Final answer:
Manufacturers and distributors of dietary supplements do not have to provide evidence of their product's safety or effectiveness to the FDA unless a new dietary ingredient is added, due to the DSHEA of 1994. Supplement claims must include disclaimers and products are regulated after-market if proven hazardous. The FDA regulates supplements differently from medicines, which require extensive testing and approval.
Step-by-step explanation:
Manufacturers or distributors of dietary supplements are governed by the Dietary Supplement Health and Education Act (DSHEA) of 1994, which stipulates that they do not need to provide the U.S. Food and Drug Administration (FDA) with evidence to substantiate the safety or effectiveness of their products unless a new dietary ingredient is added. The FDA regulates supplements more like food rather than pharmaceuticals, meaning that supplement companies are responsible for determining the safety of their supplements. However, they must ensure that the product meets the FDA's Good Manufacturing Standards. Claims made on supplement labels must include a disclaimer if they suggest that the supplement can diagnose, treat, cure, or prevent any disease, as these claims are not approved by the FDA.
Thus, supplement claims and evidence backing them up are mostly the responsibility of the manufacturers. Dietary supplements are often removed from the market only after the FDA has proven them to be hazardous. This framework starkly contrasts with the regulation of medicines, which requires extensive testing and approval by the FDA before they can be sold in pharmacies, as part of ensuring public safety and efficacy of drugs. Consequently, consumers relying on dietary supplements must exercise caution and consider questions about effectiveness, interactions with food or medication, necessity for health, affordability, and safety.