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Supplements are having a moment.

A 2022 survey of more than 3,100 U.S. adults indicated that 75 percent take some form of nutritional supplement. Of those consumers, 52 percent said they took a specialty supplement, like omega-3s, probiotics, or fiber.

Johna Burdeos, RD, a registered dietitian, says a myriad of factors have contributed to the popularity of supplements, vitamins, and minerals, including the pandemic and ease of purchasing via online retailers.

Still, supplements aren’t without their detractors. The industry isn’t regulated by the U.S. Food & Drug Administration (FDA).

Plus, you may wonder whether you need dietary supplements if you’re eating a well-balanced diet.

Here’s what the research and experts have to say about when it’s beneficial to add vitamins, minerals, and supplements to your diet, plus which ones to choose.

The subject is up for debate, even among experts.

“Supplements are not usually the only possible solution for most adults to achieve and maintain good health,” says Maddie Pasquariello, MS, RDN. “In fact, for many of those experiencing health problems, supplements are not usually the first line of defense that dieticians will turn to.”

Other lifestyle tweaks, like changes to diet and exercise recommendations, typically come first.

That said, supplements are recommended as a standard in some cases. In other cases, they may help fill in the gaps for nutrient deficiencies in the diet, says Stephanie Greunke, RD, a registered dietician and member of Needed‘s practitioner collective.

Common cases where providers will recommend taking vitamins, supplements, or minerals include:

  • pregnancy
  • lactation
  • infants receiving human milk or less than 32 oz. per day of formula
  • health improvement
  • special diets
  • deficiencies

Supplements may have their detractors, but some can be beneficial, particularly in specific circumstances.

Prenatal vitamin

The American College of Obstetricians and Gynecologists recommends people with uteruses should begin taking prenatal vitamins when they start trying to become pregnant and continue intake throughout pregnancy. Burdeos recommends starting three months in advance of your first attempt to become pregnant.

The CDC recommends taking prenatal vitamins with 400 mg of folic acid to protect against certain birth defects.

The ACOG recommends getting at least 27 milligrams of iron per day during pregnancy, something often found in prenatal vitamins.

Burdeos says folic acid combined with iron provides benefits for a fetus.

“Folic acid helps prevent neural tube defects, which are serious abnormalities in the baby’s brain and spinal cord,” Burdeos says. “Iron helps facilitate the transportation of oxygen throughout the body. Iron helps support the proper development of the baby and the placenta.”

Vitamin D

About 42 percent of people are vitamin D deficient, and Black people have the highest rates— 82 percent, according to a 2022 study.

The sun is a natural source of vitamin D, and egg yolks and fatty fish are quality food sources. Other than that, it’s slim pickings, according to the National Insitute of Health (NIH).

“It’s nearly impossible to get all the vitamin D you need from food alone,” Greunke says. “Oily fish, mushrooms, and fortified dairy provide vitamin D, but not in sufficient quantities to meet daily needs.”

Vitamin D deficiency is linked to multiple conditions, including:

Research suggests that taking vitamin D during pregnancy could reduce the risk of:

The NIH recommends that infants up to 12 months old take 10 mcg of vitamin D per day. Infant formula is fortified with vitamin D, so the CDC says that children younger than 12 months who are exclusively formula-fed likely don’t need a vitamin D supplement.

A 2015 study indicated that a lactating parent could take 6,400 IU of vitamin D per day to supply an adequate amount to the nursing infant through human milk.

The NIH advises that people ages 1 to 70 need 600 IU per day, and people over 70 should consume 800 IU per day. Since it’s challenging to get that from food, Greunke says a vitamin D supplement is worth it even past infancy.

Omega 3s

One of the most popular vitamins just might be Omega 3’s. They’re fatty acids naturally found in fish like salmon and nuts, such as walnuts.

Burdeos says that you may benefit from taking one if your diet is low on these items. Though omega 3’s are linked with good heart health, the National Center for Complementary and Integrative Health (NCCIH) says the data for that association is based on seafood intake.

However, the agency says it may help reduce triglycerides and soothe rheumatoid arthritis symptoms.

B12

B12 naturally occurs in animal products, and Burdeos says it’s important for:

  • red blood cell formation
  • DNA production
  • nerve function
  • cell metabolism.

An older study from 2022 indicates that B12 deficiency is higher in vegans than in vegetarians. Nearly two-thirds of pregnant people were also deficient. She says B12 supplementation is worth it for individuals who are deficient, particularly those who do not consume animal protein.

