Understanding multivitamins: What they can and can’t do

The allure of promises such as glowing skin, better sleep, and a longer life can be hard to resist, especially when endorsed by celebrities and influencers. But before you reach for that bottle of vitamin gummies or patches, let’s delve into the science to see who truly benefits from these supplements.

The multivitamin market has exploded in recent years, with products being marketed in more palatable forms like powders, liquids, and gummies. The Kardashian-Jenner clan and Gwyneth Paltrow’s Goop are just a few of the high-profile names that have jumped on the bandwagon, promoting these supplements as the elixir of youth and health. On social media platforms, influencers tout the benefits of multivitamin gummies and patches, claiming they can do everything from boosting your energy to improving your complexion.

However, experts are urging caution. According to Barbara Mintzes, a professor of evidence-based pharmaceutical policy at the University of Sydney, a healthy individual with access to a balanced diet, particularly one rich in whole foods, generally does not need vitamin supplements. Prof Nial Wheate, a medicines researcher at Macquarie University, echoes this sentiment, suggesting that for most people, these supplements offer no real benefit and can be a waste of money.

The body of evidence from numerous meta-analyses supports these claims, indicating that multivitamins do not significantly improve heart health, reduce the risk of certain cancers, or extend lifespan. In fact, an Australian meta-analysis focusing on older adults found no difference in mortality risk for those taking multivitamins.

Clare Collins, a professor of nutrition and dietetics at the University of Newcastle, points out that many vitamins are water-soluble, meaning that once your body’s stores are saturated, the excess is simply excreted in urine. She suggests that the popularity of multivitamins may stem from people using them as an insurance policy because they suspect their diets are not as healthy as they should be. However, multivitamins cannot replace the dietary fibers, phytonutrients, and other essential components found naturally in a variety of foods.

Moreover, there are risks associated with taking certain supplements, particularly in high doses. Fat-soluble vitamins, such as vitamin A, can accumulate in the liver and become toxic if overconsumed. While this is unlikely to happen with multivitamins, the danger arises when individuals take megadoses of isolated vitamins.

When it comes to supplements claiming to benefit hair, skin, and nails, Dr. Helen Macpherson, a senior research fellow at Deakin University, advises skepticism. Many of these products contain ingredients like biotin in concentrations too low to have any physiological benefit. Furthermore, high doses of biotin can interfere with lab tests, potentially leading to false medical diagnoses.

In Australia, most multivitamins are regulated as ‘listed’ medicines by the Therapeutic Goods Administration, which means they are subject to less stringent rules than ‘registered’ medicines, such as prescription drugs. Companies selling these vitamins are only required to prove their safety, not their efficacy.

So, who can actually benefit from vitamin supplements? There are certain groups for whom supplements can be crucial. Vegans may need vitamin B12 supplements, as this vitamin is typically obtained from animal sources. Iron supplements can be necessary for those with iron-deficiency anemia, and calcium and vitamin D may be recommended for postmenopausal women at risk of osteoporosis. Pregnant women are advised to take folate, iodine, and vitamin D for fetal development, and individuals with darker skin or limited sun exposure may require vitamin D supplements. Additionally, for those with age-related macular degeneration, a combination of zinc and antioxidants known as AREDS2 supplements can help reduce the risk of the condition worsening.

Ultimately, the decision to take vitamin supplements should be made in consultation with a healthcare provider, who can help identify any specific nutrient deficiencies. A multivitamin is unlikely to be sufficient in these cases, and targeted supplementation may be necessary.

Have you had experiences with multivitamins or other supplements? Do you feel they’ve made a difference in your health, or have you found them to be unnecessary? Share your stories and insights in the comments below!

Also read: I’m iron deficient. Which supplements will work best for me and how should I take them?