Published Science

The word fiber conjures up wholesome, earthy-crunchy images of squeaky clean intestines and free-flowing coronary arteries. Yet fiber is not a nutrient at all. What is fiber? Is it really healthy for us, and do we even need it? The word fiber conjures up wholesome, earthy-crunchy images of squeaky clean intestines and free-flowing coronary arteries. Yet fiber is not a nutrient at all, and is not absorbed by our bodies. What is fiber? What is the difference between soluble and insoluble fiber, is it really healthy for us, and do we even need to eat it? What is fiber? Fiber comes from the cell walls of plants. It provides shape and architectural support to the plant. Animals do not contain any fiber; we use bone and cartilage to support our bodies instead. Fiber is by definition indigestible by humans. There are two types of fiber: soluble and insoluble. All plant foods (fruits, vegetables, nuts, beans, seeds and grains) contain a combination of soluble and insoluble fiber in varying amounts. We are told that soluble fiber is good for us because it slows things down and we are told that insoluble fiber is good for us because it speeds things up. Hmmm . . . Insoluble fiber: the tough stuff insoluble fiber in intestineInsoluble fiber is affectionately called “roughage.” Insoluble fiber is called insoluble because it does not dissolve in water. It is the stuff that gives tree bark, nutshells and twigs their woody texture. Foods high in insoluble fiber include grains, seeds, nuts, vegetables and certain fruits. Insoluble fibers pass through our digestive system practically untouched, because even bacteria can’t easily digest them. We are told that insoluble fiber is good for us because it adds weighty “bulk” to the contents of our intestines, helping to push things along. Why expose the smooth inner surfaces of our intestines to these abrasive indigestibles? We are told that we need them to sweep our innards clean of potential toxins. Oddly enough, I was unable to locate a single scientific article explaining what these toxins are and how insoluble fiber removes them . . . therefore this must simply be a common belief—an appealing image that makes sense in our minds, but that has absolutely no science behind it. Soluble Fiber: the swell gel soluble fiber in intestineThe biggest difference between soluble fiber and insoluble fiber is that it is, as the name implies, soluble in water—it can partially dissolve in water. Most over-the-counter laxatives are made with soluble fiber. Soluble fiber dissolves partially in water, forming a gel—you can see this happen when you stir a soluble fiber supplement such as Metamucil® into a glass of water. The ability of soluble fiber to hold water is what allows fruits and soft vegetable parts to contain water and yet maintain their firm shape. The soluble fiber family includes a wide variety of plant compounds such as arabinoxylan, dextrins, inulin, waxes, chitins, pectins, and beta-glucan. Soluble fiber is found in apples and pears, oats, pitted fruits, psyllium, citrus fruits, beans, berries, and brussels sprouts, among other foods. Some types of soluble fiber are more “viscous” than others, meaning they form firmer, stickier gels. We are told that this swollen gel action is good for us for three reasons: Viscous soluble fiber binds some of the LDL or so-called “bad cholesterol” we eat so that less of it enters our bloodstream. Gels move more slowly through the intestine than liquids. When we eat something sweet along with soluble fiber, the gel will slow down the absorption of sugar into the bloodstream, which may reduce blood sugar spiking. The swollen gel helps us to feel full, so we may eat less food. These are all good things, right? Don’t we want to feel full, and lower our cholesterol and blood sugar levels? Yes, of course we do! So let’s take a look at each of these claims. Does fiber lower cholesterol levels? Yes. A recent review of studies on the effect of plant-based diets on cholesterol levels showed a maximum reduction in LDL cholesterol of about one-third [Mente 2009]. This is why fiber is advertised as “heart healthy.” Of course, if you’ve read the cholesterol page you know that a) LDL is not necessarily bad, and b) the most powerful way to improve your cholesterol profile is to eat a low-glycemic-index or low-carbohydrate diet. Can fiber lower blood sugar? Yes. Soluble fiber has been definitively shown to reduce the glycemic index (the degree to which your blood sugar will spike) of sweet or starchy foods, but only by 10 to 20% [Melanson 2006]. This is probably because fiber slows digestion of carbohydrates by interfering with normal digestion. Of course, a much more powerful and direct way to reduce the glycemic index of the foods you eat is to . . . avoid high-glycemic-index foods. Do high-fiber diets help with weight loss? No. Most studies show little to no weight loss benefit, but study results were mixed and many studies were poorly designed. According to Nutrition Reviews: “the limited number of clinical trials comparing high-fiber foods with low-fiber foods have not provided consistent data indicating that these diets are more efficacious for weight loss than low-fiber control diets.” An interesting analysis of twenty different studies of the use of guar gum (a soluble fiber supplement) in weight loss noted that the guar gum caused abdominal pain, flatulence, diarrhea and cramps, and concluded that: “guar gum is not efficacious for reducing body weight. Considering the adverse events associated with its use, the risks of taking