The market for health functional foods and nutritional supplements has been growing explosively lately, hasn't it? Among these, herbal supplements and specific extracts labeled natural are especially preferred. Unfortunately, the word natural does not guarantee safety. In fact, there is a steady rise in reports showing that ingredients widely believed to be healthy can cause fatal damage to the liver.
A prime example is green tea extract. Green tea is renowned for its potent antioxidant activity and is frequently used as a diet aid or fatigue reliever. However, highly concentrated green tea extract, particularly epigallocatechin gallate, can induce hepatotoxicity when ingested in excessive amounts. During hepatic metabolism, epigallocatechin gallate can overload specific enzyme systems or increase oxidative stress, leading to hepatocyte damage. This outcome may vary depending on diverse factors, including dosage, duration of use, individual genetic factors, and interactions with other medications.
Another example is black cohosh, used to alleviate climacteric symptoms in women. Many women choose this as a natural hormone replacement therapy, yet cases have been reported where it caused severe liver injury and even liver failure requiring liver transplantation. While the hepatotoxicity mechanism of black cohosh is not yet fully understood, it is presumed to stem from abnormal hepatic metabolic reactions or idiosyncratic constitution-related responses.
In addition, excessive intake of vitamin A, high doses of niacin (vitamin B3), and certain weight-training supplements among various health supplements can trigger hepatotoxicity. Such liver injury often starts asymptomatic and progresses gradually before manifesting with symptoms like jaundice, fatigue, and right upper quadrant pain. In early stages, it presents as elevated liver enzyme levels, including alanine aminotransferase and aspartate aminotransferase, on a blood test, and severe cases can dangerously progress to acute hepatitis, chronic hepatitis, and liver failure.
Modern medicine actively studies and warns against this drug-induced liver injury. Herbal supplements and health functional foods require particular caution because, unlike pharmaceuticals, they often do not undergo rigorous clinical trials before release, and their exact ingredient contents may remain ambiguous. Indiscriminately taking multiple products without consulting a physician or pharmacist places an intolerable burden on the liver, the body's detoxifying organ. Rather than blindly following claims that something is good, the wisdom to understand one's own body and seek professional guidance is more vital now than ever.
