Whey Protein: What You Need to Know

Could increasing your intake of whey protein give you muscles like these? See more staying healthy pictures.
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­Little Miss Muffett

Sat on a tuffet,

Eating her curds and whey.

Along came a spider

Who sat down beside her

And said, "Hey, nice pecs!"

Today's consumer of whey protein is more likely to be a bodybuilder than the arachnophobic heroine of a nursery rhyme. But the food is the same -- sort of. Curds and whey were probably something like cottage cheese. Whey protein is a nutritional supplement that comes from milk. It's isolated from the rest of the milk through various purification processes.

Only 20 percent of milk's protein is whey. The rest is casein (itself an ingredient of many other protein supplements). Casein is the protein that triggers most milk allergies, so whey protein -- if it's relatively pure -- may be a way for people with allergies to get dairy proteins into their diets. However, it can still set off some allergic reactions, and it can trigger lactose intolerance as well, so proceed with caution.

­The makers of nutritional supplements tout whey protein as a way to build lean muscle mass, recover from workouts and lose weight. Some doctors urge caution, though. No one questions that whey protein can be an effective source of dietary protein, but do you need it at all? And what happens if you don't need it and consume it anyway?

This article will tell you a bit more about whey protein, which could offer benefits to weightlifters and dieters alike. But it can cause some side effects that are a bit scarier than spiders. Read on.