Iron

Iron is present in food like nuts and dark, leafy greens. According to the NIH, it helps:

  • carry oxygen from the lungs to the tissues
  • bolster muscle metabolism
  • support physical growth
  • aid in neurological development

Though Pasquariello typically recommends a food-first approach, people with iron deficiencies and those who are borderline anemic may benefit from iron supplementation.

Additionally, pregnant people should seek out a prenatal with iron to support fetal development. Always ask your doctor for the best option, as it’s possible to take too much iron, which in rare cases can lead to iron poisoning.

Magnesium

Magnesium is a naturally occurring mineral and the fourth-most abundant one in the body. Still, nearly half of the U.S. population doesn’t ingest enough magnesium, according to a 2018 study.

Greunke says that magnesium supplements can help.

Research indicates oral magnesium supplementation may help:

Some supplements, like probiotics, are all the rage. But experts and researchers say the data isn’t there to support the hype. You can hold off on trying these supplements.

Green powders

These powders look healthy and have promising buzzwords on labels.

“Most greens powders products claim to be filled with whole food sources of nutrients and pre- and probiotics,” Pasquariello says. “This is highly deceptive, as it tricks consumers into thinking they can then substitute greens powders for actual greens or green vegetables.”

Pasquariello says claims that greens powders boost energy, performance, and digestion are unfounded.

There’s not much research on them other than a small, 40-person study from 2009 that indicated that supplementing with a fruit and vegetable powder for 90 days might reduce blood pressure but not body weight.

Pasquariello suggests adding actual greens, specifically the leafy variety, to your diet instead.

Probiotics

Probiotics are one of the most popular supplements, but the NCCIH indicates the evidence to support probiotic supplements for issues like diarrhea and ulcerative colitis is not supported by data at this time.

Mega-anything

Some products will market themselves as having “mega-doses.” The jargon sounds great, but Burdeos says it’s not.

“Unless it is specified by your doctor, these kinds of supplements are a case of too much of a good thing,” she says.

She says the mega-doses can have long-term impacts.

“For example, too much vitamin D can lead to kidney problems, and too much vitamin C can cause digestive issues,” Burdeos says.

This applies to taking any supplement at all. If you’re getting the nutrients from diet alone, there’s no need to add any more of it to your diet through an oral tablet or powder.

Buffered creatine monohydrate

Greunke and research from 2017 indicate that creatine monohydrate can reduce injury and speed recovery. “Buffered” and “advanced” versions claim to be a step up.

“These formulas are more expensive and state that they’re better absorbed, but that hasn’t proven to be true,” Greunke says.

Since supplements are not held to the same standard as food, it can feel like the wild west out there. Experts share insights for navigating the vitamin and mineral aisle of the grocery store below.

Chelated vs. non-chelated

You may notice these terms on mineral bottles.

“Chelated means the mineral was altered in a way that improves absorption,” Greunke says. “This is done by combining the mineral with another molecule, like an amino acid or organic acid, to make it easier for the body to absorb.”

Examples include:

  • iron bisglycinate
  • zinc bisglycinate
  • chromium picolinate
  • and magnesium bisglycinate

“Non-chelated minerals, on the other hand, are unstable, and, as they aren’t bound to something else, they are attracting other molecules to bind to them, thus interfering more with absorption,” Burdeos says.

Research is mixed and often includes small sample sizes.

For example, a 2014 study of 15 people indicated that chelated zinc as zinc citrate and zinc gluconate was absorbed better than non-chelated zinc and might be beneficial for zinc deficiency and treating diarrhea.

A 2019 study suggested chelated magnesium glycerophosphate did a significantly better job of increasing blood magnesium levels than non-chelated magnesium oxide.

However, a 2014 study of postmenopausal people indicated that non-chelated calcium carbonate was absorbed more quickly and upped blood calcium levels better than calcium citrate.

Evaluating mineral sources

Greunke says food and water make up the majority of our mineral intake. They can also be found in:

  • trace mineral drops
  • salts
  • electrolyte products

“Thoughtful supplements take into consideration nutrient competition,” Greunke says. “For example, iron competes with other minerals for absorption, such as zinc, calcium, copper, and magnesium.”

Greunke suggests avoiding multivitamins with iron. Calcium and iron supplements can be taken a couple of hours apart. It’s also possible to take too much iron, so always talk to your doctor before adding it to your supplement regimen.

