Do you really need supplements? What a dietitian wants you to know.

Dietary supplements are a growing industry, with more than 3 in 5 adults in the US taking at least one daily supplement.(1)

But with shelves of pills, powders, and gummies for every nutrient from A to Z, how do you know what’s right for you? We asked a Rightway dietitian for her thoughts.

What are supplements?

Dietary supplements are over-the-counter products that provide concentrated forms of vitamins, minerals, and other ingredients. They’re designed to add to or supplement your diet to help you meet your daily nutritional needs.(2)

Common supplements include:

• Vitamins like multivitamins, vitamin C, and vitamin D.
• Fatty acids like fish oil.
• Minerals like calcium, magnesium, and iron.
• Nutrients like protein and fiber.
• Probiotics and prebiotics.

Supplements can be beneficial for your health and overall wellness, but they can also come with risks and may not be as effective as advertised.(3)

Does everyone need to take supplements?

“Take your vitamins” has become somewhat of a cliché for taking care of your health, but in reality, there’s no evidence that the average healthy adult needs any supplements, even a multivitamin.

In research on the effects of multivitamins, multiple studies found that they did not reduce the rate of heart disease, cancer, or mental decline, and did not increase life expectancy.(4) If you’re eating a nutritious diet of fruits, vegetables, protein, and carbohydrates, most people can get all their essential nutrients without turning to the supplement aisle.

However, that doesn’t mean there’s never a place for supplements.

Who could benefit from supplements?

People with diagnosed deficiencies, limited diets, or dietary restrictions may benefit from adding a supplement to their routine.

Supplements can also be important for people with specific conditions, such as pregnancy. For pregnant people, taking a prenatal vitamin or folic acid supplement is highly recommended to ensure they have all the nutrients they need to support a healthy pregnancy and prevent birth defects.(5)

Common supplements and who they could be useful for.

• Iron: Your body needs iron for healthy red blood cell functioning, which is why people who lose blood often, such as those who menstruate or frequent blood donors, may benefit from taking a supplement. Iron supplements are also important for people with diagnosed anemia or iron deficiency.(6)
• Vitamin B12: This vitamin is typically found in animal products, so doctors may recommend vegans and vegetarians take a supplement to maintain healthy brain and nerve function. Older adults may also benefit from vitamin B12 since it can be harder for your body to absorb it as you age.(7)
• Calcium: Calcium is often found in dairy products, so people with lactose intolerance, milk allergies, and vegans can use a supplement to fill the gap. Calcium supplements can also be helpful for postmenopausal people and older adults whose ability to absorb calcium has declined.(8)

Supplement quality matters—and varies.

Not all supplements are created equal. In the US, supplements are not tested by the FDA to confirm their safety and effectiveness.(9) That means supplement brands have to employ a third party to test their products and verify the claims they make. But not all brands take this step.

Before buying a supplement, make sure it's gone through verifiable third-party testing. You can check for this by looking for a seal from one of the testing sites on supplement labels, or by searching for the supplement on their websites. Common third-party testing sites include US Pharmacopeia,(10)NSF International,(11) and Consumer Lab.(12)

Tips to use supplements safely and effectively.

1. Try to get your nutrients from food first.

Eating a balanced, colorful diet gives you a wide range of vitamins and minerals, along with added nutrients like dietary fiber, which supplements often lack. It can also be easier for your body to absorb nutrients through food, making it more effective for your overall health.(13)

Instead, use supplements to fill any dietary gaps. Start by looking at your diet, identifying any nutrients you may be missing, and seeing what foods can fill the gap before you turn to supplements. For instance:

• Fiber: You can increase your fiber intake by eating more fiber-rich foods like whole grains, fruits, vegetables with the skin on, beans, and lentils.(14)
• Protein: If you’re low on protein, try finding ways to add protein into what you typically eat, like blending cottage cheese, beans, nuts, or eggs in sauces, or adding nut butters to oatmeal, yogurt, or bread.(15)
• Vitamin D: Vitamin D isn’t only absorbed through the sun. You can meet your vitamin D requirements by eating fatty fish, egg yolks, or fortified milk and cereal.(16)
• Magnesium: There are many magnesium-rich foods you can add to your diet, like spinach, broccoli, legumes, seeds, and whole-wheat bread.(17)

If certain foods aren’t realistic for you to eat regularly, a supplement may be right for you. If you don’t like fish and can’t see yourself incorporating it into your diet often, for example, you may benefit from taking a fish oil supplement to get the omega-3s you need to support your health.(18)

2. Always consult with your healthcare providers.

Before taking any dietary supplements, talk with a healthcare professional to learn more about the benefits and risks for your specific body and health needs.

Many supplements can impact the effectiveness of other medications, bring risks for underlying conditions, or have negative effects when taking too much.(19) Your doctor can help you stay safe and decide which supplement, if any, is right for you.

3. Check for interactions.

Just like prescriptions can have harmful interactions with other medications, so can supplements.(20) When considering any supplement, it’s important to check its interactions against your prescriptions, over-the-counter medications, and other supplements.

