It can happen suddenly or slowly over time, but when you put on a few unexpected pounds, you may find yourself scratching your head and wondering how you managed to gain weight. Unless you've started eating desserts after every meal or binging at buffets on a nightly basis, it can be hard to figure out where you went wrong.
You're eating more calories than you think. Even if you think you're watching what you eat, you may actually be consuming more calories than you realize. The culprit? Portion sizes. Consider this: ten years ago, the average bagel was the size of a fist. Now, a bagel can be as big as a small salad plate-nearly tripling the amount of calories in a serving size.
You're not getting enough sleep. The optimal amount of sleep is eight hours a night, every night. But if you get less, the body senses that something is off-kilter and tends to want to hold on to excess fat instead of burning it.