Julianne Taylor has a fascinating blog post based on a trip to France and Great Britain. Julianne is a dietitian living in New Zealand. Please read the entire article.
Her conclusions:
“What can we learn from the French way of eating?
Don’t snack. At all. Eat 3 balanced meals, and snack only if needed.
Planned snacks are fine, children always have an after school snack, or small meal in France. Treat the snack with the same respect as you would a meal.
Don’t eat anywhere other than at a table. Don’t eat walking around, at your desk, in front of the TV, or snack out of the fridge. Prepare, then eat a meal at a table, preferably with company and actually experience the process of savoring your food. Eat slowly.
Choose food freshly prepared from whole ingredients like protein, fruit and vegetables.
Model eating like this to your children, and don’t push them into our bad habits. Enjoy family meals together at the table without any screens or phones.
Treat food is fine, savor a small portion as part of a meal if you wish.
Water should be the main drink, wine in moderation can be enjoyed with meals if desired,”
Source: Eating habits in France, what we should copy | Julianne’s Paleo & Zone Nutrition
Diabetic Mediterranean Diet 
So eat less and move more to prevent obesity.
Eat less and move more to prevent obesity.
I think the fact that they eat more fat, especially dairy fat, and whole foods as opposed to food stuffs like processed foods and only do this 3 x per day is a key. They loathe the kind of exercise that Americans think is the holy grail of health and instead walk more casually and more often than we do. Also, since their meals are more nutrient dense, their portions are smaller.