
Authors:
Yancy, William S.; Foy, Marjorie; Chalecki, Allison M.; Vernon, Mary C.; Westman, Eric C.
Abstract:
The low-carbohydrate, ketogenic diet (LCKD) may be effective for improving glycemia and reducing medications in patients with type 2 diabetes.
Published:
November 30, 2005
Title:
Carbohydrate restriction improves the features of Metabolic Syndrome. Metabolic Syndrome may be defined by the response to carbohydrate restriction
Authors:
Volek, Jeff S.; Feinman, Richard D.
Abstract:
Metabolic Syndrome (MetS) represents a constellation of markers that indicates a predisposition to diabetes, cardiovascular disease and other pathologic states. The definition and treatment are a matter of current debate and there is not general agreement on a precise definition or, to some extent, whether the designation provides more information than the individual components. We consider here five indicators that are central to most definitions and we provide evidence from the literature that these are precisely the symptoms that respond to reduction in dietary carbohydrate (CHO). Carbohydrate restriction is one of several strategies for reducing body mass but even in the absence of weight loss or in comparison with low fat alternatives, CHO restriction is effective at ameliorating high fasting glucose and insulin, high plasma triglycerides (TAG), low HDL and high blood pressure. In addition, low fat, high CHO diets have long been known to raise TAG, lower HDL and, in the absence of weight loss, may worsen glycemic control. Thus, whereas there are numerous strategies for weight loss, a patient with high BMI and high TAG is likely to benefit most from a regimen that reduces CHO intake. Reviewing the literature, benefits of CHO restriction are seen in normal or overweight individuals, in normal patients who meet the criteria for MetS or in patients with frank diabetes. Moreover, in low fat studies that ameliorate LDL and total cholesterol, controls may do better on the symptoms of MetS. On this basis, we feel that MetS is a meaningful, useful phenomenon and may, in fact, be operationally defined as the set of markers that responds to CHO restriction. Insofar as this is an accurate characterization it is likely the result of the effect of dietary CHO on insulin metabolism. Glucose is the major insulin secretagogue and insulin resistance has been tied to the hyperinsulinemic state or the effect of such a state on lipid metabolism. The conclusion is probably not surprising but has not been explicitly stated before. The known effects of CHO-induced hypertriglyceridemia, the HDL-lowering effect of low fat, high CHO interventions and the obvious improvement in glucose and insulin from CHO restriction should have made this evident. In addition, recent studies suggest that a subset of MetS, the ratio of TAG/HDL, is a good marker for insulin resistance and risk of CVD, and this indicator is reliably reduced by CHO restriction and exacerbated by high CHO intake. Inability to make this connection in the past has probably been due to the fact that individual responses have been studied in isolation as well as to the emphasis of traditional therapeutic approaches on low fat rather than low CHO. We emphasize that MetS is not a disease but a collection of markers. Individual physicians must decide whether high LDL, or other risk factors are more important than the features of MetS in any individual case but if MetS is to be considered it should be recognized that reducing CHO will bring improvement. Response of symptoms to CHO restriction might thus provide a new experimental criterion for MetS in the face of on-going controversy about a useful definition. As a guide to future research, the idea that control of insulin metabolism by CHO intake is, to a first approximation, the underlying mechanism in MetS is a testable hypothesis.
Published:
November 15, 2005
Title:
Decorin and biglycan expression is differentially altered in several muscular dystrophies
Authors:
Zanotti, Simona; Negri, Tiziana; Cappelletti, Cristina; Bernasconi, Pia; Canioni, Eleonora; Di Blasi, Claudia; Pegoraro, Elena; Angelini, Corrado; Ciscato, Patrizia; Prelle, Alessandro; Mantegazza, Renato; Morandi, Lucia; Mora, Marina
Abstract:
Published:
October 31, 2005
Title:
Diet, vegetarian food and prostate carcinoma among men in Taiwan
Authors:
Chen, Y. C.; Chiang, C. I.; Lin, R. S.; Pu, Y. S.; Lai, M. K.; Sung, F.-C.
Abstract:
In a case-control study in a veterans hospital in Taiwan, we compared 237 histology-confirmed prostate carcinoma cases with 481 controls, frequency matched by age, for their consumption of vegetarian food, namely soybean products, rice, wheat protein and other vegetables. The multivariable logistic regression analysis showed a significant association with such food (odds ratio (OR)=0.67, 95% confidence interval (CI)=0.47, 0.94). This beneficial effect presented for men with body mass index (BMI) < or =25 kg m(-2) (OR=0.50, 95% CI=0.32, 0.76) but not for men with greater BMI. The OR of prostate carcinoma for men with BMI 25 kg m(-2)). Other significant risk factors associated with the disease included higher income (OR=2.40, 95% CI=1.07, 5.42), physical activity (OR=1.75, 95% CI=1.08, 2.83), being married (OR=2.49, 95% CI=1.40, 4.43) and coffee consumption (OR=1.88, 95% CI=1.07, 3.30). Stratified analysis also showed that the consumption of fish/shellfish had an adverse association for men with higher BMI. This study suggests that the intake of the low fat local vegetarian food has a protective effect against prostate carcinoma for thin men in this study population.
