The stereotype is that the lazy, oversleeping person becomes the fat slob. But it looks like the opposite may be true.

If a new study published in the Annals of Internal Medicine is right, then not getting enough sleep is what may be making you fatter.

According to this study, if you don’t get enough sleep there is a harmful response by your fat cells. Lack of sleep, reduces fat cells ability to respond to insulin by about 30 percent.

I have written before about sleep, the lack of it and ways to try to improve it. I have sleep apnea and have never been a good sleeper. I stay up too late watching TV, reading or writing. And I have gained 25 pounds that I don’t need over the past five years.

The research shows that over the long-term, those fat cells not responding properly could increase my chances for Type 2 diabetes (which runs in my family), as well as fatty liver disease and even more weight gain.

So, what do places like the Center for Sleep and Wake Disorders recommend that we do about sleep?

Get seven to nine hours per night.

The people tested in the study got 4 nights of 8 and a half hours of sleep and then the next month they were monitored again with 4 nights of only 4 and a half hours of sleep allowed. Four nights doesn’t seem like enough time to get any real changes, but the fat cells responded significantly to the loss of sleep – which surprised the researchers too.

It is worth noting that the researchers feel that the fat cells of healthy young people would probably return to normal when their sleep patterns returned to normal. But I am not young and the effect over a lifetime might not be reversible.

I would say that what you eat, how much you eat and how much exercise you get are still the major factors for your health and weight. But I am also being convinced that getting good sleep is pretty high on the list.

If you don’t want your body to store more of what you eat as fat, you had better get those full nights of sleep. Even a half-hour a night, seems to have an effect.