6 Facts to Know About Supplements Before Taking Them

Learn more about supplements, how they can help and which ones could pose health risks

Learn more about supplements, how they can help and which ones could pose health risks

Walk down the vitamin and mineral aisle of any drugstore and you’ll see rows of capsules, liquids and powders — all packaged to suggest they’ll improve your health and well-being. Before self-prescribing and incorporating supplements into your diet, do your homework on this emerging market.

Not all supplements will be effective, and any potential positive and negative impacts should be considered.

“It’s important to be an informed consumer of dietary supplements if you choose to take them,” says Immanuel Hausig, DO, a family medicine physician at Scripps Coastal Medical Center in Carlsbad.

Check out these 6 facts about supplements to help you make healthy decisions.

1. Supplements are regulated, but not necessarily tested and proven through clinical trials

The supplement industry is a $30 billion industry, with an estimated 80,000 to 90,000 supplement products in the market. However, while prescription medication undergoes rigorous testing and clinical trials before making it to the consumer, supplements do not.

“The United States Food & Drug Administration doesn’t regulate the health claims made by supplement manufacturers,” says Dr. Hausig.

“In fact, the Dietary Supplement Health and Education Act of 1994 doesn’t require that manufacturers prove supplements are safe before they are offered for sale. The manufacturers just have to prove supplements are produced in safe conditions, which is a subtle difference.”

The U.S. Pharmacopeial Convention (USP) verification program tests supplements and offers a verification logo to help consumers choose supplements that have undergone a rigorous testing process. NSF International and Consumer Lab are other seals that ensure a high-quality standard.

2. Supplements can’t replace a healthy diet and exercise

Vitamins, minerals and other supplements are not a substitute for a healthy lifestyle, but they can be used to fill in nutritional gaps and improve your health. 

Examples include:

  • Folic acid for women who are planning to get pregnant or are pregnant
  • Vitamin B12 for patients on proton pump inhibitors (PPIs) and H2 blockers and for vegans and vegetarians
  • Vitamin D3, calcium, magnesium and vitamin K for osteoporosis 
  • Omega 3 fish oils for high triglycerides
  • Vitamin E for fatty liver
  • Glucosamine and chondroitin for osteoarthritis 
  • Melatonin for sleep
  • Vitamin C and zinc for colds

“People who are taking certain medications — say, for example, proton pump inhibitors like Nexium or Prilosec, or metformin for diabetes — are known to be at risk for developing certain vitamin and mineral deficiencies,” Dr. Hausig says.

For instance, according to Dr. Hausig, the prescription antacid PPIs can deplete magnesium, while glucose-management medication such as metformin can cause Vitamin B12 deficiency.

3. If you’re taking supplements, tell your physician

Some supplements can interfere with the action of prescription medications. In addition, some supplements may be inappropriate for people with certain chronic diseases.

For example, excess calcium can contribute to coronary artery disease, and niacin can elevate blood sugar in diabetics. Patients with hemochromatosis, a disorder involving too much iron in the body, should avoid iron and vitamin C.

4. Some supplements have been validated by clinical trial

There is strong, longstanding, evidenced-based research for some supplements, including plant sterols, omega-3 fatty acids, niacin, vitamin B6 and B12, and tree nuts.

“More and more data comes out every year about supplement effectiveness,” Dr. Hausig says.

When in doubt, ask your physician.

5. Some supplements have high-risk drug interactions

Certain supplements may interact with your medications or increase your risk of experiencing side effects from medications. Some supplements are known to carry an increased risk of liver injury. Others may decrease the blood’s ability to clot, including fish oil, ginkgo biloba, garlic and vitamin K.

Additionally, excess vitamin E can increase chances of hemorrhage or uncontrolled bleeding. Too much vitamin D may also cause non-specific symptoms such as poor appetite, weight loss and heart arrhythmias. High doses of vitamin A can cause birth defects.

The National Institutes of Health website has a database of supplements labels. If you’re currently taking prescription medication, talk with your doctor before beginning a new supplement regimen.

6. Vitamin supplements can have side effects

Because supplements are a wide-ranging category, they may carry the same risk for broad side effects as pharmaceutical drugs, from digestive upset and diarrhea to interfering with hormonal birth control and beyond.

The U.S. Department of Health & Human Services maintains an Office of Dietary Supplements that provides fact sheets on many common supplements, including side effects.

 “When it comes to dietary supplements, more isn’t necessarily better,” says Dr. Hausig. “If you’re taking several over-the-counter supplements every day, you should definitely have a conversation with your doctor to clarify what your goals are, ensure none of them are counteracting each other or your prescribed medications, and see if you even need to be taking them.”