Dietary Supplements and Natural Products: How to Fully Disclose Them to Your Care Team

Every year, millions of people in the U.S. and UK take dietary supplements-vitamins, herbs, fish oil, probiotics, or plant-based extracts-thinking they’re harmless because they’re "natural." But here’s the truth: supplements aren’t safe just because they’re on a shelf at a grocery store. Many interact with prescription drugs, worsen chronic conditions, or cause unexpected side effects. And the biggest danger? You’re probably not telling your doctor about them.

Why Your Doctor Needs to Know What You’re Taking

If you’re taking St. John’s wort for low mood, garlic pills for heart health, or glucosamine for joint pain, you’re not alone. Nearly 8 in 10 American adults use some kind of supplement. But only about one in three tell their doctor. That’s not just an oversight-it’s a safety risk.

Consider this: St. John’s wort, a popular herb for mild depression, can cut the effectiveness of birth control pills, blood thinners like warfarin, and even some antidepressants by up to 57%. A patient in a 2022 AMA Journal of Ethics case study had dangerous bleeding after combining ginkgo biloba with warfarin. She didn’t think her doctor needed to know about "natural" products. She was wrong.

The problem isn’t just herbs. Even common vitamins can be risky. High-dose vitamin K can undo the effect of blood thinners. Calcium supplements can interfere with thyroid medication. Green tea extract has been linked to liver damage in rare cases. And since supplements aren’t tested for safety before they hit the market, you can’t assume they’re harmless.

The Regulatory Gap: What’s Not Being Checked

Unlike prescription drugs, dietary supplements don’t need FDA approval before being sold. Under the Dietary Supplement Health and Education Act (DSHEA) from 1994, companies can sell products without proving they work-or even that they’re safe. The FDA can only step in after someone gets hurt.

That’s why you’ll see labels saying: "This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease." That’s not marketing fluff-it’s the law. The FDA doesn’t test these products. The manufacturer does. And many don’t even follow basic quality rules.

In 2022, the FDA inspected less than 1% of supplement factories. Meanwhile, over 85,000 different supplement products are available in the U.S. alone. That’s a lot of room for error. Some products contain hidden drugs, heavy metals, or far more active ingredient than listed. A 2023 study found that nearly 1 in 4 herbal supplements didn’t contain what they claimed.

Who’s Most at Risk-and Why They Stay Silent

People with chronic conditions are at the highest risk. About half of supplement users have diabetes, high blood pressure, heart disease, or other long-term illnesses. These are the exact conditions where supplements can cause serious harm.

But why don’t they tell their doctors? Many think their provider won’t care. Others fear being judged. Some believe supplements are "too natural" to matter. A 2019 study found that patients visiting conventional doctors disclosed supplement use just 33% of the time. That number jumps to 72% when doctors directly ask.

It’s not just about honesty-it’s about how the question is asked. If a doctor says, "Do you take any supplements?" most people say no. But if they ask, "What vitamins, herbs, or natural products are you using to help with your health?"-that opens the door. One nurse practitioner in Texas changed her question and saw disclosure rates double.

The Most Common Supplements With Hidden Dangers

Not all supplements are equally risky. But some stand out because they’re popular and interact with common medications:

• St. John’s wort: Reduces effectiveness of birth control, antidepressants, blood thinners, and HIV meds.
• Ginkgo biloba: Increases bleeding risk when taken with aspirin, warfarin, or NSAIDs like ibuprofen.
• Garlic supplements: Can thin blood and lower blood pressure too much when combined with antihypertensives.
• Green tea extract: Linked to liver injury in high doses, especially when taken on an empty stomach.
• Glucosamine/chondroitin: May affect blood sugar control in diabetics and interfere with blood thinners.
• Echinacea: Can overstimulate the immune system, risky for people with autoimmune diseases.

The 2009 National Health Interview Survey found disclosure rates for these were shockingly low-some under 10%. If you’re taking any of these, your doctor needs to know.

How to Talk to Your Care Team-Without Feeling Awkward

You don’t need to be an expert. You just need to be honest. Here’s how to make it easy:

1. Bring a list. Write down every supplement, herb, vitamin, or tea you take daily. Include the brand, dosage, and how often you take it. Don’t skip the "small" ones.
2. Use the right language. Say "I take ashwagandha for stress" instead of "I just take this herbal thing." The more specific you are, the better your provider can help.
3. Ask directly. Say: "Could this interact with my other medications?" or "Is this safe with my condition?"
4. Use a supplement log. Many clinics now give patients printable or digital logs to track what they take. Keep it updated.

At Mayo Clinic, using a simple log raised disclosure rates from 28% to 67% in just three years. It’s not complicated-it’s just consistent.

What Your Provider Should Be Doing

You shouldn’t have to push for this conversation. Doctors and nurses should be asking.

The American Medical Association recommends that every provider screen for supplement use at every visit. The National Institutes of Health offers free training for clinicians on how to talk about supplements. And as of early 2023, 87% of U.S. hospitals now require supplement questions during patient intake.

But many providers still lack training. Medical students get less than 3 hours of education on nutrition and supplements during all four years of school. That’s why some doctors still say, "It’s just a vitamin." That mindset is outdated-and dangerous.

If your provider brushes off your supplement use, ask for a referral to a pharmacist or integrative health specialist. Pharmacists are trained to spot interactions and can review your entire list in minutes.

What’s Changing-and What’s Next

There’s hope. The FDA launched the Dietary Supplement Ingredient Database (DSID-5) in January 2023, giving providers verified data on what’s actually in popular supplements. Epic Systems, the biggest electronic health record company, is adding a dedicated supplement module in mid-2024 that will automatically flag dangerous interactions.

The Supplement Safety Act, introduced in 2023, would require all supplements to be registered with the FDA before sale. Public support is strong-68% of Americans back it.

But until those changes fully roll out, the responsibility falls on you. Your health isn’t just about what’s in your medicine cabinet. It’s also about what’s in your supplement drawer.

Supplement Safety Checklist

Use this before your next appointment:

• ✅ I have a written list of all supplements, herbs, and natural products I take.
• ✅ I include brand names, dosages, and how often I take them.
• ✅ I’ve asked my provider: "Could any of these interact with my medications?"
• ✅ I’ve checked for interactions using trusted resources like the Natural Medicine Database or NIH’s Office of Dietary Supplements.
• ✅ I update my list every time I start or stop something.

What If I’ve Already Had a Bad Reaction?

If you’ve felt dizzy, nauseous, had unusual bleeding, or noticed your medication stopped working after starting a supplement, tell your provider immediately. Also, report it to the FDA’s Adverse Event Reporting System (CAERS). Even if you’re not sure it was the supplement, your report helps protect others.

You don’t need to prove it. You just need to share what happened. The FDA receives over 16,000 reports a year-but experts say less than 1% of actual reactions get reported. Your voice matters.