Published:
October 30, 2005
Title:
Targeting energy metabolism in brain cancer: review and hypothesis
Authors:
Seyfried, Thomas N.; Mukherjee, Purna
Abstract:
Malignant brain tumors are a significant health problem in children and adults and are often unmanageable. As a metabolic disorder involving the dysregulation of glycolysis and respiration, malignant brain cancer is potentially manageable through changes in metabolic environment. A radically different approach to brain cancer management is proposed that combines metabolic control analysis with the evolutionarily conserved capacity of normal cells to survive extreme shifts in physiological environment. In contrast to malignant brain tumors that are largely dependent on glycolysis for energy, normal neurons and glia readily transition to ketone bodies (beta-hydroxybutyrate) for energy in vivo when glucose levels are reduced. The bioenergetic transition from glucose to ketone bodies metabolically targets brain tumors through integrated anti-inflammatory, anti-angiogenic, and pro-apoptotic mechanisms. The approach focuses more on the genomic flexibility of normal cells than on the genomic defects of tumor cells and is supported from recent studies in orthotopic mouse brain tumor models and in human pediatric astrocytoma treated with dietary energy restriction and the ketogenic diet.
Published:
October 20, 2005
Title:
Early Mortality Among Medicare Beneficiaries Undergoing Bariatric Surgical Procedures
Authors:
Flum, David R.; Salem, Leon; Elrod, Jo Ann Broeckel; Dellinger, E. Patchen; Cheadle, Allen; Chan, Leighton
Abstract:
ContextCase series demonstrate that bariatric surgery can be performed with a low rate of perioperative mortality (0.5%), but the rate among high-risk patients and the community at large is unknown.ObjectivesTo evaluate the risk of early mortality among Medicare beneficiaries and to determine the relative risk of death among older patients.DesignRetrospective cohort study.Setting and PatientsAll fee-for-service Medicare beneficiaries, 1997-2002.Main Outcome MeasuresThirty-day, 90-day, and 1-year postsurgical all-cause mortality among patients undergoing bariatric procedures.ResultsA total of 16 155 patients underwent bariatric procedures (mean age, 47.7 years [SD, 11.3 years]; 75.8% women). The rates of 30-day, 90-day, and 1-year mortality were 2.0%, 2.8%, and 4.6%, respectively. Men had higher rates of early death than women (3.7% vs 1.5%, 4.8% vs 2.1%, and 7.5% vs 3.7% at 30 days, 90 days, and 1 year, respectively; P<.001). Mortality rates were greater for those aged 65 years or older compared with younger patients (4.8% vs 1.7% at 30 days, 6.9% vs 2.3% at 90 days, and 11.1% vs 3.9% at 1 year; P<.001). After adjustment for sex and comorbidity index, the odds of death within 90 days were 5-fold greater for older Medicare beneficiaries (aged ≥75 years; n = 136) than for those aged 65 to 74 years (n = 1381; odds ratio, 5.0; 95% confidence interval, 3.1-8.0). The odds of death at 90 days were 1.6 times higher (95% confidence interval, 1.3-2.0) for patients of surgeons with less than the median surgical volume of bariatric procedures (among Medicare beneficiaries during the study period) after adjusting for age, sex, and comorbidity index.ConclusionsAmong Medicare beneficiaries, the risk of early death after bariatric surgery is considerably higher than previously suggested and associated with advancing age, male sex, and lower surgeon volume of bariatric procedures. Patients aged 65 years or older had a substantially higher risk of death within the early postoperative period than younger patients.
Published:
October 18, 2005
Title:
Filling the Gaps in Bariatric Surgical Research
Authors:
Courcoulas, Anita P.; Flum, David R.
Abstract:
Despite phenomenal growth in the use of bariatric surgical procedures, research on these interventions continues to be reported primarily through the case series of experienced practitioners1 and has focused only on selected outcomes. As a result, there is a gap between the proliferation of...
Published:
October 18, 2005
Title:
A ketogenic diet reduces amyloid beta 40 and 42 in a mouse model of Alzheimer's disease
Authors:
Van der Auwera, Ingrid; Wera, Stefaan; Van Leuven, Fred; Henderson, Samuel T.
