ou have been wondering what's wrong with your body lately.
You have stuck to your diet.
You work out fairly regularly.
You don't smoke or drink.
But -- horrors! -- you have put on a few kilos.
Hmmmm! Let's see.
Does lack of sleep figure among your lifestyle habits?
If it does, it could be the reason for the new statistics on the weighing scale.
Studies published on December 6 in Washington say losing sleep could increase the levels of the hormones associated with appetite and eating behaviour.
A team led by Eve Van Cauter, professor of medicine, University of Chicago, studied 12 healthy men in their early 20s. They measured circulating levels of leptin (this hormone tells the brain there is no need for more food) and ghrelin (this triggers hunger) before the study and after two nights of only four hours of sleep and after two nights of 10 hours of sleep.
Dr Emmanuel Mignot of Stanford University, California, led a team that examined 1,000 people in the Wisconsin Sleep Cohort Study. They measured each person's sleep habits, the sleep pattern on the night before the examination and their leptin and ghrelin levels.
Here are some findings:
1. According to the first study, there was an 18 percent reduction in leptin, and a 28 percent increase in ghrelin.
2. After four hours of sleep, the ratio of ghrelin rose to 71 percent, when compared to the level it was at after a nine-hour sleep schedule.
3. Interestingly, the young men who slept fewer hours displayed a fetish for candy, cookies and cake over fruit, vegetables or dairy products.
'We don't yet know why the food choice would shift,' Eve Van Cauter, professor of medicine, University of Chicago, said on cnn.com.
She adds, 'Since the brain is fuelled by glucose, we suspect it seeks simple carbohydrates when distressed by lack of sleep.'
4. The second study, which used the Body Mass Index as an indicator, found that the less people sleep, the more they weigh.
5. Those who slept five hours or less per night had, on average, 14.9 percent more ghrelin and 15.5 percent lower leptin levels than those who slept eight hours a night.
6. The researchers found that sleep is relaced by added calories.
'Our results demonstrate an important relationship between sleep and metabolic hormones,' the researchers wrote in the Public Library of Science Medicine journal.
Samreedhi Sharma, nutritionist and fitness expert [chat with her on December 13 only on rediff.com], adds, "What most people don't realise is that lack of sleep also leads to water retention, leading to those extra kilos on the weighing scale. Your metabolism also slows down, which means you take that much longer to lose weight."
The answer is simple: If you want to lose weight, catch up on those zzzzzs!
Sleep well. Sweet dreams!
Illustration: Uttam Ghosh
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