Milk Thistle

Herbal products have become increasingly popular, especially among individuals with chronic diseases. Herbalists and physicians alike used the milk thistle (Silybum marianum), an annual or biennial herb from the Mediterranean region, for hundreds of years to treat a wide range of liver pathology, including fatty liver disease, hepatitis, and cirrhosis, and to protect the liver from environmental toxins.[1] Today, millions of people consume milk thistle to support healthy liver function. The ripe seeds are primarily the medicinal part of the plant.[2] Researchers have focused their efforts on studying silymarin, a mixture of flavonolignans extracted from milk thistle, and the most active ingredient of this extract, silybin.[3] Silymarin and silybin have become some of the most prescribed natural compounds, and the 2 names are often interchangeable. However, each has a different clinical purpose, but there are no definitive results in terms of clinical efficacy. Currently, herbal products such as milk thistle in the United States are not considered drugs and do not have the same level of regulation as drugs from the US Food and Drug Administration (FDA).[4] Like most herbal products, the FDA does not approve or recommend milk thistle as a treatment for any medical condition.
Recent studies have focused on the role of milk thistle in treating nonalcoholic fatty liver disease, a common hepatic manifestation of metabolic syndrome. The prevalence of NAFLD in Western countries is approximately 20% to 30%.[5][6] Currently, there is no consensus approach when it comes to the treatment of NAFLD. Most clinicians approach the disease by emphasizing lifestyle modification, including diet, weight loss, and limiting alcohol intake. However, study results suggest milk thistle can benefit patients with NAFLD. Data indicate that silymarin treatment correlated with reduced insulin resistance and decreased fasting insulin levels significantly. Patients treated with 600 mg/d of silymarin for 12 months demonstrated lower fasting insulin levels.[7] A separate clinical trial evaluated silymarin’s effectiveness compared to metformin and pioglitazone in NAFLD patients. Research showed that patients treated with silymarin had significantly lower transaminase levels than those treated with metformin or pioglitazone.[8] In a sample of 25 patients treated for 4 months with 200 mg of silymarin 3 times a day before meals, there was a significant reduction in blood glucose levels (from 156 ± 46 mg/dL to 133 ± 39 mg/dL) compared to an increase in the placebo-treated group. In the same period, their HbA1c levels also dropped by an average of 1 point. The same group of patients also demonstrated significantly reduced total cholesterol, triglycerides, and LDL levels.[9][10] Another study aimed to evaluate the efficacy of combined treatment, which includes vitamin E, silybin, and phospholipids, and demonstrated that this complex improves liver damage, especially plasma markers of liver fibrosis and insulin resistance.[11] In Europe, intravenous preparations of purified silibinin are approved as an antidote to Amanita phalloides, a mushroom toxin that causes severe liver damage.[12]