Marily Oppezzo, a dietitian and researcher at Stanford University, said she was occasionally shocked by the number of supplements her clients take. A “stack” in the morning and another at night, she said — sometimes 20 different types or more.
In a 2024 survey of more than 3,000 American adults, over half of the respondents reported using supplements regularly. And Oppezzo said that many of her clients started taking them after being influenced by podcast hosts or social media.
“There can be good reasons to use supplements,” Oppezzo said, “if you have a nutrient deficiency, for example, or are pregnant. But many of the supplements people take are unnecessary, and can even be risky.”
Supplements can contain contaminants or excessive levels of nutrients, or interact with certain over-the-counter or prescription medications, opined Dr JoAnn Manson, a professor of medicine at Harvard Medical School. “It’s usually safer and healthier to get important nutrients from your diet,” Manson added. “And in many cases, you’re probably already doing so without trying.”
Here are 10 of the most popular dietary supplements that people take, and what to eat instead to get the same benefits.
“Many people take multivitamins as a ‘backstop’ just in case they don’t get enough vitamins and minerals from their diet,” said Wesley McWhorter, a dietitian in Houston.
And while it’s true that some people may benefit from taking multivitamins — including older adults, those on restrictive diets and those who have trouble absorbing nutrients (like those with celiac disease or Crohn’s disease) — most people can get all of the nutrients they need by following a balanced diet, Manson said. “This includes eating plenty of fruits and vegetables, legumes, nuts and seeds, whole grains, dairy products and healthy sources of protein,” she said.
“The more colourful the fruits and vegetables you eat, the wider the range of nutrients you’ll get, said Ethan Balk,” a clinical associate professor of nutrition at New York University.
Magnesium supplements have been touted for insomnia, migraine headaches, depression, constipation and more.
“There is some, albeit limited, evidence to back up some of these claims, experts say. But it’s worth seeing if you can get the same benefits from eating magnesium-rich foods first,” said Abeer Bader, a dietitian at Massachusetts General Hospital.
Around half of adults in the US don’t consume the recommended 310-420 milligrams of magnesium per day. Try adding an ounce of pumpkin seeds (156 milligrams) or an ounce of almonds (77 milligrams) to yogurt or oatmeal. Or incorporate a half-cup of cooked spinach (98 milligrams), black beans (60 milligrams) or quinoa (55 milligrams) into soups or stews.
Research suggests that people who regularly eat fish — which is rich in omega-3 fatty acids — have better heart health and lower rates of dementia and depression
Probiotic supplements contain certain strains of ‘good’ bacteria that are supposed to support a healthy gut microbiome, and prebiotics are substances that feed those good microbes to help them grow.
“We don’t have good evidence that these supplements help most people,” Oppezzo said. “So unless your doctor recommends them, skip it.”
To support a healthy microbiome (and get essential nutrients in the process), Oppezzo recommended eating fermented foods such as kimchi, sauerkraut, yogurt, kefir and miso. “And to ensure your gut microbes are well fed, eat plenty of fibre from plant-based whole foods,” McWhorter said.
Research suggests that people who regularly eat fish — which is rich in omega-3 fatty acids — have better heart health and lower rates of dementia and depression.
Large clinical trials have generally failed to find the same benefits of taking omega-3 (or fish oil) supplements, though one trial suggested a reduced risk of cardiovascular events for people who did not routinely eat much fish.
“If you want to get more omega-3s from your diet, the best sources are fatty fish like salmon, herring, sardines, mackerel and trout,” said Whitney Linsenmeyer, an assistant professor of nutrition and dietetics at Saint Louis University. “Aim for two servings per week. Flax seeds, chia seeds, walnuts, canola oil and soybean oil are also good sources.”
Many people take vitamin C supplements to strengthen their immune systems or ward off viral infections. And while it’s true that vitamin C plays important roles in the body, including promoting wound healing and protecting against cell damage, the research supporting the benefits of vitamin C supplements is limited.
Federal guidelines recommend at least 75 milligrams of vitamin C per day for most women and at least 90 milligrams per day for most men. “It’s easy to get that much from your diet,” Linsenmeyer said. “Just one orange, two kiwis, a cup of cooked broccoli or a half-cup of cooked red bell pepper supplies the daily amount.”
Collagen supplements claim to reduce wrinkles, minimise joint pain and strengthen hair and nails. But the evidence for such benefits is mixed and limited, said Emma Laing, the director of dietetics at the University of Georgia.
“Instead, support the natural synthesis of collagen in your body by consuming enough protein, vitamin C, copper and zinc — which you can do by following a balanced diet,” Laing said. “To protect the collagen you already have, limit sun and alcohol exposure, avoid tobacco, stay hydrated and get regular exercise.”
If you have a vitamin B12 deficiency or are at risk of developing one, your doctor may suggest that you take a B12 supplement.
“Those at risk include older adults, vegans and vegetarians, people with certain autoimmune conditions, and those who take some medications (like metformin or proton pump inhibitors),” said Wren Cahoon, a dietitian at UCHealth University of Colorado Hospital.
For most other adults, it’s not hard to get the recommended 2.4 micrograms per day from your diet. “Fish, red meat, poultry, eggs and dairy products are all good sources,” Cahoon said. “In fact, just one serving of salmon, tuna or beef can provide around the daily amount.”
Many breakfast cereals and plant-based milks are also often fortified with vitamin B12.
Those trying to lose weight or gain muscle may think that protein powder is a must-have. But unless you struggle to consume enough — which older adults or people recovering from hospitalisation or surgery often do — most people who follow a balanced diet get enough protein, McWhorter said.
To ensure you hit your daily target, Linsenmeyer recommended including a protein-rich food at every meal, like Greek yogurt, eggs, legumes or a lean protein source like fish, chicken or turkey.
The majority of people don’t get the recommended 21 to 38 grams of fibre per day. And fibre supplements — sold as pills, powders and gummies — are positioned to fill that gap.
“Getting fibre from whole foods, such as legumes, nuts, whole grains, fruits and vegetables, is preferable since they can provide not only fibre but also other healthful nutrients such as vitamins, minerals, protein and healthy fats,” Bader said.
“If you can’t get enough fibre from your diet alone, it’s fine to take a supplement,” said Dr Kyle Staller, a gastroenterologist at Massachusetts General Hospital. He recommends psyllium fibre, a soluble fibre that forms a gel in water. “Unlike some other fibre supplements, it can improve common digestive issues such as constipation, diarrhoea and abdominal pain,” added.
These supplements usually contain a long list of powdered fruits, vegetables, herbs and seeds, and many contain added vitamins, minerals, prebiotics and probiotics. They’re advertised as a convenient way to make up for whatever might be missing in your diet, especially fruits and vegetables.
But Oppezzo said that greens powders were little more than “glorified multivitamins.” “They definitely don’t replace the act of eating your actual vegetables,” McWhorter said.
Greens powders can also be expensive, with some running around $100 for a one-month supply. “You’re better off spending that money on fresh or frozen fruits and vegetables,” Balk said. “The real food is going to work just as great, if not better.”
The New York Times