Abstract:
BACKGROUND: Alzheimer's disease (AD) is a progressive neurodegenerative disorder that primarily strikes the elderly. Studies in both humans and animal models have linked the consumption of cholesterol and saturated fats with amyloid-beta (Abeta) deposition and development of AD. Yet, these studies did not examine high fat diets in combination with reduced carbohydrate intake. Here we tested the effect of a high saturated fat/low carbohydrate diet on a transgenic mouse model of AD. RESULTS: Starting at three months of age, two groups of female transgenic mice carrying the "London" APP mutation (APP/V717I) were fed either, a standard diet (SD) composed of high carbohydrate/low fat chow, or a ketogenic diet (KD) composed of very low carbohydrate/high saturated fat chow for 43 days. Animals fed the KD exhibited greatly elevated serum ketone body levels, as measured by beta-hydroxybutyrate (3.85 +/- 2.6 mM), compared to SD fed animals (0.29 +/- 0.06 mM). In addition, animals fed the KD lost body weight (SD 22.2 +/- 0.6 g vs. KD 17.5 +/- 1.4 g, p = 0.0067). In contrast to earlier studies, the brief KD feeding regime significantly reduced total brain Abeta levels by approximately 25%. Despite changes in ketone levels, body weight, and Abeta levels, the KD diet did not alter behavioral measures. CONCLUSION: Previous studies have suggested that diets rich in cholesterol and saturated fats increased the deposition of Abeta and the risk of developing AD. Here we demonstrate that a diet rich in saturated fats and low in carbohydrates can actually reduce levels of Abeta. Therefore, dietary strategies aimed at reducing Abeta levels should take into account interactions of dietary components and the metabolic outcomes, in particular, levels of carbohydrates, total calories, and presence of ketone bodies should be considered.
Published:
October 16, 2005
Title:
Glycation, ageing and carnosine: Are carnivorous diets beneficial?
Authors:
Hipkiss, Alan R.
Abstract:
Non-enzymic protein glycosylation (glycation) plays important roles in ageing and in diabetes and its secondary complications. Dietary constituents may play important roles in accelerating or suppressing glycation. It is suggested that carnivorous diets contain a potential anti-glycating agent, carnosine (β-alanyl-histidine), whilst vegetarians may lack intake of the dipeptide. The possible beneficial effects of carnosine and related structures on protein carbonyl stress, AGE formation, secondary diabetic complications and age-related neuropathology are discussed.
Published:
September 30, 2005
Title:
The role of work-related and personal factors in diabetes self-management
Authors:
Weijman, Iris; Ros, Wynand J. G.; Rutten, Guy E. H. M.; Schaufeli, Wilmar B.; Schabracq, Marc J.; Winnubst, Jacques A. M.
Abstract:
The aim of this study was to investigate how factors in the workplace and personal factors are related to the frequency with which people with diabetes perform self-management activities and the degree to which they do or do not experience the performing of self-management activities as a burden. Two hundred and ninety-two employees with insulin-treated diabetes completed questionnaires on socio-demographic and illness-related background variables, work experience, diabetes self-efficacy, social support outside of work, coping styles and self-management activities. The results indicate that employees who reported a high workload were more likely to perceive injecting insulin as a burden. The level of social support was positively related to the frequency of dietary self-management in type 2 diabetes and negatively related to the sense of being burdened by dietary self-management in type 1 diabetes. With respect to personal factors, we found that a diabetes avoidance coping style was associated particularly with infrequent blood glucose monitoring and a high sense of being burdened by blood glucose monitoring. Individuals with a low level of self-efficacy were more likely to perceive all types of self-management activities as a burden. These results may guide health professionals when counseling individuals with diabetes.
Published:
September 30, 2005
Title:
Dietary protein intake and renal function
Authors:
Martin, William F.; Armstrong, Lawrence E.; Rodriguez, Nancy R.
Abstract:
Recent trends in weight loss diets have led to a substantial increase in protein intake by individuals. As a result, the safety of habitually consuming dietary protein in excess of recommended intakes has been questioned. In particular, there is concern that high protein intake may promote renal damage by chronically increasing glomerular pressure and hyperfiltration. There is, however, a serious question as to whether there is significant evidence to support this relationship in healthy individuals. In fact, some studies suggest that hyperfiltration, the purported mechanism for renal damage, is a normal adaptative mechanism that occurs in response to several physiological conditions. This paper reviews the available evidence that increased dietary protein intake is a health concern in terms of the potential to initiate or promote renal disease. While protein restriction may be appropriate for treatment of existing kidney disease, we find no significant evidence for a detrimental effect of high protein intakes on kidney function in healthy persons after centuries of a high protein Western diet.
Published:
September 19, 2005
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