Does milk thistle help with diabetes? What the research does and doesn't show

The evidence doesn't support milk thistle as a treatment for diabetes on its own, and no trial has tested it that way in a general or non-diabetic population. What exists is a pooled analysis in which glucose, insulin and HbA1c came out lower with silymarin than with placebo in people who already had a metabolic condition, plus smaller trials specifically in diabetic kidney disease that don't agree with each other.

What the evidence doesn't support

It doesn't support milk thistle or silymarin as a treatment for type 1 or type 2 diabetes, prediabetes, or as a replacement for a prescribed diabetes medication or insulin. Every trial below was run in people already diagnosed with diabetes or a related metabolic condition, receiving it alongside their usual care, not as something a healthy person takes to manage blood sugar. Nothing here describes a specific product's dose, and nothing here is a claim about any product.

What the trials found

A 2024 systematic review and dose-response meta-analysis pooled 33 controlled trials (1,943 participants) on silymarin's effect on cardiometabolic risk factors. Across the pooled trials, fasting blood glucose, fasting insulin and HbA1c were all lower with silymarin than with placebo or no treatment. The abstract doesn't break out results by each trial's specific diagnosis, but the wider silymarin literature — including the trials below — is concentrated in people already living with diabetes or another metabolic condition. The authors call for larger, longer trials before the findings are confirmed.

Two smaller randomized trials looked specifically at diabetic kidney disease. A 2012 trial gave 60 people with type 2 diabetes and diabetic nephropathy 420 mg/day of silymarin for three months, on top of their usual blood-pressure medication, and found a significantly larger drop in urinary albumin (a marker of kidney damage) with silymarin, and urinary markers of inflammation and oxidative stress were lower in that group too. A larger 2017 trial in 102 people with the same underlying condition, adding silymarin or placebo to standard kidney-protective medication, found no significant difference between groups in kidney function decline, dialysis need or death over the study period — though hospitalization rates were lower in the silymarin group. The two trials' primary outcomes don't agree, and the dose used in the 2017 trial wasn't reported in its published abstract.

Separately, a 52-week trial gave obese adults with type 2 diabetes and metabolic syndrome a combination product containing both silymarin and berberine (silymarin was included specifically to improve berberine's absorption). That combination group saw improvements in fasting glucose, insulin, cholesterol markers, BMI and abdominal fat versus placebo — but because it's a two-ingredient product and berberine itself has documented metabolic effects, the result can't be credited to milk thistle alone.

Trial	Population	Result
Mohammadi 2024 (33 pooled trials, n=1,943)	Adults with cardiometabolic risk factors	Glucose, insulin and HbA1c lower with silymarin
Fallahzadeh 2012 (n=60)	Type 2 diabetes with diabetic nephropathy	Larger drop in urine albumin vs. placebo
Voroneanu 2017 (n=102)	Type 2 diabetes with diabetic nephropathy	No significant difference in kidney outcomes vs. placebo
Di Pierro 2017 (n=136, combination product)	Obese adults with type 2 diabetes and metabolic syndrome	Improved glucose, insulin, cholesterol, BMI vs. placebo — not milk thistle alone

Questions people ask

Is milk thistle good for diabetes?

The evidence is mixed and every trial was run in people already diagnosed with diabetes or a related condition, alongside their usual care. A 2024 pooled analysis found glucose, insulin and HbA1c came out lower with silymarin than with placebo; trials specifically in diabetic kidney disease found different results from each other.

Is milk thistle good for diabetes type 2?

Same evidence as above — trials exist only in people already diagnosed, and no trial tested milk thistle as a diabetes-prevention strategy or as something that lets someone stop a prescribed medication.

Does milk thistle help insulin resistance?

A 2024 pooled analysis of 33 trials found lower fasting insulin with silymarin than placebo, in people with existing cardiometabolic conditions — not a general population, and not tested against a placebo in people without any metabolic diagnosis.

When to talk to a doctor

Anyone with diagnosed diabetes or prediabetes should manage it with a doctor's guidance; milk thistle is not a treatment for diabetes, and every trial above was run alongside standard medical care, not instead of it. If you take insulin, metformin or another diabetes medication, ask a doctor before adding milk thistle — see milk thistle and medications: what to check.

Related reading: milk thistle benefits: what the research does and doesn't show, milk thistle and weight, and milk thistle and cholesterol.