Initial Posting: 1/5/2016    Last Update: 5/16/2019
Question: Does guggul really improve thyroid function?
Answer: Guggul, a tree resin commonly used in Ayurvedic medicine to treat a variety of conditions, is sometimes also promoted to enhance thyroid function. However, there is little evidence to support this use. In fact, the suggestion appears to be based a single animal study which found guggul increased iodine uptake and certain other measures of thyroid function in rats with chemically-induced low thyroid function (Tripathi, Planta Med 1988). There do not appear to be any randomized, placebo-controlled, peer-reviewed studies in people. (Interestingly, in a small study among adults who took 2,160 mg of guggul daily for three months, two people reported tiredness and "relapse" of their hypothyroidism (Nohr, Complement Ther Med 2009)).
More information about other proposed uses of guggul, such as cholesterol lowering and weight loss, is found in the article about Guggul. Also see the article about Hypothyroidism, which discusses herbs and supplements to use only with caution with this condition.