guar gum outweigh its benefits for this indication. Therefore, guar gum cannot be recommended as a treatment for lowering body weight.” Fiber and colon health Does fiber protect the colon from cancer, constipation, and other diseases? No. In the World Journal of Gastroenterology in 2007, Doctors Tan and Seow-Choen published a review of medical studies conducted over the previous 35 years about fiber and colon health and concluded: “A strong case cannot be made for a protective effect of dietary fiber against colorectal polyp or cancer. Neither has fiber been found to be useful in chronic constipation and irritable bowel syndrome. It is also not useful in the treatment of perianal conditions. The fiber deficit-diverticulosis theory should also be challenged…we often choose to believe a lie, as a lie repeated often enough by enough people becomes accepted as the truth. We urge clinicians to keep an open mind. Myths about fiber must be debunked and truth installed.” Ok, so if you are eating a diet that includes high glycemic and refined carbohydrates, soluble (gel) fiber will probably not help you lose weight, but it may soften your blood sugar spikes, and may lower your cholesterol a little. So, since fiber can be helpful in reducing the risks associated with eating a high carbohydrate diet, is there any reason NOT to eat it? Bacteria love soluble fiber We cannot digest the carbohydrates that make up soluble fiber, but the bacteria in our large intestine can, and they do. Undigested carbohydrate fibers arriving in the colon attract huge numbers of bacteria for a free lunch. Is there anything wrong with that? Why not let them enjoy themselves? Well, bacteria don’t exactly digest these carbohydrates, they ferment them, and in the process, they give off gases, like carbon dioxide, hydrogen, and methane. Not only can these gases make you unpopular at parties, but they can also cause uncomfortable cramping and bloating, both common sense signs of poor digestion. Listen to your body: good digestion should not hurt. Yes, you may feel like eating less, but it’s only because soluble fiber swells within your system, attracting a swarm of bacteria, which ferment the fiber and generate a balloon of gases, creating a feeling of fullness. In contrast, animal protein and fat are comfortably and efficiently digested by humans with virtually no gases produced. Soluble fiber extracts are like greedy sponges Once trapped inside of you they require LOTS of water to form the sticky ooze that is supposed to be so good for us. A friend of mine recently told me the story of how she discovered an old container of Metamucil® in the back of her refrigerator that she innocently tried to dispose of by pouring it down the sink. Unfortunately, when she started the water running to flush it down the drain, the psyllium fibers rapidly expanded into a huge, stubborn, constipating blob that her plumber could only dislodge by physically dismantling the pipes. Word to the wise: if you do not drink lots of water along with your soluble fiber supplement, you, too, could find yourself in need of some expensive professional assistance. We were not meant to swallow concentrated extracts of plant fiber. We were designed to eat whole foods. This is why Mother Nature designed juicy, appealing fruits complete with their own water supply. Why do experts believe that fiber is essential for health? It is a simple misunderstanding of the research. Well-meaning, intelligent scientists looked at all the data and came to the wrong conclusion by making a single, critically flawed assumption that led them in the wrong direction. About 150 years ago, the world was populated by two kinds of people: people who were still eating “traditional” diets of various types, and people who were starting to eat a “modern” diet. Good Calories, Bad CaloriesFor the full description of the history and politics of the development of the false fiber theory, I recommend reading the chapter on fiber in Gary Taubes’ Good Calories Bad Calories. The traditional diet folks were eating all sorts of things, depending on where they lived, so their diets varied tremendously from one culture to another. Some ate mostly meat. Some ate meat, and dairy products. Some ate poultry, grains, and vegetables. Some ate fish, coconuts, and fruit. All of these traditional people were incredibly healthy compared to us—all of them enjoyed extremely low rates of cancer; were virtually free of heart disease, diabetes and obesity; sported strong teeth and bones; and had normal blood pressures. The modern diet folks were also eating all sorts of things, depending on where they lived, so their diets also varied tremendously from one culture to another. They also ate some combination of meats, fish, nuts, fruits, vegetables and grains, but what set them apart from the traditional people and what made their diets “modern” was the addition of highly-refined flours and large amounts of sugar. In the 1870s, advances in modern milling technology saw stone grinding wheels replaced with steel rollers, capable of stripping the bran and wheat germ away from the soft center of each grain. This process resulted in the ability to produce ultra-fine, 100% fiber-free particles—the most refined flour in human history. Modern societies had also devised more efficient and less expensive ways to cultivate and distribute sugar to large numbers of people who previously could not afford to buy it. Time after time, when the health of a traditional culture was compared to the health of a modern culture, the traditional culture came