Sleep Hormone Loss Raises Diabetes Risk

Type 2 diabetes risk appears to rise as melatonin secretion drops in women

(RxWiki News) Melatonin is key to regulating your wake-sleep cycle, and a lack of this hormone can affect your health in many ways. New research suggests it may even raise your risk of diabetes.

People take melatonin supplements to treat a number of ailments, including Alzheimer’s disease, depression, migraine headaches (IBS), bone loss (osteoporosis), and cancer among many others.

Recent research found that a lack of the so-called “sleep hormone” may also be linked with a higher risk of developing type 2 diabetes. The findings showed that people with the lowest levels of melatonin had more than double the risk of type 2 diabetes than those with the highest levels.

"Find out how melatonin levels can affect your health."

Ciaran J. McMullan, MD, of Brigham and Women's Hospital in Boston, led the investigation to follow up on previous research suggesting that melatonin may play a role in glucose metabolism. Glucose metabolism is the process of converting glucose (blood sugar) into energy for your body’s cells.

Dr. McMullan and her team analyzed data on 370 women who developed type 2 diabetes from 2000 to 2012 and matched them with 370 controls. At the start of the study in 2000, participants were identified as not having diabetes based on urine and blood tests.

Over the course of the study, secretion of melatonin varied widely among subjects. To measure this, scientists looked at the ratio of melatonin to creatinine in the urine. Creatinine is a common waste product made by your muscle metabolism. The kidneys filter out extra creatinine through urine.  

Researchers considered a high urinary ratio of melatonin to creatinine to be 67.0 ng/mg and a low level to be 14.4 ng/mg. Participants in the lowest category of urinary ratio of melatonin to creatinine had 2.2 times higher odds of developing type 2 diabetes compared to participants in the highest category.

“It is interesting to postulate from these data, in combination with prior literature, whether there is a causal role for reduced melatonin secretion in diabetes risk,” concluded the authors.

Dr. McMullan and her colleagues believe further studies are needed to determine whether increasing melatonin levels can increase insulin sensitivity and decrease the incidence of type 2 diabetes. Patients can increase melatonin levels through prolonged nighttime dark exposure or by taking supplements.

“Melatonin receptors have been found throughout the body in many tissues including pancreatic islet cells, reflecting the widespread effects of melatonin on physiological functions such as energy metabolism and the regulation of body weight,” the authors wrote. “Loss-of-function mutations in the melatonin receptor are associated with insulin resistance and type 2 diabetes. Additionally, in a cross-sectional analysis of persons without diabetes, lower nocturnal melatonin secretion was associated with increased insulin resistance.”

Patients should not take melatonin or any other dietary supplement without first consulting with their doctor.

The study was published in the April 3 issue of the Journal of the American Medical Association. This work was supported by grants from the National Institutes of Health. Collaborating researcher Dr. Hu reported serving as a consultant to Novo Nordisk and receiving grants from Merck and the Walnut Commission.

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Review Date: 
April 2, 2013