What's the Best Diet for Weight Loss?

Many books about weight-loss diets have been written over the last several generations, and all have been touted as being  "the best" by their advocates. The problem has been that we have lacked  high-quality, comparative studies to really compare how effective these diets really are in losing weight and  keeping it off. A new study that was just released now goes a long way to solve that problem!

Israeli researchers compared three diets — a low-fat, calorie-restricted diet based on the guidelines of the American Heart Association , a moderate-fat, calorie-restricted, Mediterranean diet, and a low-carbohydrate non–calorie-restricted diet based on the Atkins diet. The research was done in a randomized fashion, using  322 moderately obese adults, and 86% of the subjects were male. The trial was based at a workplace where lunch was served as the main meal of the day, and tailored to the three diets being studied. Study participants met frequently with dieticians, to review and plan their other meals, in order to be sure they were folowing the appropriate eating plan.

After 2 years, there was a big diffference among the groups! Average weight loss was significantly greater in the low-carbohydrate and Mediterranean groups than in the low-fat group. Just as importantly, lipid levels were also better! HDL (good) cholesterol levels increased and LDL (bad) cholesterol levels remained similar in each group, but the ratio of total cholesterol to HDL cholesterol improved most in the low-carbohydrate group. Blood sugar was also measured. Among 36 diabetic participants, fasting glucose improved most with the Mediterranean diet. People really stuck with these diets due to the close follow up and help they received. Adherence rates at 2 years were 90% in the low-fat group, 85% in the Mediterranean group, and 78% in the low-carbohydrate group. Only 16% of the participants withdrew from the trial.

This study clearly demonstrates  that  low-carbohydrate and Mediterranean diets are more effective alternatives to the traditional low-fat diets, and that they even improve lipids and blood sugar results. Since this trial had a  long duration and a high adherence rate, it is an important addition to the literature that all of us contemplating weight loss should consider. Your family doctor can help you get on  the right path!

Reference:
Shai I et al. Weight loss with a low-carbohydrate, Mediterranean, or low-fat diet. N Engl J Med 2008 Jul 17; 359:229.