If you thought that obesity was mostly related to diet and exercise, you may want to think again. New research from Wake Forest University School of Medicine shows that for people under 40, not getting enough sleep at night can cause larger amounts of fat to accumulate around the organs, a dangerous form of fat accumulation.

Visceral Fat Accumulation

The study showed that in people under 40, getting less than 5 hours of sleep a night was related to increases in visceral fat — that is, fat that accumulates around internal organs. Visceral fat is one of the reasons many people have big bellies, and is linked to a greater risk of obesity, heart disease, diabetes, and even some types of cancer, than fat accumulation in other areas such as the thighs and buttocks. In addition, visceral fat, the fat located deeper in the abdomen around the organs, is more dangerous than the more visible fat located just under the skin on the abdomen. These fat cells can produce hormones that may disrupt your health, such as excess estrogen after menopause, or hormones that cause your body to become insulin resistant.

Getting Too Much Sleep or Not Enough Are Both Unhealthy

The research showed that inadequate sleep can result in increases in visceral fat, but the opposite is also true — too much sleep can also lead to an increase in visceral fat, though to a lesser degree. Getting more than 8 hours of sleep a night can lead to fat increase, but the effects are still not as severe as in individuals who get less than 5 hours of sleep a night. In general, people should aim for 7-8 hours of sleep every night. For young people in various stages of college, career, marriage and child-bearing, getting adequate sleep may be difficult, but essential. Minority groups seemed to be the most greatly affected by not enough sleep, though the study did not investigate in depth the reasons this might be the case.

It was not clear why people over 40 did not seem to be affected in the same way.

Reducing Visceral Fat

In addition to getting adequate sleep every night, there are other things you can do to reduce visceral fat. Luckily, excess visceral fat responds well to a healthy exercise and diet regimen. Daily exercise and a diet that avoids saturated fats and refined carbohydrates can have a significant effect on belly fat. Regular moderate-intensity exercise will tone your body and contribute to your overall health, and you may find that your belly fat is the first to go. Strength training may also help to burn excess belly fat.

If you are concerned about a growing midsection, talk to your doctor or health-care practitioner to see what adjustments in your lifestyle can help to reduce abdominal fat.