Now that we’re seeing magnesium capsules and collagen powder cram the shelves at clothing stores and mainstream beauty counters, it’s safe to say that supplements—a $37 billion industry and growing—are our new normal.

We know that supplements can step in when our diets fall short (though it goes without saying that they’re not a replacement for a healthy diet), and many have been backed thoroughly by scientific research: Calcium and vitamin D help keep bones strong, DHA omega-3 fatty acid plays a role in supporting brain, eye and joint health, and folic acid decreases the risk of certain birth defects. But it’s also critical to be aware of any other kinds of effects a supplement might have on your body.

Case in point: Did you know that vitamin B7—or biotin, which is commonly used to support healthy skin, hair, and nails—may skew certain lab test results when taken in very high doses? That’s why it’s crucial to research any supplements, its proper dose, and its effect on your body before you stock your cabinet. And the first place to start is your healthcare provider.

Physicians, pharmacists, and dieticians should always be kept in the loop when you’re thinking about incorporating any new supplementto your routine, so together you can discuss what’s best for your overall health. According to a recent survey that polled 500 American adults, over 60% of millennials believe that they don’t need to tell their doctor when they’re taking a new vitamin or supplement.

And what’s more—this is a big one—nearly 40% of people who take both prescription medication and supplements don’t know that incorporating vitamins and supplements can actually impact the effectiveness (good or bad) of their existing RXes.

Supplements can interact with existing medications.

Since supplements are full of highly active ingredients, certain supplements, when ingested, may change absorption, metabolism, or excretion of a prescription medication you might already be taking. This is huge because it means your medication’s potency may be affected, so you may be getting too much or too little of the medicine you need.

Thankfully, personalized nutrition program Persona (name change: you may remember them as Vitamin Packs!), knows this and proactively helps customers avoid potentially risky drug-nutrient interactions when recommending a unique-to-you daily supplement regimen. It’s the only personalized nutrition company that cross-references more than 650 potential medication interactions and peer-reviewed scientific studies with the information customers provide on their lifestyle, diet, health, and long-term wellness goals through an online assessment. (And if you’re unsure about your recommendations, they even have on-call nutritionists and registered dieticians making up their customer support team, offering science-backed and transparent suggestions.)

“It’s important to make sure you’re aware that certain supplements may interact with a medication that you’re on,” says Michael Roizen, M.D., Chief Wellness Officer at the Cleveland Clinic and Persona medical advisory board member. For instance, “some herbal supplements that contain St. John’s wort, which is sometimes used to ease anxiety, have been associated with worsening depression in those who are taking antidepressants, or rendered their birth control regimen much less effective. Vitamin K may reduce the ability of the blood thinners to work, and some antioxidant supplements, like vitamins C, might reduce the effectiveness of some types of cancer chemotherapy.”

Bottom line, a supplement routine is a simple way to make sure your body’s getting what it needs to function healthfully, but there’s no one-size-fits-all solution. Your body’s needs and your wellness goals are unique to you, so always check with your doctor when you’re considering taking any new supplement—beauty-boosting powders included.