"Most People Do Not Need Dietary Supplements"

It is almost impossible to avoid advertisements for dietary supplements on social media. They are heavily promoted and often presented as cure-alls. At the same time, platforms such as Instagram and TikTok have become major sources of misinformation. Hans Hauner, a nutrition specialist and Senior Professor at the Else Kröner Fresenius Center for Nutritional Medicine (EKFZ) at the Technical University of Munich (TUM), explains which supplements may be beneficial and when they can pose health risk

Which claims about dietary supplements do you keep seeing on social media even though the scientific evidence says otherwise?

The pattern is always the same: all kinds of dietary supplements are enthusiastically recommended even though there is no scientific evidence supporting the claimed benefits in most cases. For example, large-scale studies have shown that antioxidants such as vitamin C, vitamin E, and beta-carotene provide no benefit for heart health. In some cases, recommendations circulating on social media can even pose serious risks. Omega-3 or fish oil supplements, for example, may increase the risk of atrial fibrillation, while excessive vitamin E intake can raise the risk of heart failure.

Many people take vitamins and minerals. For which of these are the benefits scientifically well established?

Vitamin supplements are among the best-studied dietary supplements. Most studies show no health benefits, and some even suggest potential harms, making supplementation unnecessary in many cases. One exception is vitamin B₁₂ supplementation for people following vegan or vegetarian diets when blood tests indicate low levels. For minerals and trace elements, the evidence is often quite limited. We also know from nationwide dietary surveys in Germany that true deficiencies in vitamins and minerals affect only a small number of people, for example in the case of iodine, vitamin B₁₂, vitamin D during the winter months, or polyunsaturated fatty acids. Most people can obtain adequate amounts of these nutrients through a varied and health-promoting diet, without the need for supplements.

Artificial intelligence is opening a new chapter in social media misinformation. It is becoming increasingly difficult for users to tell whether posts, images, videos, or audio recordings were created with AI and whether the people shown are even real. Is the risk of AI-generated nutrition advice being underestimated?

These posts may look increasingly realistic, but they are certainly not a reliable source of guidance when it comes to dietary supplements. Millions of people around the world use AI, often without understanding how it works or what risks it entails. It is now widely recognized that AI systems can generate incorrect facts, references, or studies. Social media users should keep this in mind. For that reason, I would always recommend consulting qualified experts as well.

What questions should people ask themselves before buying a dietary supplement recommended by an influencer?

The first question should be: Could I actually be deficient in this nutrient? Genuine nutrient deficiencies affect only a small proportion of people in Germany and often only under specific circumstances. It is also important to consider whether someone belongs to a vulnerable group, for example because they have pre-existing medical conditions, are pregnant, or are of advanced age. In any case, people should ask whether independent scientific assessments of the ingredient are available and where they can be found. Anyone who is uncertain can seek information from the German Federal Institute for Risk Assessment (BfR), the Nutrition Radar , a platform for science-based nutrition communication supported by EKFZ, or the portal Klartext Nahrungsergänzung by the German Verbraucherzentrale. Qualified nutrition professionals can also provide individualized advice through nutrition counseling services.

Where do you see gaps in the regulation of health claims on social media?

On social media, misleading claims are often spread to persuade followers to buy these products. These posts are simply advertisements, usually from sponsored influencers. They make unproven claims and fail to disclose the risks. In Germany, registering a dietary supplement with the Federal Office of Consumer Protection and Food Safety is sufficient to place it on the market. The products themselves are not evaluated before approval. In my view, there should be a simple and rapid pre-market review process to determine whether products comply with food law requirements and whether manufacturers' and distributors' advertising claims are justified. In addition, social media influencers are legally required to disclose sponsorship arrangements, but violations are rarely prosecuted.

Which claim about dietary supplements do you wish people would stop repeating?

That is a difficult question because the list is rather long. What frustrates me most are the claims made for many plant extracts, such as ashwagandha products or high-dose beta-carotene supplements, whose benefits have not been proven and which can, in some cases, cause significant harm. But let us look at it from a more positive perspective. At the EKFZ for Nutritional Medicine, we would much rather see people sharing the message that a natural, varied diet is far more effective than isolated supplements. Nutritional medicine today fully recognizes that a Mediterranean diet can reduce the risk of cardiovascular disease by around 30 percent, an effect that dietary supplements could never achieve.

More generally, our diets have never been as nutritionally adequate as they are today, which means that most people simply do not need dietary supplements.