Milk thistle shows promise as a defense against diabetes and diabetes-related complications, including damage to the kidneys and blood vessels. Often used to boost liver health and support detox efforts, milk thistle is rich in antioxidants (natural substances known to knock out free radicals). In turn, many diabetes-related complications are linked to oxidative stress (a process that results from overproduction of free radicals). By protecting against oxidative stress, studies suggest, milk thistle may aid in the treatment of diabetes.
Research on Milk Thistle for Diabetes
So far, few studies have tested milk thistle's effects on people with diabetes. The available research includes a 2006 study (published in Phytotherapy Research), which included 51 people with type 2 diabetes. For four months, participants paired their conventional therapy with either a placebo or a supplement containing silymarin (an antioxidant complex extracted from milk thistle). By the study's end, members of the silymarin group showed a significant decrease in total cholesterol and LDL ("bad") cholesterol. In addition, silymarin appeared to help regulate their blood sugar levels.
Laboratory tests suggest that milk thistle may also help manage diabetes by treating insulin resistance. In a 2005 report published in Medical Hypotheses, for instance, scientists note that both silibinin (an antioxidant found in silymarin) and resveratrol (an antioxidant available in the skin of red grapes) may help reverse insulin resistance by working against IKKbeta (an enzyme shown to disrupt insulin signaling).
Additionally, there's some evidence that milk thistle may help counter diabetes-related kidney damage (a condition known as diabetic nephropathy). For example, an animal study published in Renal Failure in 2010 showed that milk thistle slowed up the progression of diabetic nephropathy in a group of rats.
Using Milk Thistle for Diabetes
The National Institutes of Health classifies milk thistle as "possibly effective" for diabetes. However, using milk thistle in place of prescribed diabetes treatment can have serious health consequences. If you're considering the use of milk thistle (or any other herbal remedy) in treatment of diabetes, it's crucial to consult your physician before starting your supplement regimen.
Huseini HF, Larijani B, Heshmat R, Fakhrzadeh H, Radjabipour B, Toliat T, Raza M. "The efficacy of Silybum marianum (L.) Gaertn. (silymarin) in the treatment of type II diabetes: a randomized, double-blind, placebo-controlled, clinical trial." Phytother Res. 2006 Dec;20(12):1036-9.
McCarty MF. "Potential utility of natural polyphenols for reversing fat-induced insulin resistance." Med Hypotheses. 2005;64(3):628-35.
National Institutes of Health. "Milk thistle: MedlinePlus Supplements". January 2011.
Vessal G, Akmali M, Najafi P, Moein MR, Sagheb MM. "Silymarin and milk thistle extract may prevent the progression of diabetic nephropathy in streptozotocin-induced diabetic rats." Ren Fail. 2010 Jul;32(6):733-9.