|Since the natural melatonin production decreases as we age, it is (unfortunately) possible that younger women wouldn't see the same benefits as the >56 year-old subjects of the study at hand.|
In said study, Anne Kristine Amstrup and colleagues tested whether there's anything to the rumors that have it that "melatonin [has] a positive effect on body weight and energy metabolism" (Amstrup. 2015). As the researchers rightly point out, previous "evidence for this relies mainly on animal models" (ibid). It was thus about time for someone to "determine the effects of melatonin on body composition, lipid and glucose metabolism in humans" (ibid).
In this case, said human beings were 81 post-menopausal Caucasian women (aged 56-73 years) diagnosed with osteopenia (T-score between -1 and -2.5 in the hip or spine). The Danish scientists randomized the women to receive
- either melatonin, at a dosage of 1 or 3 mg per day, or
- an identically looking placebo nightly (timing matters!)
"To assess body composition, we used a whole body scan by dual X-ray absorptiometry (DXA, Hologic Inc., Waltham, MA, USA). We performed scans at baseline and after one year of treatment. Assessments included total and subtotal body mass (g), lean mass (g), fat mass (g) and percentages of body fat. We calculated body mass index (BMI) as body weight (kg) divided by height² (in metres)" (Amstrup. 2015).... and a detailed analysis of the blood of their subjects, the body composition and biochemical analyses were similarly thorough as the randomization protocol which was performed by an external pharmacy (Skanderborg Pharmacy).
|Figure 1: Changes in body composition (left) and adiponectin (right) in response to 1-3mg of melatonin taken at night over a 12-months period without further exercise or diet intervention (Amstrup. 2015).|
|Melatonin As Potent as Letrozole in Inhibiting Aromatization | more|
|Figure 2: Rodent studies also show that melatonin supplementation prolongs the lifespan of the average mouse (Pierpaoli. 1994) and rat (see data in graph) significantly (Oaknin-Bendahan. 1995).|
- Amstrup, et al. "Reduced fat mass and increased lean mass in response to one year of melatonin treatment in postmenopausal women: A randomized placebo controlled trial." Clinical Endocrinology (2015): Accepted article.
- Leonardo-Mendonça RC, et al. "The benefits of four weeks of melatonin treatment on circadian patterns in resistance-trained athletes." Chronobiol Int. 11 (2015): 1-10.
- Oaknin-Bendahan, Sol, et al. "Effects of long-term administration of melatonin and a putative antagonist on the ageing rat." Neuroreport 6.5 (1995): 785-788.
- Okatani, Yuji, Nobuyuki Morioka, and Akihiko Wakatsuki. "Changes in nocturnal melatonin secretion in perimenopausal women: correlation with endogenous estrogen concentrations." Journal of pineal research 28.2 (2000): 111-118.
- Prunet-Marcassus, Benedicte, et al. "Melatonin reduces body weight gain in Sprague Dawley rats with diet-induced obesity." Endocrinology 144.12 (2003): 5347-5352.
- Rasmussen, Dennis D., et al. "Daily melatonin administration at middle age suppresses male rate visceral fat, plasma leptin, and plasma insulin to youthful levels." Endocrinology 140.2 (1999): 1009-1012.
- Wolden-Hanson, T., et al. "Daily Melatonin Administration to Middle-Aged Male Rats Suppresses Body Weight, Intraabdominal Adiposity, and Plasma Leptin and Insulin Independent of Food Intake and Total Body Fat 1." Endocrinology 141.2 (2000): 487-497.