Natural is in—because “natural” means safe, right? That’s not always the case. Arsenic is natural; so is hemlock and lead. “Natural” traditionally means free of man-made substances, and created by Mother Nature.

Complicating the matter, “natural” is now also a marketing term, for everything from cookies to toothpaste. Supplements can be especially dangerous “natural” products – some may be downright harmful. Naturally derived dietary supplements have been associated with everything from liver or kidney failure, to seizures and even death. The FDA is not authorized to review dietary supplement products for safety and effectiveness before they are marketed. This means it’s entirely up to the manufacturer to ensure that supplements do what they claim.

Here are some simple guidelines you can follow when shopping for “natural” products:

Avoid the following supplements often associated with injuries:

  • Ginkgo biloba: Ginkgo is marketed to enhance cognitive function, but it also interferes with our body’s ability to form clots. That’s why it’s associated with an increased risk of spontaneous hemorrhage and bleeding.
  • St. John’s wort: One of the most popular complementary and alternative treatments for depression in the US, side effects range from dizziness, to confusion and sedation. Most dangerously, St John’s wort prevents the function of other medications that you may need, such as HIV/AIDS medications, heart medications, transplant drugs and oral contraceptives. When combined with other anti-depressants, it can cause a life-threatening condition known as serotonin syndrome.
  • Laetrile and amygdalin: These supplements are marketed as having beneficial effects for cancer, but there’s no clinical data to support it. They’re also associated with cyanide poisoning, which is fatal.
  • Kava: Kava roots are typically used to create euphoric sensations and for their anesthetic properties, but unfortunately can cause liver failure.
More information can be found on the United States Pharmacopeial Convention database: http://www.usp.org

If you’re taking prescription medications, steer clear of supplements altogether. Some of the most dangerous outcomes from supplements occur when they’re combined with prescription medications. Supplements can either interfere with the prescription medication or enhance the effect of the prescription medication, leading to higher (and often toxic) drug levels.

More information can be found on the FDA’s site: https://www.fda.gov

Watch out for supplements often associated with contaminants. Since the products aren’t tested by the FDA, supplements are rampant with contaminants. A study done by BMC Medicine in 2013 showed that more than 59 percent of dietary supplements tested contained plant species not listed on the label.

  • Kelp: Scientists found arsenic at “higher than acceptable…levels” in eight of nine over-the-counter herbal kelp products.
  • Licorice, Indian rennet and opium poppy: These carry a high risk for contamination with toxic mold.
  • Black cohosh: This plant is typically marketed for premenstrual symptoms and menopause, but 25 percent of samples in one study didn't include black cohosh at all. Black cohosh has also been associated with liver necrosis and failure.
  • Tea: Tests of various tea leaves showed high levels of both lead and aluminum. How can you still have your cup safely? Organic white tea had lower levels of both aluminum and lead than organic green tea. Look for tea leaves that were brewed in Japan, as opposed to China, and steep for no more than three minutes.
More information can be found on the United States Pharmacopeial Convention database: http://www.usp.org

This same study done by BMC Medicine in 2013 also looked at 44 herbal products from 12 companies, 30 species of herbs and 50 leaf samples to see if their contents were related in any way to what their labels stated.

  • Only 48 percent contained what they claimed as the active ingredient. Of those, 1/3 were contaminated with ingredients and fillers; some that pose health risks, which are mentioned above.
  • Only two of 12 companies delivered what they promised on the label without any substitutions.
  • This study’s conclusion? Most of the herbal products tested had poor quality, including considerable product substitution, contamination and use of fillers.
More information can be found on the BMC Medicine website at: https://bmcmedicine.biomedcentral.com

What can you do?

Look for USP-verified supplements: When shopping for supplements, check the United States Pharmacopeial Convention, which tests supplements and gives those that pass their “verified” seal.

Get your “supplements” in the form of food—not a pill. Studies consistently show our health is predicted by the food we eat—not the supplements we take. Plus, it’s likely safer since you’re unlikely to go overboard on any nutrients.

The reality is that “natural” is not a carte blanche for safety. Mother Nature doesn’t intend it that way and we definitely cannot blindly assume that a supplement marketed as “natural” hasn’t been contaminated, or has been tested for safety.

Apply the same scrutiny to “natural” products that we do to the “unnatural” ones and we’ll all be safer.