Iron is essential for making healthy red blood cells, but it is also one of the supplements that can become dangerous when taken without a proven need. The NIH warns that extremely high iron doses can cause organ failure, coma, convulsions, and death.
Long-term excessive iron intake can also harm the liver, especially in people with iron overload conditions. EFSA notes that excessive iron intake over prolonged periods can have negative health effects, particularly on the liver. Iron supplements should usually be taken after blood tests confirm low iron or anemia.
6. Green Tea Extract
Drinking normal green tea is very different from taking concentrated green tea extract capsules. LiverTox reports that green tea extract has been linked to clinically apparent acute liver injury, including rare cases of acute liver failure.
The concern is especially linked to concentrated extracts often used in weight-loss or “fat burner” supplements. Anyone who develops yellow skin or eyes, dark urine, stomach pain, unusual fatigue, nausea, or loss of appetite after using green tea extract should stop the supplement and seek medical advice.
