By Paul Goldfinger, MD, FACC.
In a recent BF article about the health benefits of fresh produce, I stated that there was very little hard science behind the claims for fruits and vegetables specifically.
Fruits and vegetables for prevention BF article
But a large randomized trial from Spain of 7,400 individuals was published in the New England Journal of Medicine on April 4, 2013. There were men (ages 55-80) and women (ages 60-80) enrolled in the study. It showed a 30% risk reduction in cardiovascular endpoints as a result of following Mediterranean diets which include fruits and vegetables among its components. These end points included heart attack, stroke, and death due to cardiovascular causes.
The study looked at “high risk” individuals with no overt cardiovascular disease. The trial participants had Type 2 diabetes or at least 3 major risk factors such as high blood pressure, high cholesterol, family history of early heart disease, smoking or obesity. The trial was terminated early after nearly five years because the results were so striking.
The control group, which followed a low fat diet, did not show a benefit. There were two treatment groups that did show the benefit. They adhered to a Mediterranean diet consisting of fruits, vegetables, extra-virgin olive oil, nuts, cereals, legumes and fish.
One group emphasized nuts ( 30 grams per day of walnuts, hazelnuts and almonds—about one palm full each day), while the other group used extra virgin olive oil (about 4 1/2 ounces per day). The two “treatment” groups also ate poultry, but very little red meat or processed meats, and little in the way of sweets or packaged baked goods like cookies and cake.
Exercise was not part of the study protocol, nor was caloric restriction, although those components are certainly important for any prevention plan.
The precise way that such diets improve risk was not studied here, but there is a lot of evidence that suggests mechanisms. The authors of this trial said, “Perhaps there is a synergy among the nutrient-rich foods included in the Mediterranean diet that fosters favorable changes in intermediate pathways of cardiometabolic risk, such as blood lipids, insulin sensitivity, resistance to oxidation, inflammation, and vasoreactivity.” (Feel free to comment below if you need further translation of these remarks by the Spanish doctors who conducted this valuable trial)
The report summed it up by saying, “In conclusion, in this primary prevention trial, we observed that an energy-unrestricted Mediterranean diet, supplemented with extra-virgin olive oil or nuts, resulted in a substantial reduction in the risk of major cardiovascular events among high-risk persons. The results support the benefits of the Mediterranean diet for the primary prevention of cardiovascular disease.”
In our book “Prevention Does Work: A Guide to a Healthy Heart” (2011, iUniverse) we advocate a Mediterranean diet for prevention and we teach about it and offer 36 heart healthy recipes to help anyone who wants to make this important life style change. You can get the paper back version on Amazon.com, Barnes and Noble.com, and iUniverse.com. It costs about $12.00. Just search under Paul Goldfinger, MD or “Prevention Does Work.”