Medical research is beginning to suggest that vitamins have questionable health benefits.
One study found that vitamin C is ineffective for coldāprevention unless you’re exposed to extreme physical stress (read: ultramarathon runners and “soldiers during sub-Arctic winter exercises”).
The New York Times looks at this trend, noting that in some cases, vitamins may do more harm than good. However, there are always exceptions (B12 supplements for the elderly and folic acid for women of child-bearing age have proven health benefits) and caveats:
Despite a lack of evidence that vitamins actually work, consumers appear largely unwilling to give them up. Many readers of the Well blog say the problem is not the vitamin but poorly designed studies that use the wrong type of vitamin, setting the vitamin up to fail. Industry groups such as the Council for Responsible Nutrition also say the research isn’t well designed to detect benefits in healthy vitamin users.