With over 100,000 supplements available in the US market, ranging from vitamins and minerals to botanicals and amino acids, consumption is surging. However, experts warn that a common misconception is that these products are entirely safe. Dr Pieter Cohen, an internist and associate professor at Harvard Medical School, emphasises that excessive amounts of nutrients can cause health problems, making it critical to use correct dosages of high-quality products.
Ideally, nutrients should come from food, but supplements may be necessary due to factors like poor access to nutritious foods or medication effects. Dr Denise Millstine, director of integrative medicine at the Mayo Clinic Arizona, notes that shopping for supplements can be 'dizzying' for consumers. For some nutrients, there is a recommended dietary allowance (RDA) and a tolerable upper intake level (UL), which is the maximum safe daily limit. Exceeding the UL can lead to health issues.
In the US, there is limited government oversight; the FDA does not approve supplements before sale. Dr Cohen advises that the only way to ensure label accuracy is to look for certification by non-profits like the National Sanitation Foundation (NSF) or United States Pharmacopeia (USP). It is also essential to consult a healthcare provider before starting any supplement, as interactions with medications or other supplements can cause adverse effects or reduce medication efficacy.
Supplements can also affect blood tests, leading to inaccurate results, according to Dr Fernando Carnavali, an associate professor at the Icahn School of Medicine at Mount Sinai. He stresses the importance of discussing supplement use with a physician, as research on interactions and harms evolves. Dr Millstine recommends using caution, sticking to studied doses, and avoiding dosing advice from sellers due to bias. She suggests using the National Center for Complementary and Integrative Health website or the USDA's nutrient calculator for reliable information.
