Review Article
What Should We Eat? Evidence from Observational Studies
Abstract
Observational studies provide a wealth of important correlations between diet and disease. There is a clear pattern of dietary habits that is associated with reduced rates of a multitude of common illnesses, including heart attack, cancer, stroke, diabetes, and hypertension. In some cases, interventional studies have proven the benefits of dietary change; in others, there is insufficient evidence to prove causation. Based on the existing evidence, the optimal diet should emphasize fruits and vegetables, nuts, unsaturated oils, whole grains, and fish, while minimizing saturated fats (especially trans fats), sodium, and red meats. Its overall calorie content should be low enough to maintain a healthy weight.
Key Points
* Diet contributes directly or indirectly to the rates of seven of the top ten causes of death in the United States.
* The same healthy dietary habits are associated with reduced rates of a multitude of different diseases.
* The overall benefits from positive lifestyle factors could account for up to a 10 year difference in life expectancy.
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