out on top, so it was clear to researchers that modern diets were unhealthy. The problem was that some scientists looked at these two types of diets and jumped to the wrong conclusion about why modern diets were inferior to traditional diets. They assumed it was because modern diets were lacking in fiber, not because modern diets were loaded with refined carbohydrates. Now, it is absolutely true that modern diets contained far less fiber than traditional diets did, so they were not wrong about that. Traditional peoples who ate grains ate them whole, stone-ground, or cultured—all forms of grains that have not had their fiber stripped away. However, study after study has shown that adding fiber back to our modern diet does not restore us to the excellent health our ancestors enjoyed. Thus simply eating more fiber in our diet is not the answer. I have yet to see a single scientific study demonstrating that fiber solves any of our problems. At worst, fiber causes constipation, irritation and damage to the inner lining of the intestine, flatulence and pain. At best, fiber reduces blood sugar spikes by ten to twenty percent, reduces LDL cholesterol by about one-third, and promotes a “feeling of fullness”. If you are eating a diet that contains more than a small percentage of sugar and refined carbohydrates, you could eat a truckload of oat bran and still never see your blood sugar, cholesterol level or appetite come down to normal and stay there. Here is an example of the kinds of studies that have been done to show that fiber is healthy: “Whole-grain ready-to-eat oat cereal, as part of a dietary program for weight loss, reduces low-density lipoprotein cholesterol in adults with overweight and obesity more than a dietary program including low-fiber control foods.” [Maki 2010] Sounds promising, until you read the study and learn that there was no difference in weight between the two groups after twelve weeks, that LDL only decreased by about five percent, and waist circumference only decreased by about a half-inch. You read further and discover that the “low-fiber control foods” were refined-carbohydrate junk foods: “participants were randomly assigned to consume either two portions/day (3 c/day) of whole-grain ready-to-eat oat cereal (providing 3 g/day b-glucan) or low-fiber breakfast/snack foods (eg, ready-to-eat corn cereals, white toast, plain bagels and English muffins, pretzels, soda crackers, or rice cakes) with a similar energy and macronutrient content (control group).” It would not be surprising that oat cereal is (perhaps, a tiny bit) healthier than white toast, plain bagels, English muffins and pretzels! However, it is impossible to conclude that the oat cereal was beneficial—it is just as likely that the reason for the very modest benefits seen in the oat cereal eaters was not that they were eating more fiber than the comparison group, but that they were eating fewer refined carbohydrates (sugars and flours) than the comparison group. Or it may be that oats are not as bad for you as wheat and corn. To make matters worse, three of the study’s authors were scientists who worked for General Mills, the manufacturer of Cheerios, the oat cereal used in the experiment! Coming soon to a commercial near you . . . To fiber or not to fiber. . . When you think about it logically, if you wanted to figure out whether or not a particular food is good for humans, you would want to design the study exactly that way—one diet WITH the food and one diet WITHOUT the food. The only study I know of that has dared to completely remove fiber from the human diet yielded remarkable results. In 2012, a randomized controlled trial of 63 people with chronic constipation was conducted in which all participants were placed on a fiber-free diet for two weeks, then were allowed to eat any diet they wished for the next six months. At six months, 41 people were still voluntarily following the fiber-free diet because they had all experienced 100% relief from their symptoms, whereas 100% of those who had gone back to eating fiber continued to suffer from IBS symptoms [Ho 2012]. Cardboard: yes. Delicious: no. bowl of tasteless bran cereal If you still aren't convinced that we are not designed to require fiber, I have no choice but to appeal to your good judgment and common sense. Pour yourself a nice big bowl of wheat bran, grab a spoon and dig in. I don’t mean a bowl of sweetened bran cereal with milk or yogurt or berries on top, I mean a bowl of 100% unsweetened wheat bran. Does it look or smell or taste good to you? Do you like it? Do your kids like it? Can you swallow it? We want to believe in the power of fiber. It is so much easier and so much more appealing to contemplate adding fiber, which is tasteless and indigestible, than to contemplate subtracting refined carbohydrates, which are addictively delicious and fun to eat. The bottom line about fiber pulp fiction book cover showing that fiber is healthy©Suzi Smith, used with permission Fiber is not essential for human life or health. Adding fiber to your diet cannot cure any health problem, because it doesn’t get to the root of the problem. If you eat risky refined and high glycemic index carbohydrates regularly, soluble fiber may soften your blood sugar (and insulin) spikes and may reduce your cholesterol a little by interfering with their digestion. If you find soluble fiber supplements useful, take care to drink plenty of water with them. If fiber bothers your digestive system, or you don’t like eating it, you can safely avoid it, since it is not essential to your health.

