Myth: You can use either hot or cold tap water for cooking.

Reality: There’s a reason your mother told you to fill the pasta pot with cold water: Hot water can leach lead out of pipes, and “there’s a possibility that lead is somewhere along the plumbing circuit in any home,” says Michael Shannon, M.D., a professor of pediatrics at Harvard Medical School. According to the EPA, houses built before 1986 are the most likely to have lead pipes, fixtures, fittings, and solder. But even plumbing legally considered lead-free may contain up to 8 percent lead. While copper pipes replaced lead ones decades ago, fusing pipes with lead was legal until 1991.

Get in the habit of using cold water for cooking, says Shannon. To have your water tested by a certified laboratory, call your local water authority or go to www.realsimple.com/watertesting for information on home test kits.

Bottom Line: Use cold water for cooking to cut your risk of exposure to lead.