Some minerals act like electrolytes, including:

  • sodium
  • magnesium
  • potassium
  • calcium
  • chloride
  • phosphate

Greunke says electrolytes:

  • maintain fluid balance
  • keep your heart beating normally
  • aid in blood flow
  • regulates blood pressure
  • support bone health
  • influence your hormones
  • support adrenal health

Other important details when choosing supplements

The experts Healthline spoke with also recommended:

  • ensuring third-party testing, such as through U.S. Pharmacopeial Convention and Consumer Labs
  • avoiding artificial colors, flavors, and sweeteners
  • avoiding fillers like stearic acid, silicon dioxide, and titanium dioxide
  • choosing whatever works best for you when it comes to pills, chewables, gummies, or powders
  • selecting only the supplements that fit your medical and dietary needs
  • reading labels with a critical eye—if it sounds too good to be true, it probably is

How do you know if your supplement is actually working or whether should scale back? Experts share a few telltale signs.

Elimination

Much of what goes in comes out eventually.

“High doses of magnesium citrate and vitamin C can cause diarrhea, so if this is happening, you’ll want to reduce the amount you’re taking,” Greunke says. “Sometimes, high doses of B-vitamins can lead to bright yellow colored urine; however, this isn’t necessarily harmful.”

Your energy levels

Is the pep in your step the result of a supplement or a placebo effect?

“Some supplements like vitamin B12 can yield quick improvements in energy,” Greunke says. “Adrenal supplements can help individuals feel calmer and focused relatively quickly. If an individual is dehydrated or imbalanced in minerals, an electrolyte supplement can boost energy, physical performance, and improve blood pressure.”

Others may have more subtle or long-term effects.

OTC and in-office tests

Whether OTC or in-office testing is necessary depends on the reason you’re taking the supplements.

If it’s to lower blood sugar because of pre-diabetes or diabetes, at-home glucose monitoring and in-office bloodwork are important, Greunke says.

Pasquariello says medical professionals can also check the nutrient levels in your blood before you start taking a supplement and after consuming it for a specific period.

“If you’re just starting supplementation for the first time or using it to help improve certain symptoms, in-office tests can be helpful,” Pasquariello says. “If you’re experiencing side effects from a supplement, an in-office test can also be recommended.”

In general, Pasquariello says it’s always important to connect with your doctor about any supplements you’re taking to ensure they don’t interfere with any medications or treatments.

Want to learn more? Get the facts below

What vitamins/supplements should you take daily? What are the top 5?

This depends on your needs. People who are pregnant or trying to get pregnant should take a daily prenatal.

Vitamin D may also reduce the risk of pregnancy complications like gestational diabetes. Infants who aren’t formula-fed need daily vitamin D, or the lactating parent can supplement with vitamin D.

Other potentially important supplements include magnesium, iron, and omega 3s, but always talk to your doctor before you start supplementation, especially when it comes to iron.

How can you tell what supplements you should take?

Discuss this with your doctor or a dietician. The answer will depend on whether you are pregnant or lactating, age, diet, and health needs.

What vitamins/supplements do you need on a vegan or vegetarian diet?

Not all vegans and vegetarians require supplementation, but Pasquariello says B12 is the most common deficiency.

What vitamins and supplements do you need on a keto diet?

For those on the keto diet, Pasquariello suggests discussing vitamin D and calcium supplementation with your doctor.

What supplements do you need to build muscle?

Burdeos and Greunke say creatine monohydrate can help build muscle. The “buffered” kind is unnecessary and not supported by data.

What vitamins/supplements do you need to lose weight?

Most experts don’t believe vitamins or supplements are necessary for weight loss. Instead, work with a healthcare professional or dietician on meeting your goals through sustainable diet and lifestyle tweaks.

What supplements do you need if you’re a woman? For pregnancy?

Women don’t necessarily need special supplements, but experts say pregnant people should take prenatal vitamins with folate and iron. Ask your doctor for the best option for you.

It’s recommended that people begin taking prenatal vitamins three months before trying to become pregnant. Vitamin D supplementation during pregnancy may protect against pre-eclampsia, pre-term birth, and gestational diabetes.

Vitamins, minerals, and supplements are buzzy, but most people get enough nutrients from diet alone.

However, there are cases where supplementation is necessary, like during pregnancy or lactation.

It’s important to remember that the vitamin and supplement industry isn’t regulated by the FDA. Talk to your doctor about any supplements you’re considering to ensure they’re safe for you.


Beth Ann Mayer is a New York-based freelance writer and content strategist who specializes in health and parenting writing. Her work has been published in Parents, Shape, and Inside Lacrosse. She is a co-founder of digital content agency Lemonseed Creative and is a graduate of Syracuse University. You can connect with her on LinkedIn.