Milk Thistle - Scientific Background
Silymarin protects the liver against some poisons.
Milk thistle contains a complex of antioxidant flavonoids, collectively known as silymarin, which have shown evidence of specific protective effects on liver cells exposed to a variety of poisons (Flora et al 1998). Such poisons have included dry-cleaning fluids, various solvents, acetaminophen (e.g., Tylenol®), and others (Hall et al 1994; Shear et al 1995; von Schonfeld et al 1997).
Silymarin may help the liver recover from poisoning and inflammation.
Among industrial workers with biochemical evidence of liver damage following long-term exposure to organic solvents, test results for abnormal liver function improved after a 30-day treatment with silymarin (Szilard et al 1988).
Preliminary evidence suggests that silymarin improves the chances of recovery in individuals who ate liver-damaging (hepatotoxic) mushrooms (Parish and Doering 1986) and that it may improve liver function in patients with chronic, active inflammation of the liver (hepatitis) (Buzzelli et al 1993).
Long-term use of silymarin may help recovery from alcoholic liver damage.
Silymarin may improve glucose levels and insulin status among insulin-dependent diabetics with alcoholic cirrhosis of the liver (Vekussi et al 1997).
A 4-year treatment trial among 170 patients with cirrhosis (54% with alcoholic cirrhosis) showed a 30% lower fatality rate among those treated with silymarin (Ferenci et al 1989).
However, in three randomized, controlled, clinical trials of silymarin therapy, after 3 months of treatment for chronic alcoholic hepatitis, patients receiving silymarin showed no difference from the placebo group in clinical outcome or survival (Trinchet et al 1989). No differences were observed after 2 years of treatment for alcoholic cirrhosis (Pares et al 1998).
Milk thistle and its extracts do not influence the intensity or duration of acute alcohol intoxication and are not known to be effective in the treatment of acute alcohol-related illness (Varga et al 1991; Michel et al 1993).
Silymarin may have other health benefits.
Further studies have shown that silymarin has a protective effect against oxidation of low-density lipoprotein (LDL, the bad cholesterol) and against substances that can cause skin cancer (Ahmad et al 1998; Krecman et al 1998).
