When you're looking to tone up those muscles, what's the best protein you can eat? It may sound surprising, but eggs are considered to have the highest-quality protein found in food. In fact, egg protein is actually used as the standard to which other proteins are compared. A little more than half of the protein in an egg is found in the fat-free white, so you can load up on egg whites practically guilt-free!

Eggs pack a strong nutritional punch besides their protein content: The yolks are a great source of easily absorbable lutein, an important antioxidant (also found in spinach and other green vegetables) that's great for your eyes and your skin. And although the yolks do contain fat, it's mostly unsaturated — the healthy kind of fat.

By the way, the theory that eggs increase cholesterol levels in the bloodstream has been thoroughly debunked. A recent study found no difference in heart disease risk between those who ate one egg a week and those who ate one a day. Another study concluded that eating two eggs a day for six weeks had no impact at all on cholesterol levels. The key is to prepare your eggs healthfully — large amounts of butter, cheese, and cream in the company of sausage and bacon aren't good for your cholesterol level or your abs!

Here's some welcome news for breakfast lovers: Eggs may help reduce your weight.

Eggs already have been reinstated as a health food (the major Nurses' Health Study cleared eggs of upping heart attack and stroke risk). Now there's evidence that people who scramble, boil, or poach one for breakfast -- versus eating a bagel with the same number of calories -- bypass junk-food cravings and eat fewer calories for at least 24 hours, without even trying.

Thanks to what turned out to be a bad cholesterol rap, you may have avoided eggs for years. But eggs have always been a good source of nutrients and protein. And for reasons that aren't completely clear, it turns out that they make the body feel fuller longer. In one study, people with weight problems who started the day with an egg were still eating fewer calories than normal by lunch the following day. You know that line about "the incredible, edible . . ."? Looks like the jingle writer had a clue.

References: Short-term effect of eggs on satiety in overweight and obese subjects. Vander Wal, J. S., Marth, J. M., Khosla, P., Jen, K. L., Dhurandhar, N. V., Journal of the American College of Nutrition 2005 Dec;24(6):510-515.