From federal investigations into Major League Baseball to allegations of substance abuse in track and field, performance enhancing drugs have been in the news a lot. The most well-known performance enhancers are steroids--drugs that can make athletes bigger and stronger. But they can also cause serious medical problems.
So how do steroids work, and what makes them so dangerous?
First, it's important to understand that the body naturally produces steroids. For men, the best known is testosterone. Testosterone is an anabolic steroid, meaning that it encourages new muscle growth. So the more testosterone you have in you, the greater potential you have to be bigger and stronger. It makes sense, then, that artificial anabolic steroids mimic testosterone produced in the body.
Here's how they work: Anabolic steroids attach to cells and encourage them to produce more protein, which muscles need to grow and become stronger. So steroids basically speed up and enhance the process of muscle growth that you can accomplish by lifting weights and other kinds of exercise. A weightlifter on steroids will develop larger muscles and do so faster than a "clean" weightlifter.
Millions of people take performance enhancing drugs such as caffeine and vitamins every day. But unlike these drugs, steroids can cause serious, long lasting problems. For example, steroid use puts extra pressure on the liver to cleanse the bloodstream of the many toxins in steroids. Prolonged steroid use can result in liver damage. They also affect brain chemistry, and can cause depression and severe mood swings known as 'roid rage.'
There's certainly nothing wrong with building your body, but using steroids to do so will ultimately weaken your body in the long run.
"How Performance-enhancing Drugs Work" (How Stuff Works)