New York: Insomnia goes hand in hand with poor health, including weight gain and even obesity, say a study done by an Indian-American psychiatrist.
Sarosh Motivala, assistant psychiatry professor at Semel Institute, University of California Los Angeles (UCLA) and colleagues looked at two hormones that regulate the body's energy balance and our hunger pangs.
The study, based on 38 male participants divided into two groups - 14 insomnia sufferers and 24 healthy subjects, found that chronic insomnia disrupts one of these two hormones.
To date, no study has evaluated nocturnal levels of the two hormones, ghrelin and leptin, in primary insomnia patients.
Ghrelin, a peptide secreted by the stomach, stimulates appetite and increases before meals. Leptin, which affects body weight and is secreted primarily by fat cells, signals the hypothalamus (in the brain) regarding the degree of fat storage.
Decreased leptin tells the body there is a calorie shortage and promotes hunger, while increased levels promote energy expenditure.
Researchers compared healthy sleepers with those suffering from chronic insomnia and measured the levels of the two hormones at various times throughout the night.
They found that while leptin levels averaged out over the night to be roughly the same between the two groups, levels of ghrelin were 30 percent lower in insomnia sufferers.
On the face of it, a decreased level of ghrelin would seem to inhibit weight gain; it is an increase in ghrelin, after all, that stimulates appetite.
But Motivala compared his findings with other, earlier studies on sleep deprivation and speculates that a switch may occur during the day.
Sleep loss leads to increased ghrelin and decreased leptin, a "double whammy" that stimulates appetite. Motivala is currently working on a study to examine this switch, said an UCLA release.
Motivala did his schooling in Mumbai, where he was born and did his BA in psychology in 1997 and clinical internship in behavioural medicine from UCLA in 2001.
The study is slated for publication in the May issue of 'Psychoneuroendocrinology'.