Are supplements good for you?

Dietary supplements are often seen as an easy way to improve health. Many people take them to boost energy, prevent illness or fill dietary gaps. Because they’re widely available and sometimes described as “natural,” people assume they’re always safe.

What are dietary supplements?

Dietary supplements are products that contain concentrated levels of nutrients, such as vitamins, minerals or other compounds like herbal extracts, amino acids and fatty acids.

They're generally used to complement diet when nutrient needs are not fully met through food alone. You can find these nutrients normally in food, but in supplements, they’re provided in higher amounts.

Supplements come in many forms, including tablets, capsules, powders and liquids. And they can be made from plant sources like garlic, animal sources such as fish oil or with synthetic ingredients like most vitamins.

Some examples of supplement groups include products such as multivitamins, single nutrient supplements, herbal products, protein powders and fatty acid supplements.

Unlike prescription medicines, supplements are widely available over the counter and can be easily purchased in pharmacies, supermarkets and online. In most countries, supplements aren't allowed to claim to diagnose, treat, cure or prevent diseases in the same way medicines do. For example, in the United States, supplements can't legally make these claims unless they are approved as drugs by the FDA.

10 reasons why people take supplements

People take supplements for different reasons including:

1. Complementing diet when nutrient needs are not fully met through food alone
2. Supporting specific dietary patterns, such as vegetarian or vegan diets
3. Supporting overall wellness during periods of stress or illness
4. Enhancing physical performance and recovery
5. Supporting energy levels and reducing fatigue
6. Supporting general health and wellbeing
7. Helping manage nutrient deficiencies
8. Supporting bone and immune health
9. Supporting heart health
10. Improving sleep

Situations where supplements are needed most

Supplements can be beneficial for individuals with specific nutrient deficiencies or during specific life stages when nutrient needs are higher. In these situations, supplements address the specific nutrient gap. They're not a general addition to the diet.

For instance, folic acid is often recommended during pregnancy because it helps support the early development of the baby’s brain and spine, and reduces the risk of birth defects that affect these areas. This is important in the early weeks of pregnancy, when these parts of the body are forming very quickly, often before someone even knows they are pregnant. Without enough folic acid, the risk of these problems can increase.

Vitamin D supplements may also be needed when sun exposure is limited, especially in places with long winters. Your body makes vitamin D when your skin is exposed to sunlight, so when you don’t get enough sun, the levels can drop. Vitamin D helps keep your bones strong and supports your immune system. When levels stay low over time, it can increase the risk of weak bones and other health problems.

People who follow restrictive diets, such as limited animal products, may also need certain nutrients from supplements. For example, vitamin B12 supplements are commonly needed when animal products are limited since it’s mostly found in foods like meat, fish, eggs, and dairy. Vitamin B12 is important for nerve function and the formation of red blood cells. Low levels over time can lead to fatigue, weakness and other health problems.

Are supplements always safe?

Supplements can be helpful when there’s a clear need. But in practice, many people use supplements without much guidance, and they’re not always discussed during routine healthcare visits.

Because supplements are easy to find and sometimes described as “natural,” it can be easy to assume they’re always “safe”. Taking more than the recommended dose of certain vitamins and minerals can lead to serious health problems.

For example, too much Vitamin A may cause headaches, dizziness or even liver damage over time. High amounts of vitamin D over time can also increase calcium levels in the body, which may contribute to kidney problems such as kidney stones.

There is also the risk of interactions. Some supplements can interfere with medications or with each other. This can change how well a medication works or increase the risk of side effects.

For example, herbal supplements such as garlic and ginkgo biloba may increase bleeding risk when taken with blood thinners such as Warfarin.

Some medications also reduce the effectiveness of supplements. Taking iron supplements together with antacids can reduce how much iron the body absorbs.

Another common problem is that supplements can give a false sense of security. When people focus on taking pills or powders, they might forget about the importance of having a healthy overall diet.

Someone who regularly uses protein powders could pay less attention to including protein-rich whole foods in their diet. This can make it easy to overlook the importance of nutrient-rich and balanced meals, and the variety of nutrients found in whole foods.

Are supplements drugs?

No. Dietary supplements are not approved by regulatory authorities for safety and effectiveness like drugs are. Instead, companies are responsible for ensuring that their products meet safety standards. In other words, the supplement producers are trusted to keep themselves in check.

What's written on supplement label may not fully reflect what’s inside. Products may contain more or less of a nutrient than expected or include ingredients that are not listed at all.

In one widely reported case, people took a supplement believing it contained a safe amount of selenium. It was later found to contain about 200 times more than what was listed on the label. Many developed symptoms such as fatigue, hair loss and digestive problems.

Marketing can make supplements sound more effective than they are. You often see claims about boosting immunity, increasing energy or helping with weight loss. But these claims are not always supported by evidence. Because of this, it can be very hard to figure out which products to trust.

Are supplements even necessary?

Not everyone needs to take supplements regularly. A balanced diet can provide the nutrients your body needs.

For most people, eating a variety of whole and nutritious foods is enough to meet daily nutrient needs. Taking supplements doesn’t necessarily offer additional benefits.

Some people turn to supplements when they feel tired or want to improve their health. However, these concerns are often better addressed by looking at overall eating habits, sleep and daily routines.

This doesn't mean supplements are not useful. It only means they’re most helpful when there’s a clear reason to use them rather than as a routine habit.

Dietary supplements are not a shortcut to better health

They’re best as a support for a nutritious diet. It’s useful to look beyond marketing claims and consider questions such as whether the supplement is needed, whether the dose is appropriate and whether the product is reliable. If you're unsure, speaking with a qualified health professional can help guide your decision. For a practical way to think through these choices, you can explore the 4 questions to ask before buying any supplements.