Effects of modified Atkins diet on thyroid function in adult patients with pharmacoresistant epilepsy.

•Possible long-term effects of modified Atkins diet (MAD) in epilepsy are mainly unknown.•This is the first study on the effect of MAD on thyroid hormone function in adults.•A slight, but significant reduction in thyroid hormone levels was observed.•The effect was independent of enzyme-inducing ASMs or nonenzyme-inducing ASMs.•We suggest clinicians to monitor thyroid hormones when MAD is used.