Detachin™ Cell Detachment Solution from AMSBIO is a high-performance alternative to Trypsin/EDTA for detaching adherent cells from in vitro growth vessels.

Altamura F., Gaudzinski-Windheuser S., Melis R.T., Mussi M., 2019. Reassessing an early Middle Pleistocene Hippo Butchery Site: Gombore II-2 (Melka Kunture, Upper Awash valley, Ethiopia), in Journal of Paleolithic Archaeology, 32 pp. DOI:

A prospective cohort study published recently in JAMA Cardiology revealed findings that may influence changes in the way risk for coronary heart disease (CHD) is assessed in women. Data were gathered from over 28,000 female health professionals participating in the Women’s Health Study with baseline profiles obtained between 1993 and 1996 with a median follow-up time of 21 years between 2017 and 2020.

Objective: To investigate the relationship between body mass index (BMI) and the breast cancer incidence, so as to making contribution to breast cancer screening in high-risk groups, to adjustment from passive medical treatment to active treatment Methods: BMI status of 206 breast cancer patients and that of 210 healthy subjects at different ages were compared and analyzed. Results: The mean BMI was significantly higher in breast cancer patients than in healthy subjects 24.45±3.50 vs. 23.80±3.10 kg/m2, t=-2.189, P=0.001. When stratified by age, BMI were significantly higher in ≥60 age for breast cancer than that of control group (Z=-3.408, P=0.001) and no significant difference in

Gut microbiota has been implicated in major diseases affecting the human population and has also been linked to triglycerides and high-density lipoprotein levels in the circulation. Recent development in metabolomics allows classifying the lipoprotein particles into more details. Here, we examine the impact of gut microbiota on circulating metabolites measured by Nuclear Magnetic Resonance technology in 2309 individuals from the Rotterdam Study and the LifeLines-DEEP cohort. We assess the relationship between gut microbiota and meta-bolites by linear regression analysis while adjusting for age, sex, body-mass index, technical covariates, medication use, and multiple testing. We report an association of 32 microbial families and genera with very-low-density and high-density subfractions, serum lipid measures , glycolysis-related metabolites, ketone bodies, amino acids, and acute-phase reaction markers. These observations provide insights into the role of microbiota in host metabolism and support the potential of gut microbiota as a target for therapeutic and preventive interventions.

