Final answer:
The disclaimer on supplements stating they have not been evaluated by the FDA is required because supplements are not subject to the same approval process as pharmaceuticals before they can be sold. The FDA monitors supplements for safety post-market, and the DSHEA of 1994 shifted the responsibility for supplement safety to manufacturers.
Step-by-step explanation:
The disclaimer "this statement has not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease" is commonly found on dietary supplements because the U.S. Food and Drug Administration (FDA) regulates supplements differently from pharmaceuticals. Supplements are treated more like foods and must adhere to Good Manufacturing Practices. However, they are not required to be proven safe or effective before being marketed, unless they contain new dietary ingredients. The FDA's Postmarket Safety Surveillance program only removes supplements from the market after they have been proven hazardous. This regulatory landscape allows for supplements to make certain health claims without FDA approval, but they must carry a disclaimer to inform consumers that these claims are not verified by the FDA. The Dietary Supplement Health and Education Act (DSHEA) of 1994 further emphasized manufacturers' responsibility for the safety of their products, reducing the need for FDA approval prior to distribution.
When considering supplementation, it is crucial to question the necessity, safety, and evidence backing the supplement's claims. This is because the scientific community may not fully understand how a supplement works, and the supplement could have interactions with food or medication, or contain harmful substances. Hence, buyer beware (caveat emptor) is an important principle in the context of dietary supplements.