Are you one of those who take a multivitamin in the hope of a longer life? It's completely in vain, according to a large new study.
The sale of vitamins is increasing, and in 2022, vitamins worth 927 million kronor were sold in Sweden, according to the industry organization Svensk egenvård.
But do they do any good? American researchers have tried to answer this in a study. They have compiled data on vitamin intake and life expectancy for nearly 400,000 healthy individuals who were followed for an average of 27 years.
No Longer Life
When they compared people who reported taking multivitamins with those who did not, they did not find that vitamin users lived longer. During the first 12 years of follow-up, there was even a small increased risk of death among those who took vitamins. However, this difference was not significant in later follow-up.
Susanne Rautiainen Lagerström, a doctor of medical science at the Karolinska Institute, has researched the benefits of dietary supplements and vitamins and is not surprised.
Many studies show similar results – that multivitamin use is not linked to reduced mortality.
The study, published in Jama Network Open, is an observational study where participants themselves answer questions about taking vitamins. This means that it is difficult to know for sure what types of vitamins the participants took and whether the associations can be explained by other factors.
But two large American randomized studies confirm the results. There is no convincing link between multivitamin use and prevention of cardiovascular disease and mortality, says Rautiainen Lagerström.
Can be Risky
Many multivitamin supplements contain low doses similar to those we get through food and pose no risk.
But in individual vitamin and mineral supplements, the doses can be much higher. One should be cautious with these because we do not know all potential harmful side effects, says Rautiainen Lagerström.
For example, beta-carotene supplements have been linked to an increased risk of lung cancer in smokers, and vitamin E supplements have been linked to an increased risk of cerebral hemorrhage in studies.
According to the National Food Agency, there is generally no need for extra vitamins unless you belong to a risk group.
Why do so many people want to take extra vitamin supplements?
The behavior around vitamin supplements is very interesting. We are probably influenced by marketing of various kinds and what is communicated in the media. Here, we all bear a responsibility, says Rautiainen Lagerström.
The National Food Agency's advice on who may need vitamin and mineral supplements in addition to food:
Vitamin D: All children up to two years of age. All over 75 years old. Children and adults who do not eat fish and vitamin D-enriched foods (including milk products, plant-based drinks, margarine, and fat blends). Children and adults who wear clothing that covers their face, arms, and legs or are not outdoors in the sun during the summer.
Folic acid: Women who may become pregnant.
Vitamin B12: Vegans who exclude all animal-based foods.
Source: National Food Agency