What vitamins should you take? Why experts say some answers to this are a 'big red flag.'

The last few years have seen a huge spike in health and wellness. The pandemic forced people to grapple with their own wellbeing, and they're subsequently searching for products that are easy to purchase and implement.

It's led to a dramatic rise in interest in vitamins and supplements. Dietary supplement sales in the U.S. increased by 50% between 2018 and 2020 — sales in 2020 amounted to more than $220 billion, according to a 2023 study published in the journal Nutrients.

And wellness influencers online often promote supplements as a one-stop-shop for fixing a certain ailment.

"Social media has significantly influenced people's interest in taking various vitamins, with influencers frequently promoting the new 'it' vitamins and making strong health claims that they attribute to their alleged supplement regimen," Washington, D.C.-based dietitian Caroline Thomason, R.D., tells USA TODAY. "This constant promotion creates trendy awareness but can also lead to misinformation, unnecessary supplementation and even harmful health consequences. Influencers' endorsements often prioritize trends, social engagement and popularity over scientific evidence ... and blanket statements that may not be suitable for everyone."

Vitamins and supplements can be a beneficial addition to a person's health and wellness routine — if used and obtained correctly. Some health experts worry that influencers online recommending a certain vitamin to achieve a certain health outcome can lead to people trying to fix things that aren't broken, or worse: actually causing new issues.

So how do you navigate the world of vitamins and supplements? Here's what health experts recommend.

'What vitamins should I take?'

Unfortunately, there's no one answer here. This question is best directed toward a primary care physician, who can first check your levels with a blood test. That medical professional, or a licensed dietitian, can then provide a personalized recommendation if you do have any vitamin deficiencies.

"There is not a one size fits all approach to vitamins, and if someone makes this seem true, this is a big red flag," Thomason says.

Unless your doctor says you're deficient in a certain vitamin, you're best off aiming to first get vital nutrients through your food intake, rather than supplements, notes the National Institutes of Health's Office of Dietary Supplements.

"If you don't have a deficiency, choosing to eat a variety of foods can help you meet your vitamin and mineral needs without needing to supplement your diet," Thomason adds.

More:Kourtney Kardashian is selling gummies for vaginal health. Experts are rolling their eyes.

What vitamins should not be taken daily?

There can be too much of a good thing, which is why health experts want consumers to be wary of regularly taking supplements that medical pros haven't told them they need.

Certain vitamins, like fat-soluble vitamins A, D, E, K, minerals like iron, and electrolytes like potassium and calcium, should not be taken regularly without consulting a dietitian or doctor due to risks of toxicity and adverse interactions. That's not to say they're inherently dangerous — these are all things your body needs — but they can be if you're not deficient to begin with.

Should you take daily vitamins?If so, which ones? What to know about benefits, marketing

"Depending on the vitamin and the dose, excessive intake can lead to serious health issues," Thomason says. In addition to the toxicity mentioned above, other risks could include liver damage, dangerously high calcium levels, bleeding and kidney stones. It's also important to confirm with a doctor that any supplements you add don't interact negatively with any medications you may be taking.