megadoses

Megadoses are intakes of nutrients or other substances far beyond amounts needed for normal health. In nutrition and medicine, the term usually refers to vitamins or minerals taken well above recommended dietary allowances or upper intake levels. There is no universal threshold; megadoses are often described as multiple times the RDA or UL, sometimes reaching grams per day for certain vitamins.

Rationale and uses: Some people take megadoses to correct perceived deficiencies, boost purported benefits, or follow certain alternative regimens. Megavitamin therapy has a history in popular health movements, but strong evidence of benefit is limited. In some medical contexts, high-dose regimens are used under physician supervision, though these practices remain controversial.

Risks: Megadoses can cause toxicity and adverse effects. Fat-soluble vitamins (A, D, E, K) accumulate and can cause serious toxicity with long-term excess. Water-soluble vitamins may cause GI upset, kidney stones, or neuropathy at very high intakes, and minerals can disrupt metabolism or damage organs. The quality and labeling of supplements vary, and regulatory oversight is often limited.

Regulation and guidance: Medical advice and evidence are essential; megadoses are generally not recommended for healthy individuals outside of supervised settings. Researchers emphasize that for most nutrients, benefits do not outweigh risks at high doses. See also megavitamin therapy and hypervitaminosis.