Study: Too much multivitamins don't help at all

Excess pills are often harmful to health. A study found that taking daily multivitamins does not help people live longer and may even increase the risk of premature death. US researchers analyzed the medical records of nearly 400,000 adults who did not suffer from major long-term illnesses to see if multivitamins reduced their risk of death over the next two decades, writes The Guardian. Instead of living longer, people who took daily multivitamins were slightly more likely than those who did not take multivitamins to die during the study period, leading the researchers to state that "the use of multivitamins to improve longevity is not supported." . Almost half of UK adults take multivitamins or nutritional supplements once a week or more, part of a domestic market worth over half a billion pounds annually. The global supplement market is estimated at tens of billions of dollars each year. In the US, one-third of adults use multivitamins in hopes of preventing disease, but despite the popularity of multivitamins, researchers have questioned the health benefits and even warned that supplements may be harmful. While natural dietary sources of beta-carotene protect against cancer, for example, beta-carotene supplements may increase the risk of lung cancer and heart disease, suggesting that the supplements are missing important ingredients. At the same time, iron, which is added to many multivitamins, can lead to iron overload and increase the risk of cardiovascular disease, diabetes and dementia. For the latest paper, Dr. Erikka Loftfield and her colleagues at the National Cancer Institute in Maryland analyzed data from three major US health studies. All were launched in the 1990s and collected details on participants' daily multivitamin use. The records involved 390,124 generally healthy adults who were followed for more than 20 years. The researchers found no evidence that daily multivitamins reduced the risk of death and instead reported a 4% higher risk of death among users in the first years of follow-up. The higher risk of death may reflect the harm that multivitamins can cause or a tendency for people to start taking daily multivitamins when they develop a serious illness. Details are published in Jama Network. Dr. Neal Barnard, professor of medicine at George Washington University and co-author of a commentary published alongside the study, said vitamins are useful in specific cases. Historically, sailors have been saved from scurvy by vitamin C, while beta-carotene, vitamins C and E, and zinc appear to slow age-related macular degeneration, a condition that can lead to severe vision loss. It is also possible that vitamins are beneficial without reducing the risk of early death. A preliminary study conducted in 2022 found evidence that multivitamins could slow cognitive decline in old age, but more research is needed.