Effect of Vitamin E Supplementation on Chronic Insomnia Disorder in Postmenopausal Women: A Prospective, Double-Blinded Randomized Controlled Trial

Chronic insomnia disorder is one of the most common problems in postmenopausal women, exacerbated by underdiagnosis and improper treatment. This double-blinded, randomized, placebo-controlled trial was conducted to evaluate the potential of vitamin E to treat chronic insomnia as an alternative to sedative drugs and hormonal therapy. The study enrolled 160 postmenopausal women with chronic insomnia disorder, divided randomly into two groups. The vitamin E group received 400 units of mixed tocopherol daily, while the placebo group received an identical oral capsule. The primary outcome of this study was sleep quality assessed by the Pittsburgh Sleep Quality Index (PSQI), a self-evaluated and standardized questionnaire. The secondary outcome was the percentage of participants using sedative drugs. There were no significant differences in baseline characteristics between the study groups. However, the median PSQI score at baseline was slightly higher in the vitamin E group compared with the placebo (13 (6, 20) vs. 11 (6, 20); p-value 0.019). After one month of intervention, the PSQI score was significantly lower (indicating better sleep quality) in the vitamin E group compared with the placebo (6 (1, 18) vs. 9 (1, 19); p-value 0.012). Moreover, the improvement score was significantly higher in the vitamin E group compared with the placebo (5 (−6, 14) vs. 1 (−5,13); p-value < 0.001). In addition, there was a significant reduction in the percentage of patients using sedative drugs in the vitamin E group (15%; p-value 0.009), while this reduction was not statistically significant in the placebo group (7.5%; p-value 0.077). This study demonstrates vitamin E’s potential as an excellent alternative treatment for chronic insomnia disorder that improves sleep quality and reduces sedative drug use.