lunch habits causing weight gain

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Your Lunches Are Making You Hungrier for Dinner (But Not for the Reason You Think)

Why it packs on pounds: Large lunches don't just have excess calories; they may prime your brain for large dinners—at least that's what researchers found when they overfed both lean and obese mice; their results suggest that eating too many calories at once stops the production of a hormone that normally sends fullness signals to the brain. Which means you might not be satisfied by your lunch—and, chances are, you're going to gorge on whatever's around once you get home.

The fix: Stop eating when you feel comfortably full but not like you overdid it. Try to follow these guidelines from Lori Zanini, RD, spokesperson for the Academy of Nutrition and Dietetics: three to four ounces of a lean protein, such as grilled chicken or fish, a healthy carb like fruit or whole grains, one to two tablespoons of good fats, such as olive-oil based salad dressing or nuts, and as many vegetables as you want.