How will losing weight help me sleep better?

DEAR DOCTOR K:

I’m overweight. My doctor told me, among other things, that losing weight would help me sleep better. What’s the connection?

DEAR READER:

It’s true. Losing weight, especially in your belly, improves the quality of sleep if you are overweight or obese.

A number of studies have shown this to be true. In one study, researchers followed people who lost an average of 15 pounds over six months. About 15 percent of the weight loss was in their bellies. The weight loss was associated with improved sleep quality.

What’s the connection? For one thing, excess body weight, especially in the neck, increases the likelihood of developing obstructive sleep apnea. This condition occurs when your airway becomes blocked, either completely or partially, while you sleep. It causes you to stop breathing, sometimes hundreds of times per night. Not surprisingly, sleep apnea disrupts your sleep. It also puts you at risk for other conditions, including stroke and high blood pressure. So, one possibility is that weight loss reduces the risk of sleep apnea and improves sleep quality.

Another likely reason that weight loss leads to improved sleep is linked to diabetes. Weight loss reduces your risk of getting diabetes. And diabetes increases your risk of getting restless leg syndrome, which disrupts your sleep. Weight reduction might also reduce the frequency of those sleep disorders, thereby improving sleep quality.

We don’t yet know why losing belly fat in particular is associated with improved sleep. We do know, however, that certain belly fat, called visceral fat, is associated with heart disease, dementia, breast and colon cancers, and asthma. Probably, this is because belly fat cells produce hormones that have negative health effects.

Losing weight in the belly seems a logical way to improve not only sleep but also overall health. Unfortunately, it’s difficult to target weight loss to the belly alone. But generally, if you lose weight, some of this will come from belly fat.

The answer to losing weight, improving sleep and losing belly fat winds up being overall weight loss through good old-fashioned exercise and a healthy diet. Take it slowly. Aim for 150 minutes of moderate-intensity physical activity (like swimming or brisk walking) each week. You don’t have to do five 30-minute workouts. More frequent but shorter exercise sessions, such as three 10-minute brisk walks instead of one 30-minute walk, will have the same impact.

You also need to cut back on calories. The lasting effects of combining exercise and weight loss will go far beyond improving your night’s sleep and well into a healthy future.

I once encouraged a patient to join a group program for losing weight. I explained to her all of the health benefits of losing weight — the lower risk of heart disease, stroke, diabetes, breast and several other forms of cancer. She was dubious. After she lost 25 pounds, she told me: “I’m still not convinced this is good for my health. But I finally like the way I look. Plus, I’m sleeping like a baby.”