I've heard that if you want to lose weight you should refrain from eating after 8pm. I've also heard that it doesn't matter when you eat, as long as the total number of calories does not exceed your daily requirement. Which is correct?

The health professionals who told you it doesn't matter when you eat believe that all that counts in weight management is calories. These folks believe that a calorie is a calorie is a calorie -- that it doesn't much matter where that calorie comes from or when it's eaten as long as the total amount taken in is less than the amount you're burning up.

In my opinion, that view is extremely dated. It misses a big part of the picture and doesn't stand up to clinical experience.

For one thing, the "calories are all" theory completely ignores the fact that what you eat -- the composition of your meals -- has a profound effect on hormones that your body releases, namely insulin and glucagon. The balance between these hormones is crucial to weight-loss success. High-carbohydrate meals stimulate more insulin than balanced, or low-carbohydrate, meals. Timing also seems to make a difference. In one study, for example, all participants ate the exact same 2,000-calorie meal once a day. One group ate in the morning and the other at night. The group who ate at night gained weight, while the morning group did not. If calories were the only thing that counted, it shouldn't have mattered when they ate them.

A large meal before you go to bed -- especially one high in carbs -- stimulates insulin, which in turn stimulates fat storage and definitely prevents "fat burning." A tried and true strategy in weight management is to cease eating as early in the evening as is both possible and practical -- a strategy that works quite well for most people. If you just can't go to bed on an empty stomach, stick with a small snack that has protein and some fat but is low in carbs; eat just enough so that you're not too hungry to sleep.

Better yet, try not eating after 7 or 8 and see what happens.

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