Multivitamins are the most commonly used supplements in the world. Their popularity increases rapidly.
Some people believe that multivitamins can improve health, compensate for poor eating habits, and reduce your risk of chronic diseases. However, is this true?
What are multivitamins?
Multivitamins are supplements that contain many different vitamins and minerals, sometimes alongside other ingredients. Their nutrient composition varies by brand and product as there’s no standard for what constitutes a multivitamin.
Available in many forms – tablets, capsules, gummies, powders, liquids – most of them should be taken once or twice a day. Multivitamins are available in pharmacies, large discount stores supermarkets, as well as online.
What they do.
Thirteen vitamins and at least 16 minerals are essential to your health. Many of them aid enzyme reactions in your body or function as catalyzing molecules or structural elements. Your body needs these nutrients for reproduction, maintenance, growth and regulation of several processes in the body.
Because dietary supplements are not regulated by the Food and Drug Administration (FDA), multivitamins may contain higher or lower levels of some nutrients than the label states. Or, they may not even provide all of the listed nutrients. So it’s highly recommended to purchase vitamins from a reputable manufacturer.
Keep in mind that the best quality nutrients in multivitamins may be derived from real foods.
Multivitamins and heart disease
Heart disease is the leading cause of death worldwide.
Many people believe that taking multivitamins can help prevent heart disease, but the evidence is mixed. Some studies suggest that multivitamins are correlated to a reduced risk of heart attacks and death, while others show no effect. For more than a decade, the Physicians’ Health Study II investigated the effects of daily multivitamin use in over 14,000 middle-aged, male doctors. It found no reductions in heart attacks, strokes or mortality. (https://www.ncbi.nlm.nih.gov/pubmed/23117775)
A more recent study revealed that among women — but not men — taking a multivitamin for at least 3 years was linked to a 35% lower risk of dying from heart disease.
Multivitamins and cancer
The evidence regarding multivitamin use and cancer risk is also mixed. There are studies suggesting no effect on cancer risk, while others link multivitamin use to increased cancer risk.
One review examined 5 randomized, controlled trials in 47,289 people. It found a 31% lower risk of cancer in men who took multivitamins but no effect in women (https://www.ncbi.nlm.nih.gov/pubmed/16880453)
Two observational studies, one including women and the other including men, tied long-term multivitamin use to a reduced risk of colon cancer (https://www.ncbi.nlm.nih.gov/pubmed/9758570)
The Physicians’ Health Study II noted that long-term, daily multivitamin use reduced the risk of cancer in men with no cancer history. But still with no effect on the risk of death during the study period (https://www.ncbi.nlm.nih.gov/pubmed/23162860)
Do multivitamins have any other health benefits?
Multivitamins have been studied for several other purposes, including brain function and eye health.
Brain function
Several studies have found that multivitamins can improve memory in older adults.
https://www.ncbi.nlm.nih.gov/pubmed/22939764
https://www.ncbi.nlm.nih.gov/pubmed/22711385
https://www.ncbi.nlm.nih.gov/pubmed/20110592
These supplements may also improve mood. Research reveals links not only between poor mood and nutrient deficiences but also between multivitamins and better mood or reduced depression symptoms.
https://www.ncbi.nlm.nih.gov/pubmed/10906550
https://www.ncbi.nlm.nih.gov/pubmed/10719135
https://www.ncbi.nlm.nih.gov/pubmed/16491668
https://www.ncbi.nlm.nih.gov/pubmed/23377209
https://www.ncbi.nlm.nih.gov/pubmed/22095836
https://www.ncbi.nlm.nih.gov/pubmed/10907676
Eye health
Age-related macular degeneration is a leading cause of blindness worldwide.
(https://www.ncbi.nlm.nih.gov/pubmed/22559899)
One study found that taking antioxidant vitamins and minerals may slow its progression. However, no evidence suggests that these compounds prevent the disease in the first place.
(https://www.ncbi.nlm.nih.gov/pubmed/22696317, https://www.ncbi.nlm.nih.gov/pubmed/24590236)
All the same, some evidence indicates that multivitamins may reduce your risk of cataracts, another very common eye disease.
https://www.ncbi.nlm.nih.gov/pubmed/24590236
