Tokelau

https://www.frontiersin.org/articles/10.3389/fnut.2022.748305/full

Diet

The traditional diet was mainly coconuts and fish, with very high total fat (53%) of which 85% was SFAs (77, 79). The prospective TIMS followed most Tokelauns over >18 years (74). The New Zealand migrant diet was 15–20% higher in calories; meat and dairy increased from 1 to 32% of calories. Fat consumption declined 13% and SFA declined 23%; carbohydrates increased 25%, protein increased 25%, MUFAs increased 320% and PUFAs increased 33% (64). Sugar consumption increased in Tokelau and New Zealand; far more for migrants (650; 2 to 13% calories) than non-migrants (400, 2 to 8%) (64, 80).

Activity and Lifestyle

Lifestyles differed by gender. Men fished with oared canoes, gathering coconuts, and did work in village but activity declined post-transition on Tokelau as 8–12 h oar-powered canoe trips were reduced to 2–3 h on motorized dinghies (65, 77). As imported foods increased, the work to harvest coconuts, remove their shell and process the copra fruit declined. Migrant men in New Zealand were in active in railway casting shops, forest services and other jobs (77, 81). In Tokelau, women had relatively sedentary lifestyles before and after the transition, as homemakers who prepared and wove plant fibers into mats while sitting and socializing (65). The reported level of activity may underestimate women's activity. In New Zealand, women worked in electrical assembly, clothing factories and cleaning offices, often walking long distances to and from work (77). Automobiles and public transportation in New Zealand partially offset increased activities.

Post-transition 21% of Tokelau men regularly drank alcohol while few women did. In New Zealand (1968–1971), average alcohol consumption increased from 4.3 days/month to 6.7 days/month (63). By 1982, 73% of men and 29% of women Tokelauans in New Zealand regularly drank alcohol (64). In Tokelau (1977), 62% of men and 26% of women smoked cigarettes; in New Zealand (1982), 63% of men and 36% of women smoked (77).

Health Outcomes

In 1928, before western foods reached Tokelau, the population had “low levels of coronary heart disease, obesity and diabetes” (64). Blood pressures were low and showed minimal elevation with age. In 1968, the group that migrated to New Zealand was younger (men averaged 11 years and women averaged 7 years) than non-migrants. Ten to 14 years after migration, this younger cohort's BMI increased 19% in men and 14% in women, while the older cohort in Tokelau had BMI increases of 5% in men and women (82). Diabetes prevalence rose in all Tokelau cohorts from 1968 to 1982; in Tokelau from 3.2 to 6.9% in men and from 8.7 to 14.3% in women, in New Zealand from 7.5 to 10.8% in men and 11.7 to 19.9% in women (77).

Cholesterol levels declined slightly from 1968 to 1982 for all Tokelauns for both sexes in Tokelau and New Zealand. In 1968/71, the older non-migrant cohort had slightly higher cholesterol levels than migrants (men 215 vs. 205; women 222 vs. 201) and 1982 (men 191 vs. 185; women 205 vs. 189), attributed to age and higher coconut and SFA consumption in Tokelau. Triglyceride levels rose but remained >30% higher in the younger migrants in 1968/71 (men, 49.5 vs. 27.4) and 1982 (men, 54.5 vs. 41.8). A similar trend was seen in women. The younger migrant cohort had higher LDL and lower HDL than the older migrants after 14 years; more in men than women (64). Over the 14 year study, blood pressures was relatively stable; for older subjects in Tokelau, from 123/71 to 128/74 (men) and 128/75 to 132/77 (women), and for younger migrants, from 121/70 to 129/78 (men) and 120/74 to 129/77(women) (65).

Heart disease was more common in the younger migrants despite their lower cholesterol and smoking rates than in the non-migrants in Tokelau. Electrocardiographic (ECG) evidence of myocardial infarction was found in 1% of migrant men but in no non-migrants. Milder ECG abnormalities were found in 15.6% of migrant men and 8.7% of the older men on Tokelau (77).