Woolly mammoth bones found in Mexico prove that hunters actually attacked the mammal, instead of waiting for them to die At least 14 skeletons of woolly mammoths have been discovered in Mexico in pits apparently built by human hunters to trap and kill the huge animals some 15,000 years ago, according to Mexico's National Institute of Anthropology and History. The discovery "represents a watershed, a touchstone on what we imagined until now was the interaction of hunter-gatherer bands with these enormous herbivores," Pedro Francisco Sánchez Nava, national coordinator of archaeology at INAH, told reporters on Wednesday. The skeletons were found in Tultepec, about 25 miles north of Mexico City, in clay that had once been at the bottom of Lake Xaltocan. Archaeologist Luis Cordoba Barradas, of INAH's Directorate of Archaeological Rescue, said the discovery offers a more complex and complete concept of how mammoth hunts were carried out. Archaeologists suggested that the clay area had opened up as the lake receded during the era of mammoths, providing hunters with a site easier to dig up to create traps. Cordoba Barradas, who led the team, said the finding suggests that groups of between 20 and 30 hunters swept a herd of mammoths with torches and branches to divert some of the animals into the traps. Once there, they were killed and their carcasses cut up. “There was little evidence before that hunters attacked mammoths. It was thought they frightened them into getting stuck in swamps and then waited for them to die,” he told reporters Wednesday. “This is evidence of direct attacks on mammoths. In Tultepec we can see there was the intention to hunt and make use of the mammoths.” He said an important clue was the vertical cuts in the earth where the bones were found, indicating the pit had been dug by humans. Archaeologists working in the Tultepec sites for 10 months found 824 bones, including eight skulls, five jaws, 100 vertebrae and 179 ribs. Cordoba Barradas said one skull had what appeared to be a long term fracture, indicating that hunters may have battled that particular mammoth for years. He said the way the bones were ritually displayed indicated that the hunters "had to consider him brave, fierce, and showed him his respect in this way." While the 14 mammoths found at the site are far less than the hundred-plus found at sites in northern and eastern Europe, the discovery qualifies Tultepec to be listed as a Mammoth Megasites.

Epigenetic “clocks” can now surpass chronological age in accuracy for estimating biological age. Here, we use four such age estimators to show that epigenetic aging can be reversed in humans. Using a protocol intended to regenerate the thymus, we observed protective immunological changes, improved risk indices for many age-related diseases, and a mean epigenetic age approximately 1.5 years less than baseline after 1 year of treatment (−2.5-year change compared to no treatment at the end of the study). The rate of epigenetic aging reversal relative to chronological age accelerated from −1.6 year/year from 0–9 month to −6.5 year/year from 9–12 month. The GrimAge predictor of human morbidity and mortality showed a 2-year decrease in epigenetic vs. chronological age that persisted six months after discontinuing treatment. This is to our knowledge the first report of an increase, based on an epigenetic age estimator, in predicted human lifespan by means of a currently accessible aging intervention.

Nearly a decade ago, the UN's Food and Agriculture Organization (FAO) developed a new index to assess protein quality in foods. The goal, writ large, was to address food security for the world's most vulnerable populations, creating more accurate tools for food assistance programs seeking to provide balanced nutrition.

Right to Hunt vs. Animal Rights: Legends of the Fall A Daily Reckoning Special Position Paper by Jim Amrhein "The encouragement of a proper hunting spirit, a proper love of sport, instead of being incompatible with a love of nature and wild things, offers the best guaranty for their preservation." -- U.S. President and Nobel Prize [...]

There is a simple reason we strongly promote science-based medicine – it results in the best outcomes for individuals. That is true by definition, since the SBM approach is to use the best evidence

A study from the Netherlands indicated higher consumption of salt was associated with accelerated disease progression for patients with autosomal dominant polycystic kidney disease. This effect was not seen with higher protein intake. According to Bart J. Kramers, MD, of the University of Groningen, and colleagues, limitations on salt intake are recommended for patients with chronic kidney

The nerve cells, also called neurons, in our brain control all the basic processes of our body. For this reason, there are different types of neurons distributed over specific regions of the brain. Researchers have now developed an approach that allows them to show that neurons that are supposedly the same are actually very different: they not only sense different hormones for the body's energy state, but also have a different influence on food intake. This can have a direct effect on our metabolism, for example by differentially restraining our appetite.

Pioneering mouse study offers new therapeutic avenues for reducing visceral fat stores, which have been associated with cardiovascular disease and multiple types of cancer.

Researchers have identified the biological mechanism that explains why some people experience abdominal pain when they eat certain foods. The finding paves the way for more efficient treatment of irritable bowel syndrome and other food intolerances. The study was carried out in mice and humans.

