Diet & Diabetes Prevention: Does the Specific Diet Matter?

Approximately 90% of diabetes seems to be related to lifestyle, with poor diet a leading cause. Americans tend to eat too many calories, and even those who manage to stay slim often do so eating diets high in fats and protein. The American Diabetes Association recommends eating fewer calories of better quality to prevent diabetes. Researchers looked at the available evidence from studies that examined a variety of diets and found that any healthy diet reduces the risk of diabetes by about 20%.

This meta-analysis, which appears in the journal Endocrine, included only prospective cohort studies that assessed associations between diet and prevention of type 2 diabetes (T2DM). Among the diets employed were the Mediterranean diet, Mediterranean diet supplemented with free extra virgin olive oil or nuts, low-fat diets and Dietary Approaches to Stop Hypertension (DASH). After isolating 18 studies, their results are based on 21,372 cases of incident diabetes. Studies were conducted in the United States, Europe, Asia and Australia.

Risk of incident diabetes was similar regardless of geography (USA, Europe, and Asia). Results also remained the same even in the shortest studies; following a healthy diet for fewer than 10 years reduced the risk of diabetes by 20%, as did longer durations.

An interesting finding was that in two cohorts—Italian patients who had recently had a myocardial infarction and women with previous gestational diabetes—diet reduced risk the most (RR= 0.69).

All diets shared certain components. They usually included emphasis on whole grains, fruit, vegetables, nuts, legumes, healthy table oils (i.e., olive oil), avoidance of processed and red meat with preference for other protein sources, little or moderate alcohol intake, and reduced sugar- sweetened beverages. The authors note that these components may have synergistic effects. They conclude by noting that the many diet plans available are well able to accommodate personal preferences (eg, tradition, culture, religion, health beliefs and goals, and economics). The bottom line: healthy eating works.