• Lose fat, gain muscle
• Increase energy level
• Increase immune function
• Enhance sexual performance
• Increase cardiac output
• Improve skin elasticity
• Remove wrinkles
• Eliminate cellulite
• Improve vision
• Increase memory retention
• Improve quality of sleep
• Increase exercise performance
• Lower blood pressure
• Improve cholesterol profile
• Increase bone mass
• Quicken wound healing

Dr Ronald Klatz, a world-renowned expert on antiaging, is the founder and president of the American Academy of Antiaging Medicine. Coauthor of Death in the Locker Room, he is the medical director of Health.Net, an online medical information service. Dr Klatz lives in Chicago.

Carol Kahn is the author of Beyond the Helix and coauthor of Living Longer, Growing Younger and Crazy All the Time. A leading health and science writer, she lives in New York City.