Background: The failing heart is energy-starved with impaired oxidation of long chain fatty acids (LCFA) at the level of reduced carnitine palmitoyltransferase 1 (CPT1) activity at the outer mitochondrial membrane. Recent work shows elevated ketone oxidation in failing hearts as an alternate carbon source for oxidative ATP generation. We hypothesized that another short chain carbon source, short chain fatty acids (SCFA) that bypass CPT1, could similarly support energy production in failing hearts. Methods: Cardiac hypertrophy and dysfunction was induced in rats by transverse-aortic constriction (TAC). 14 weeks after TAC or sham-operation, isolated hearts were perfused with either the four carbon, 13C-labeled ketone (D3-hydroxybutyrate) or the four carbon, 13C -labeled SCFA, butyrate in the presence of glucose and the LCFA, palmitate. Oxidation of ketone and SCFA was compared by in vitro13C NMR spectroscopy, as was the capacity for short chain carbon sources to compensate for impaired LCFA oxidation in the hypertrophic heart. Adaptive changes in enzyme expression and content for the distinct pathways of ketone and SCFA oxidation were examined in both failing rat and human hearts. Results: TAC produced pathological hypertrophy and increased the fractional contributions of ketone to acetyl CoA production in the tricarboxylic acid cycle (0.60±0.02 sham ketone vs 0.70±0.02 TAC ketone, p

Patients with type 2 diabetes who follow a strict low carbohydrate diet for six months may experience greater rates of remission compared with other recommended diets without adverse effects, a new study suggests.

Sistiaga, A., Berna, F., Laursen, R., Goldberg, P.2014. Steroidal biomarker analysis of a 14,000 years old putative human coprolite from Paisley Cave, Oregon

Sistiaga, A., Mallol, C., Galván, B., Summons R. 2014. The Neanderthal Meal: a New Perspective using Faecal Biomarkers.

Our understanding of early human diets is based on reconstructed biomechanics of hominin jaws, bone and teeth isotopic data, tooth wear patterns, lithic, taphonomic and zooarchaeological data, which do not provide information about the relative

BackgroundElevated plasma levels of direct low‐density lipoprotein cholesterol (LDL‐C), small dense LDL‐C (sdLDL‐C), low‐density lipoprotein (LDL) triglycerides, triglycerides, triglyceride‐rich lipoprotein cholesterol, remnant lipoprotein particle cholesterol, and lipoprotein(a) have all been associated with incident atherosclerotic cardiovascular disease (ASCVD). Our goal was to assess which parameters were most strongly associated with ASCVD risk.Methods and ResultsPlasma total cholesterol, triglycerides, high‐density lipoprotein cholesterol, direct LDL‐C, sdLDL‐C, LDL triglycerides, remnant lipoprotein particle cholesterol, triglyceride‐rich lipoprotein cholesterol, and lipoprotein(a) were measured using standardized automated analysis (coefficients of variation, <5.0%) in samples from 3094 fasting subjects free of ASCVD. Of these subjects, 20.2% developed ASCVD over 16 years. On univariate analysis, all ASCVD risk factors were significantly associated with incident ASCVD, as well as the following specialized lipoprotein parameters: sdLDL‐C, LDL triglycerides, triglycerides, triglyceride‐rich lipoprotein cholesterol, remnant lipoprotein particle cholesterol, and direct LDL‐C. Only sdLDL‐C, direct LDL‐C, and lipoprotein(a) were significant on multivariate analysis and net reclassification after adjustment for standard risk factors (age, sex, hypertension, diabetes mellitus, smoking, total cholesterol, and high‐density lipoprotein cholesterol). Using the pooled cohort equation, many specialized lipoprotein parameters individually added significant information, but no parameter added significant information once sdLDL‐C (hazard ratio, 1.42; P

IBS, or irritable bowel syndrome, causes you to drastically change your diet because of unpleasant symptoms associated with certain foods. Because of this change in diet it is important to make sure you are receiving enough nutrients, fiber, and protein. You can find these nutrients in soy, and it is a good choice for people with IBS. If you...

In honor of National Colon Awareness Month, let's talk about soy -- soy as  an incomparable gas pro...

A diet high in soybean oil causes more obesity and diabetes than a diet high in fructose, a sugar commonly found in soda and processed foods, according to a just published paper by scientists at the University of California, Riverside.