computer generated image of liver with green gallbladder

Green Tea Extract: ‘The food supplement that ruined my liver’

Sipping on organic green tea in the mornings or throughout the day is great for various reasons. It may some protection from dementia, encourage a healthy metabolism, and aid insulin sensitivity (1). But taking food supplements like green tea extract pills is a totally different story. In 2018, then 50-year-old Jim McCants of Prosper, Texas, learned this the hard way, and the lesson nearly cost him his life.


Man Fought for His Life after Green Tea Extracts Damaged His Liver

a representation of an unhealthy liver

Working as a finance manager, McCants began to feel wary of his health. He was approaching the age that his father died prompted his decision to start taking his health seriously and start training to become a physician’s assistant.


My dad had a heart attack at aged 59 and he did not make it. There’s a lot that he missed out on with us and I was determined to do what I can to take care of myself as best I can, so that I don’t miss out,” he says (2).

He developed very active habits, incorporating 5 or 6 workouts into his weekly routine, and he started to take Vitacost green tea extract supplements to encourage weight loss.


It was shocking because I’d only heard about the benefits,” remembers Jim. “I’d not heard about any problems.”

Then, 2 to 3 months after starting to take the food supplements, McCants’ body started to react. While he and his wife, Cathleen, were attending their youngest son’s graduation, he suddenly began to show signs that something had gone very wrong.


Your face is yellow, your eyes are yellow, you look terrible,” McCants recalls Cathleen saying to him.

Alarmed by his sudden change of appearance, McCants admitted himself to a nearby hospital, suspecting some type of liver damage. His medical team asked him about his lifestyle to help rule out what possible toxins could be putting so much stress on his liver. They ruled out smoking, alcohol, and prescription drugs since McCants hadn’t used any of those. But when they asked about over-the-counter food supplements, the green tea extract pills fit the bill. Just 3 weeks after submitting to a series of diagnostic tests, McCants received terrifying news:


She said you need a liver transplant. This has to happen fast. You have days – you don’t have a week.

Fortunately for McCants, a match was found within 24 hours, and he survived a successful liver transplant. Now, four years later, he still lives under the shadow of that health emergency. He now lives with kidney disease, chronic pain in his abdomen, and chronic fatigue. Nevertheless, McCants is grateful for his life and hopes others can learn from his experience. He’s also pursued a lawsuit against Vitacost. He wants them to update their product labels with strong warnings that inform potential buyers of the true risk of their over-the-counter supplements.


I didn’t expect harm. I expected that I might waste my money, I may take these and they don’t do a bit of good. I can accept that risk, but the risk that it could cause my liver to fail, that’s a risk that’s too high for somebody to take.

Currently, Vitacost’s product label has the following warning, but no mention of a risk of liver damage in otherwise healthy individuals:


Pregnant or lactating women, those with diabetes, hypoglycemics, and people with known medical conditions and/or taking drugs should consult with a licensed physician and/or pharmacist prior to taking dietary supplements. Keep out of reach of children.

What’s the difference? Green Tea Vs. Green Tea Food Supplements?

green tea

Drinking green tea has its benefits and it would be extremely hard to drink enough to cause harm, however, food supplements have the potential to be dangerous. Green tea food supplements are a concentrated form of green tea, with high levels of catechins (a type of antioxidant). Epigallocatechin gallate (EGCG) is the most usually the main active ingredient in extracts.

  • A cup of green tea steeped for 3 minutes can have an EGCG content of about 50mg/100 mL (3)
  • One capsule of Vitacost’s green tea extract pills, for example, has 250 mg of EGCG (4)

Research has found that consuming green tea can positively affect weight loss (5, 6), so those considering turning to over-the-counter supplements for weight loss should be happy to know that the more that the tea can still be supportive, and it safer.


According to EFSA, supplements dosed at 800mg or more of green tea, catechins may pose a danger. If you still decide to take a supplement, be sure to seek quality. Look for something that is pure (third-party tested for impurities and label claims). Always consult your medical care provider before you start a supplement, even if it can be bought over the counter.


There are no real shortcuts to a healthier life. It might be tempting to use a dietary supplement to speed up weight loss, but your best bet is to slowly build healthy habits like eating whole foods and staying active throughout the day. These types of changes end up being permanent, unlike crash diets and potentially toxic diet pills.

Are Green Tea Extract Pills Safe for Your Liver?

green tea food supplement extracts

A 2016 review of over 30 studies found that liver damage from green tea extract pills was possible but rare. However, in recent years, there has been an increase in cases of adverse effects from these dietary supplements, and medical care providers and governing bodies alike are cautioning consumers to think twice about their safety. 

Jim McCants’ story, unfortunately, isn’t an anomaly. In 2017, Consumer Reports raised the alarm about new research which suggested that over-the-counter supplements marketed for bodybuilding or weight loss were causing more cases of liver damage than ever before. Green tea extract pills specifically have been partially linked to two deaths. (7) We’re thankful that McCants’ story didn’t end the same way.

So, why are green tea pills still on the market?

  1. For starters, they’re regulated as food, not as medication. The FDA doesn’t have authority to review dietary supplements, but they have published a message of caution to consumers looking to try them.
  2. People’s bodies can respond differently to weight loss supplements. Dr. Herbert Bonkovsky explains, “Usually people are taking these green tea extracts trying to lose weight, so they’re often not eating. We know from animal studies that fasted animals absorb a much higher percentage of the catechins than do fat animals.”
  3. Pinpointing which toxin caused liver damage can be tricky. If other facts such as alcohol, smoking, or prescription medications are also at play, doctors can’t always be certain if a dietary supplement is to blame for liver damage.

Other Green Tea Food Supplement Side Effects

Aside from the potential negative effect on the liver (the symptoms of which include jaundice, loss of appetite, abdominal pain, and dark urine), possible side effects include: (8)

  • Nausea
  • diarrhea
  • upset stomach
  • headache
  • dizziness
  • fast/irregular heartbeat
  • mood changes
  • insomnia
  • shakiness
  • seizures

For a more detailed look at the existing evidence on Green Tea and Green Tea supplements head over to

Keep Reading: “My journey to hell and back”: What I want people to know about Hyperemesis Gravidarum.

Social Media Image Source: BBC News


  1. 10 Evidence-Based Benefits of Green Tea.” Healthline. Kris Gunnars, BSc. April 6, 2020.
  2. ‘The food supplement that ruined my liver’.” BBC. October 25, 2018.
  3. Effects of different brewing conditions on catechin content and sensory acceptance in Turkish green tea infusions.” NCBI. Sena Saklar, et al. October 2015.
  4. Effects of catechin enriched green tea on body composition.” Pub Med. Hongqiang Wan, et al. April 2010
  5. Effectiveness of green tea on weight reduction in obese Thais: A randomized, controlled trial.” Science Direct. ParadeeAuvichayapa, et al. February 27, 2008
  6. Health Canada toughens green tea extract warnings.” CBC. David Common. November 15, 2017
  7. “Green Tea Extract.” WebMD