If you stick with a Mediterranean or low-carbohydrate diet, you’ll be healthier in the long run even if you regain a few pounds after years on the plan, according to a follow-up study by Israel’s Nuclear Research Center and Ben-Gurion University of the Negev (BGU).
The results of the study, published last week in a peer-reviewed letter in the New England Journal of Medicine, updated the findings from the landmark 24-month Dietary Intervention Randomized Controlled Trial (DIRECT).
In the DIRECT study, 322 moderately obese subjects were randomly assigned to one of three diets available at home and in their workplace cafeteria: low fat, restricted-calorie; Mediterranean, restricted-calorie; or low-carbohydrate, non-restricted-calorie.
The Mediterranean diet is based on traditional eating habits of Greeks, Israelis and other Mediterranean-area nations. It emphasizes fruits and vegetables, whole grains, legumes, seeds and nuts, olive oil, herbs and spices instead of salt, and moderate amounts of red wine. Fish and poultry are included in meals at least twice a week, while red meat is limited to no more than a few times a month.
While all three approaches led to a healthy reduction of blood pressure, the low-carb and Mediterranean diets showed especially beneficial metabolic effects of lower cholesterol, triglycerides and arteriosclerosis. Apparently, these results weren’t just temporary.
Looking beyond initial results
“Our follow up subsequent data shows lasting, positive effects of Mediterranean and low-carbohydrate diets six years later,” said Dr. Dan Schwarzfuchs from the Nuclear Research Center in Dimona, where the research on 259 of the original participants was conducted.
The significance of the Israeli follow-up study is that data from trials comparing the effectiveness of weight-loss diets rarely go beyond the initial intervention period, explained BGU researcher Iris Shai, a registered dietician.
In the four-year post-intervention, each DIRECT participant regained nearly six pounds. During the entire six-year period, including the initial study, participants lost approximately six-and-a-half pounds on the Mediterranean diet and 3.7 pounds on a low-carb diet. More than two-thirds of the participants continued with their original assigned diet.
The researchers also found that after six years, the HDL/LDL cholesterol ratio remained significantly lower only in people on the low-carbohydrate diet, while triglyceride levels remained significantly lower in both the Mediterranean and low-carbohydrate diets.
The researchers are now performing a new long-term dietary intervention trial to trigger weight-loss mechanisms using a range of dietary strategies and novel techniques.