Do Your Nutritional Supplements Contain the Ingredients They Say They Do?

Not all pills, capsules and powders do what they claim, and some contain unapproved and even dangerous ingredients.

vitamins and supplements, minerals

Half of all US adults take dietary supplements, according to the Centers for Disease Control and Prevention, believing these pills, powders and drinks can increase vitamin and mineral intake, up energy levels and address a slew of other purported health benefits.  

Americans spend about $35 billion a year on dietary supplements, which may only be beneficial to people in certain populations, like vegans and those with conditions that prevent proper fat absorption, like Crohn's disease. However, supplements can also increase the risk of complications during surgery, like bleeding and an altered response to anesthesia. They may also cause harmful drug interactions and side effects, like headaches and nausea. A 2015 study published in the New England Journal of Medicine found that an estimated 23,000 Americans visit the emergency room for complications related to dietary supplements each year.

Brush up on the facts before you begin taking any supplements; these five tips can help.  

Do your homework

Supplements don't prevent, treat or cure diseases like prescription medications can, and manufacturers aren't required to follow the same stringent regulations, either. The US Food and Drug Administration does not have the authority to review dietary supplements before they hit the shelves like they do with prescription medications. Instead, manufacturers and distributors are responsible for ensuring the safety of their products before they go on sale. That means there's no guarantee the supplement was tested thoroughly, if at all.

A September 2018 study published in Clinical Toxicology suggests not all supplements contain the ingredients or amount of ingredients they claim. Researchers analyzed 24 weight loss and pre-workout supplements to determine the level of higenamine—a stimulant that might harm your heart health. Just five products contained the quantity of the ingredient listed on the package.

In another study published in JAMA Network Open in October 2018, researchers looked at more than 700 US Food and Drug Administration-issued warnings about dietary supplements tainted with unapproved ingredients between 2007 and 2016. A majority of the supplements in question were taken for sexual enhancement, weight loss or muscle building. The contaminants were typically pharmaceutical drugs with the potential to cause serious adverse reactions or interactions with other medications.

In almost 98 percent of cases, the harmful or forbidden ingredients weren't listed on the supplement packaging, and approximtely 20 percent of supplements contained more than one unapproved ingredient.

Just 46 percent of these products were voluntarily recalled, and not all manufacturers and distributers were diligent in removing potentially harmful ingredients from their products. According to the research, of the products found to be contaminated more than once, almost 68 percent had new drug ingredients reported in their second or third warnings. So, dangerous supplements are still available to consumers despite warnings.

There's no shortage of web sites for supplements, the trick is knowing where to look for reliable information. Check government sites like the National Institutes of Health or talk with your pharmacist, and always get your doctor's okay before starting a new supplement.

Beware of false claims

Folic acid helps prevent birth defects, like spina bifida and anencephaly, and research suggests calcium and vitamin D supplements can improve bone health. But not all supplements do what they claim, and many need more research. Not surprisingly, many weight-loss supplements—a.k.a. fat burners or appetite suppressants—don't keep weight off long-term, and some have harmful side effects, according to the National Institutes of Health.

Watch out for the word "natural," too. It doesn't always mean a supplement is safe. Some natural herbs may be considered safe, but they can become contaminated during processing or may be intentionally contaminated with actual prescription drugs.

Others, like kava and comfrey—banned in oral form in the US, and available for purchase only as an ointment (which may still be harmful)—can cause liver damage. St. John's wort, an herb used to treat depression, can make birth control and other medications less effective.

Keep your doctor informed

Proper dietary supplement regimens vary from person to person, based on your specific needs. Talk with your doctor before you start, and keep him or her up to date on any changes. This seems simple, but many people don't share their supplement intake with their healthcare providers.

A 2018 cross-sectional survey published in the British Journal of General Practice suggests one-third of 149 participants over the age of 65 who are also taking prescription medications hadn't disclosed supplement use to their doctor. There are a number of medications affected by supplement use, but vitamin K, for example, can reduce the efficacy of blood thinners taken to prevent clots. 

Follow directions carefully

Never take more than the recommended dose or combine supplements. Avoid taking supplements with other medications, or substituting supplements for actual medication.

Also, read package warning labels. Women who are pregnant or nursing, people who have allergies to any ingredients, young children and older adults should never take supplements without their doctor's approval. Your doctor can also assess your risk of taking supplements with an existing condition or of combining it with other medications.    

Don’t take supplements with these ingredients

There are 15 ingredients found in dietary supplements that people should always avoid, according to a Consumer Reports study. These dangerous ingredients have the potential to cause kidney and liver failure, paralysis, seizure, possible death and more.

  • Aconite
  • Caffeine Powder
  • Chaparral
  • Coltsfoot
  • Comfrey
  • Germander
  • Greater Celandine
  • Green Tea Extract Powder
  • Kava
  • Lobelia
  • Methylsynephrine
  • Pennyroyal Oil
  • Red Yeast Rice
  • Usnic Acid
  • Yohimbe

Whether or not you’ll experience severe side effects depends on three factors: how much and how long you’ve been ingesting the ingredients, and if you have a pre-existing condition.

Many of these ingredients—like caffeine powder, methylsynephrine and red yeast rice—may interact with statins taken to lower cholesterol, drugs like aspirin that have blood-thinning properties and other stimulants. The study concluded the health benefits of these ingredients don’t justify the risks, and yet these ingredients can be found readily in supplements at your local drug store.

Many healthy adults can get the recommended vitamins and minerals from their diet alone, making supplements unnecessary. Talk to your doctors, pharmacist and dietitian about any supplements you're interested in taking. They can help you determine which supplements, if any, could be valuable for you.

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