Our ability to lose weight is closely linked to how well and how long we sleep. People who sleep less weigh more than people who sleep longer (as in sleep adequately, around 6-8 hours). Weight gain and sleep—it’s an inversely proportional relationship, and there are studies that point to this fact. Every time you don’t sleep well or sleep too late you feel the effects right away—bloating, irritation, headaches—and long-term uhealthy lifestyle diseases—diabetes, blood pressure and cardiovascular diseases—kick in too.

Sleep right: Don’t scrimp on sleep if you want to stay in good shape.

There are many reasons why you should worry about not sleeping well or on time, the main one being lack of awareness. An unknown enemy is more dangerous than a known one. We do understand that not exercising or eating too much can harm us but we haven’t fully learnt to appreciate the downside of not sleeping well. Yet lack of knowledge about good sleeping habits doesn’t protect us from its ill-effects.

One of the first effects is on your stomach. If you are sleeping less than is good for your body, it will lead to an interference with the absorption and assimilation of nutrients.

Ever noticed how the affluent are victims of vitamin D, B12 deficiencies? They have enough to eat, have access to trainers and gyms and yet are victims of vitamin deficiency that the body requires in really minuscule amounts. There’s an unwritten law—the richer you get, the more you party, the later you sleep. And the written law is—the later you sleep, the poorer your vitamin stores get.

The other damning effect of the lack of adequate sleep is the toll it takes on your growth hormone. When the secretion of growth hormone suffers, the repair and restoration work in our body comes to a full stop. When we sleep our body goes into a “work in progress" mode. If, however, we don’t allow the body to finish its job then the inconvenience just doesn’t end; this leads the body to become more vulnerable to lifestyle diseases. Diabetes is closely linked to lack of sleep. The more disturbed our sleep, the more disturbed our blood sugar level, the more vulnerable we are to developing full-fledged diabetes.

In terms of weight loss, our inability to sleep well disturbs our appetite, making us eat more in the night and less in the day. Now you don’t need a nutritionist to tell you this, but the less you eat in the day, the higher your chances of overeating in the night and the more you overeat in the night, the more body fat you will carry—or to put it simply, the fatter you will get.

So just follow a few basic rules:

• Sleep at the same time every night or at least on most days. And yes, sleep on the same day you wake up and not after midnight

• Keep a gap of two-and-a-half hours between your last meal and bedtime

• Keep your bedroom, or at least your bed, free of the TV, laptop and BlackBerry

• Avoid caffeine post-sunset

• If you use an air conditioner at night, make sure the windows are opened in the day to allow for good “airing" of your bedroom

• Waking up more tired than when you slept is a big warning sign—start cleaning up your food and exercise habits

• Sleeping in the car doesn’t make up for staying up late in the night—learn that by heart

• Oversleeping is just as harmful, so don’t overdo it.

This is the third in a four-part series by nutritionist Rujuta Diwekar. Her new book Women and the Weight Loss Tamasha (Westland, 200) will be out in January.

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