The liver processes everything, including supplements. Most are fine. A few have caused documented liver injuries. Here's what you need to know.
Supplements with Documented Liver Risk
Green tea extract (high dose) - In concentrated form (400-800mg EGCG), reports of severe liver injury exist. Lower doses and drinking green tea are fine. The problem is megadose extracts.
Kava - Traditional Pacific Islander preparation seems safer than commercial extracts. Several countries have restricted kava due to liver concerns.
Weight loss supplements - Many contain undisclosed ingredients. OxyELITE Pro, Hydroxycut (older versions), and similar products have caused liver failures.
Anabolic steroids and prohormones - Still sold as "supplements" sometimes. Liver toxicity is well-established.
High-dose vitamin A - Preformed vitamin A (retinol) can accumulate and cause liver damage at high doses over time. Beta-carotene is safer.
Generally Safe for the Liver
Most mainstream supplements don't harm the liver:
- Vitamin D, B vitamins, vitamin C - Magnesium, zinc, iron (at normal doses) - Omega-3 fatty acids - Probiotics - Common amino acids - Creatine
Milk thistle and NAC actually support liver health and are used clinically.
How to Protect Yourself
Buy from reputable brands. Contamination and undisclosed ingredients are the biggest risks. Third-party testing matters.
Don't megadose. More is not better. Stick to recommended amounts.
Be careful combining. Multiple supplements plus medications plus alcohol adds liver burden.
Watch for warning signs. Fatigue, dark urine, yellowing skin, right upper abdominal pain. Stop supplements and see a doctor.
Get baseline liver tests. If taking multiple supplements, periodic liver function tests are reasonable.