For example, taking calcium and iron together can reduce the effectiveness of your iron supplement.(21) People on blood-thinning medications should also generally avoid vitamin K, which can reduce these medications’ ability to prevent dangerous blood clots.(22)

4. Be aware of the dosage.

More is not always better when it comes to supplements. In fact, some vitamins have high risks associated with consuming more than recommended.(23) For example:

• Vitamin B6: Excessive amounts can cause nerve damage, neurologic issues, and skin lesions.(24)
• Vitamin A: Even moderately high amounts can cause headaches, nausea, and increase the risk of bone fractures, liver damage, and birth defects for pregnant people.(25)
• Vitamin D: Exceeding recommended doses can cause nausea, muscle weakness, brain fog, kidney damage, and, in extreme cases, death.(26)
• Iron: Too much iron can become toxic and damage the heart, liver, and pancreas, leading to heart flutters, joint pain, fatigue, and abdominal pain.(27)

Even vitamins and minerals that don’t cause extreme side effects from overconsumption are not more beneficial in higher doses.

Your body stops being able to absorb some vitamins after a certain level, which means if a supplement has a higher dose than your body can use, the remainder of those vitamins are just excreted.(28) Make sure to confirm what your safe daily intake level is before taking any supplement.(29)

5. Take supplements to boost absorption.

Some supplements are absorbed best with certain foods or alongside other supplements, while others are best absorbed alone.

For example, iron supplements are best absorbed on an empty stomach, so try taking them in the morning for maximum effectiveness. Vitamin C also enhances absorption of iron, so making sure you’re getting enough vitamin C throughout the day is also important to make the most of your iron supplement.(30)

Your healthcare provider can help you understand how supplements work together and with your body to achieve the best results.

The bottom line.

There’s little evidence that the average healthy adult benefits from taking any supplements. In general, it’s best to try to get your nutrients from food first. But, if you are interested in taking supplements or have specific needs or conditions that require them, make sure they’re third-party tested and consult with your healthcare providers.

Remember, you can always reach out to Rightway if you have questions or need support. We’re here to help you on your journey to better health.

Download the Rightway app and connect with a healthcare expert today if you have any questions or need support.

Sources:

1 Zhao, et al. (2025). Trends in dietary supplement use among U.S. adults between 2011 and 2023. European Journal of Nutrition.

2 Food and Drug Administration. (2022). FDA 101: Dietary supplements.

3 Starr. (2015). Too little too late: Ineffective regulation of dietary supplements in the United States. American Journal of Public Health.

4 National Institutes of Health Office of Dietary Supplements. (2024). Multivitamin/mineral supplements facts sheet for health professionals.

5 National Institutes of Health Office of Dietary Supplements. (2025). Dietary supplements and life stages: Pregnancy.

6 National Institutes of Health Office of Dietary Supplements. (2023). Iron fact sheet for consumers.

7 National Institutes of Health Office of Dietary Supplements. (2025). Vitamin B12 fact sheet for consumers.

8 National Institutes of Health Office of Dietary Supplements. (2023). Calcium fact sheet for consumers.

9 National Center for Complementary and Integrative Health. (2019). Using dietary supplements wisely.

10 USP. (2026). USP verified products.

11 NSF. (2026). Certified products and systems.

12 Consumer Lab. (2026). Product reviews.

13 American Heart Association. (2023). Dietary supplements: Hype or help for good health.

14 Harvard Health Publishing. (2025). Best source of vitamins? Your plate, not your medicine cabinet.

15 National Cancer Institute. (2024). Ways to add protein to your diet.

16 National Institutes of Health Office of Dietary Supplements. (2025). Vitamin D fact sheet for health professionals.

17 National Institutes of Health Office of Dietary Supplements. (2026). Magnesium fact sheet for health professionals.

18 National Center for Complementary and Integrative Health. (2024). Omega-3 supplements: What you need to know.

19 Cleveland Clinic. (2025). Why your doctor needs to know what supplements you’re taking.

20 Food and Drug Administration. (2022). Mixing medications and dietary supplements can endanger your health.

21 Abioye et al. (2021). Calcium intake and iron status in human studies: A systematic review and dose-response meta-analysis of randomized trials and crossover studies. The Journal of Nutrition.

22 Cleveland Clinic. (2024). What to avoid when taking a blood thinner.

23 Stanford Medicine. (2025). In search of clarity on supplements: Five myths worth busting.

24 Mayo Clinic. (2025). Vitamin B-6.

25 Borgan, Khan, and Makin. (2022). Hypercalcemia and vitamin A: A vitamin to keep in mind. Cleveland Clinic Journal of Medicine.

26 Mayo Clinic. (2025). Vitamin A.

27 Cleveland Clinic. (2025)Hemochromatosis (Iron overload).

28 Lykstad and Sharma. (2023). Biochemistry, water soluble vitamins. National Library of Medicine.

29 US Department of Agriculture. (2026). DRI Calculator for healthcare professionals.

30 ConsumerLabs. (2024). How to take vitamins properly.