Demi Moore recently tweeted that she and Ashton Kutcher were doing the Master Cleanse. The fasting power couple joins a long list of Master Cleanse devotees including Naomi Campbell and Beyonce. Sales of cleanse products and laxatives hit almost $103.7 million in 2009, up 11 percent over the year before, according to Spins Inc., which tracks the natural product industry. Though cleanses and detoxes can cause rapid weight loss, most health experts agree you don’t need to detoxify your body. “The body, through the kidneys, is built to detox,” said Judy Penta, a nutritionist with Patients Medical in New York. Find out if any detoxes work, which don’t and which could be dangerous to your health.