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Top 10 Physical Energy Zappers

Dietary Choices
The birthday party sugar crash.
The birthday party sugar crash.
Sabine Duerichen/LOOK/Getty Images

­You want to lose a few pounds, so you've gone on a low-calorie diet. But instead of heeding advice about how many calories you need to consume in a given day, you've decided to give up calories entirely. That should help you lose weight faster, right? Wrong -- this kind of unhealthy choice causes your body to go into starvation mode. Not only will you not lose weight, you'll experience an immediate drop in energy as well. Your body tries to conserve the little energy that it has left by storing all calories as fat and throwing your muscle on the energy fire.

But obviously, excess food isn't the answer either. Too much food depletes energy, especially when those extra pounds start appearing, a phenomenon we'll discuss later. And while sugary food may promise a quick rush of energy, it also provides a crash that comes just as quickly. A sweet treat like a candy bar causes a huge release of insulin, which lowers blood sugar and leaves you feeling sluggish. For the most energy all day long, you should consider small snacks and meals every few hours that will keep your sugar levels at an even keel.

Dietary choices include the beverages you consume, but this category is so important that we've dedicated an entire page to it. Next, find out what you should be drinking with your healthy snacks.