More than half of Americans are taking them , fueling a $ 30 billion industry . David Seres : But supplements are not the amazing panacea that we are led to believe . He says vitamin C and selenium supplements , for example , may not be safe for humans . Seres : We need to reassess regulation of dietary supplements and educate the public .
More than half of Americans are taking supplements , fueling a $ 30 billion industry . David Seres : But supplements are not the amazing panacea that we are led to believe . He says vitamin E and selenium supplements , for example , may not be safe for men . Seres : We need to reassess regulation of dietary supplements and educate the public .