Sebastoem Czernichow is a French nutrition researcher cheering on America's flurry of federal, state, and local laws and initiatives against obesity. What some call the food police, he calls progress. The prevalence of obesity in his nation is leveling off after a decade of government interventions.

"I want to be cautious, but we're seeing early signs that even though we're still having a global rise in prevalence, we may have created a protective environment in France,'' said Czernichow.

In the United States, the fattest developed nation in the world, the new national health care law calls for large restaurant chains to post calorie counts on menus and signs, similar to what Massachusetts and other states and cities have already mandated. First Lady Michelle Obama's obesity crusade has soda companies playing defense, running ads to boast how they are removing sugary drinks from schools.

Last month, the Massachusetts Legislature approved a bill that will effectively end the sale of sugary drinks and trash food in schools. Boston was awarded $12.5 million in stimulus funds to fight obesity and smoking and Massachusetts received another $633,000 in stimulus money to bolster its state menu labeling program and promote physical activity at child-care programs.

But it is still a chaotic patchwork thrown at a sweeping epidemic and against a marketing assault on children by fast-food and soda companies that amounted to $1.6 billion in 2006, according to a 2008 Federal Trade Commission report. Our efforts remain well short of France's laws and initiatives that included banning vending machines from schools and replacing them with water tanks, putting warning labels on unhealthy foods, and requiring food companies to run warnings on television, radio, and billboard advertisements.

The warnings tell consumers to avoid snacks, excess sugar, fats, and salt and urge people to exercise. Companies that do not run warnings must pay the government a 1.5 percent tax on the cost of their ads. Because of the tax, few companies refuse to run the warnings, Czernichow said. That strategy should be considered in the US, where the trash-food lobby has thus far warded off national point-of-sale "fat taxes.''

Recent data indicate that obesity has not increased since 1998 for children of higher socio-economic groups in central and western France, and began stabilizing for even low-income youth in 2001. A study last year co-authored by Czernichow in the International Journal of Obesity said this was "encouraging'' enough to suggest a "true plateau'' in obesity. He said the findings coincide "with increasing information on childhood overweight in France.''

In an interview, Czernichow emphasized that it will take five-to-10 more years to determine if the leveling off is directly due to concentrated government campaigns. But he shudders to think what would have happened without them. The French level of adult obesity is about a third of the US, but restaurant portion sizes in France, influenced by the US, have been growing.

"It suggests that you cannot focus on just one thing,'' Czernichow said. "The effort has to be everywhere and constantly, parallel to tobacco where you had class actions, banning smoking from public places, and increasing the price of cigarettes. It was a multiple action system that had cumulative effects.''

Czernichow said he wonders if the United States will see those effects, especially after recently eating in Boston restaurants. Massachusetts is the second-least obese state in the nation, yet, Czernichow observed: "The energy density of the food in your restaurants is so high and the portion sizes are amazing, not only for fast foods, but in your healthier seafood restaurants. I ordered swordfish at one restaurant and the dinner would have fed me, my wife and my two kids.

"I had lunch in the South End. What you call appetizers, we call dinner. The salad was so high on my plate. I talked with the waiter and we laughed because I thought I was on some kind of reality show with a hidden TV camera, seeing how much I would eat.'' Even as Czernichow laughs, it makes you question whether our patchwork of initiatives can work in the fight against fat.