Comparison between the American diet and the French diet, from Wikipedia under The French Paradox:
Clower tends to play down the common beliefs that wine consumption and smoking are greatly responsible for the French paradox. The French diet tends to cause Americans to lose weight while visiting even if they are not wine drinkers. While a higher percentage of French people smoke, this is not greatly higher than the U.S. (35% in France vs. 25% in U.S.) and is unlikely to account for the weight difference between countries.Mirreille Guiliano, author of the #1 bestseller French Women Don't Get Fat, agrees that the weight differences are not due to French smoking habits. She points out that the smoking rates for women in France and the US are virtually identical. Guiliano explains the key factors to the French woman's ability to stay slim as:
What's interesting is how closely this relates to the diet I personally believe in, which includes abolishing the concept of frequent small meals (grazing), eating more natural foods with natural fat contents, avoiding sugar and manufactured low-fat fares and pre-made food packages, eating fresh foods, and small but a wide variety of quality foods, rather than large and unvaried amounts of low-quality foods (such as pasta, breads and cereals).