The seeds of fenugreek (Trigonella foenum-graecum), a member of the legume family, are ground up and used to flavor curries, among other dishes. But you can also find fenugreek sold as a dietary supplement—in capsules, tinctures, and powders.
Fenugreek has long been used in traditional Indian (Ayurvedic) and Chinese medicine. Today it’s often promoted to control blood sugar and reduce cholesterol. Some marketers claim it helps increase weight loss and libido.
Rich in fiber, flavonoids (including quercetin), and other compounds, fenugreek has been shown in lab and animal studies to have anti-inflammatory, antioxidant, anticancer, and pain-relieving properties, and to help lower blood sugar and cholesterol. But its effects in people are less clear.
Several studies in recent years, including one from Jordan, found that high doses of fenugreek can lower blood sugar in people with diabetes. This is possibly due to the soluble fiber in the seeds, though other constituents may play a role, too. There’s also some evidence that fenugreek can decrease insulin resistance.
But other studies have not shown benefits, and a 2009 review in Canadian Family Physician concluded that there’s “very limited evidence to support the use of fenugreek in diabetes management.” More research is needed, especially on fenugreek’s long-term effects.
It has been proposed that fenugreek may lower blood cholesterol by inhibiting absorption of dietary cholesterol in the intestine and/or by increasing bile secretion (cholesterol is a component of bile). But the few studies in people have had inconsistent results. One small Iranian study found a drop in triglycerides in people consuming fenugreek seeds soaked in hot water, but no change in total or LDL (“bad”) cholesterol.
In a small 2009 study from the University of Minnesota, obese people who consumed fenugreek fiber (eight grams) at breakfast reported greater satiety, compared to people who didn’t consume the supplement—but there was no significant reduction in calorie intake for the whole day.
And in a 2010 French study, overweight men who took fenugreek seed extract for six weeks reduced their daily fat intake by 10 percent but had no changes in weight or body composition. Interestingly, fenugreek seeds are approved in Germany to treat loss of appetite.
A recent Australian study of men found that a standardized fenugreek supplement improved sexual arousal and orgasm, as well as muscle strength, “well being,” and energy, while a placebo did not. Fenugreek contains steroidal saponins that may have hormonal effects.
The study did not include men with erectile dysfunction, and the findings were preliminary at best.
Bottom line: Fenugreek has interesting properties that make it worth studying. But we recommend that you limit its use to cooking and skip supplements, since their benefits are unproven and their long-term safety unknown.
At least in theory, supplements may interact with some medications (including blood thinners), and they can cause gas, bloating, and diarrhea. Pregnant women and anyone with a hormone-sensitive cancer should especially avoid supplements.
Keep in mind that if high-dose fenugreek does lower blood sugar, its effects could be unpredictable and risky, especially in people with diabetes. In rare cases, allergic reactions to fenugreek may occur in people with allergies to other legumes.