Taking Supplements May Have An Unexpected Effect On Your Liver

How many supplements do you take every day? Maybe just a multivitamin to fill nutritional gaps? Or perhaps you've added vitamin D, calcium, or fish oil for an extra health boost. Social media influencers, wellness bloggers, and even some doctors might have you reaching for turmeric to fight inflammation, elderberry for a cold, or valerian for better sleep.

(Read why you should stop believing this common supplement myth.)

But if your supplement shelf is starting to look like a mini pharmacy, it might be time to check in on your liver health. A 2022 article in Liver Transplantation reported that liver failure caused by herbal and dietary supplements has skyrocketed, an eightfold increase since 1995. While the study didn't pinpoint the worst offenders, a 2017 article in Hepatology linked 20% of drug-induced liver injuries to supplements for purposes such as bodybuilding, weight loss, and mood support. And it's not just anabolic steroids that can be risky. Green tea extract and those mysterious multi-ingredient blends could also be putting extra strain on your liver.

Your liver is responsible for more than 300 functions in your body, including processing nutrients and chemicals that enter your body. Many of the drugs and supplements you take are processed by the liver so they can be useful to your body. Birth control pills, statins, and some antibiotics are just some of the many drugs that can lead to liver injury. Painkillers and acetaminophen are common culprits of liver problems, especially when they're taken in large doses.

However, some of your favorite herbal supplements are also known to be toxic to your liver. According to a 2024 study in JAMA Network Open, turmeric, ashwagandha, red yeast rice, garcinia cambogia, green tea extract, and black cohosh are some of the most widely used supplements that could also pose a risk for liver injury. The researchers estimated that 15.6 million people in the United States have taken at least one of these herbal supplements in the past 30 days. 

As a whole, these herbal supplements are safe, but problems can occur if you're already taking other medications. For example, turmeric hasn't been associated with liver injury in the past, according to the National Institutes of Health. More accounts of liver injury appeared as supplement manufacturers began adding piperine (black pepper) to help the body absorb turmeric. One woman was already taking vitamins plus a bronchodilator and migraine medication; it wasn't until she took 500 milligrams of turmeric every day that she was hospitalized for acute hepatitis. 

It can be tempting to take a higher dose of a medication or supplement, particularly when you notice its health benefits, such as pain relief. Your liver can only metabolize a certain amount at a time, so you could risk liver damage even if you take more acetaminophen (Tylenol) at one dose. Warning signs of liver disease include nausea, pain in your upper right abdomen, dark urine, yellowing of your skin (jaundice), and loss of appetite. Some people may not experience any symptoms of liver damage.

Keep track of all medications and supplements you're taking so each doctor can be aware of potential drug-related liver injury. Try to keep the herbal supplements and other over-the-counter (OTC) drugs to a minimum, and look for any identical ingredients. For example, many cold medicines will also have acetaminophen, so you could be stressing your liver if you're already taking acetaminophen for arthritis pain.

Prescription medications and OTC drugs are approved by the Food and Drug Administration for safety, but supplements are not. You may already be taking turmeric to reduce inflammation, but other health supplements may have proprietary blends that could also include turmeric. Proprietary blends don't specify how much of an individual ingredient the supplement may have. Some supplements may not accurately report the ingredients stated on the label. A 2023 article in JAMA Network Open analyzed 57 supplements and found 89% of them didn't list all of the ingredients found in the product.