The French Diet basically focuses on keeping the number of times you eat each day low -- typically breakfast, lunch and dinner, and, at most, one snack. (That's basically the opposite of more mainstream approaches like Body for Life, which advocates eating six small meals spread throughout the day, obstensibly to keep your metabolism high.) The French diet also focuses on keeping portion sizes very small (by American standards). So, in a nutshell, it is basically a rather low-calorie diet. I think the biggest obstacle to a program like that for me would be psychological, in that it seems to rely heavily on having been brought up in a culture where those things (no snacking and very small portion sizes) were the norm.