Jason Giambi (now a Cleveland Indian) admits to taking it during his 2002 and 2003 seasons with the Yankees; A-Rod is off the field for all of 2014 because of his association with the banned substance; and many other athletes have tried to improve their performance by taking it. We're talking about HGH, or human growth hormone, a protein produced by the pituitary gland that fuels bone and cartilage growth in kids and, as a supplement, is supposed to be a "magic elixir" that fights aging and injury.

But taking HGH supplements can cause swelling in arms and legs, joint and muscle pain, breast enlargement in men, heart disease and diabetes, and may trigger growth of cancer cells, not to mention suspension from the team! Plus, studies don't prove supplements boost strength or reverse aging. The good news: You can increase your HGH levels naturally.

Do resistance exercises: Use hand weights or resistance bands three times a week for up to 10 minutes. Feel the burn? You're stimulating HGH production.

Sleep deep for 7-8 hours: You get max HGH production a couple of hours after you fall asleep. To sleep well, don't eat for two hours before turning in; turn off the TV, computer and phone; and get your bedmate to follow these guidelines, too!

Eat foods packed with the four HGH-stimulating amino acids: glycine in chicken breasts, watercress and spinach; ornithine from fish and low-fat dairy; arginine from crabs, spinach and turkey (skinless); and lysine from chicken (skinless), fish, parsley and spirulina seaweed.