Adherence to a healthy lifestyle, particularly a well-balanced diet, protects against the development of type 2 diabetes (T2D), with differences across ethnicities, suggests a US study.
Researchers assigned participants in a subset of the Multiethnic Cohort study from five ethnic groups (aged 60‒77 years) a Lifestyle Risk Factor Index (LSRI) score: one point each for consuming <1 (women)/<2 (men) alcoholic drinks/day, ≥1.5 physical activity hours/week, not smoking, and adhering to ≥3/7 dietary recommendations.
Participants then completed an extensive Quantitative Food Frequency Questionnaire to allow estimation of adherence to intake recommendations for fruits, vegetables, refined and whole grains, fish, processed and nonprocessed meat.
Self-reports and fasting glucose were used to classify glycaemic/T2D status. The researchers used logistic regression to assess the prevalence odds ratios (POR) of LSRI with glycacemic /T2D status and DXA- and MRI-based body fat distribution.
A total of 1,713 participants were included, of whom 43 percent had normoglycaemia, 30 percent pre-T2D, 9 percent undiagnosed T2D, and 18 percent T2D. Only 12 percent of the participants scored 4 LSRI points, while 49 percent and 39 percent scored 3 and 0‒2 points, respectively.
Participants who scored 4 LSRI points had a 55-percent lower T2D prevalence (POR, 0.45, 95 percent confidence interval, 0.27‒0.76) than those with 0‒2 LSRI points, with weaker associations for abnormal glycaemic status.
Notably, there was low adherence to dietary recommendations (22 percent), which was the only factor associated with lower T2D prevalence. Ethnic-specific models showed that the inverse LSRI-T2D association occurred only among Latinos and Japanese Americans.
Additionally, T2D patients showed higher visceral fat measures, which attenuated the association between LSRI and T2D.