How Much Do You Need to Sleep Every Night to Prevent Weight Gain?

Researchers found that among adults younger than 40, those who typically slept for five hours or less each night had a greater accumulation of belly fat over the next five years.

But those who logged eight hours or more in bed each night also showed a bigger fat gain, although it was less substantial than that seen in “short sleepers.”

On average, short sleepers showed a 32 percent gain in visceral fat, versus a 13 percent gain among those who slept six or seven hours per night, and a 22 percent increase among men and women who got at least eight hours of sleep each night.

A similar pattern was seen with superficial abdominal fat. Even when the researchers considered factors like calorie intake, exercise habits, education and smoking, sleep duration itself remained linked to abdominal-fat gain.

The study does not prove that too little or too much sleep directly leads to excess fat gain. But the findings support and extend those of other studies linking sleep duration — particularly a lack of sleep — to weight gain and even to higher risks of diabetes and heart disease.

Sources:

  Reuters March 1, 2010

  Sleep March 1, 2010

How Much Do You Need to Sleep Every Night to Prevent Weight Gain?.

Read This Shocking Vitamin D Report or You’ll Kick Yourself for the Next Decade

The British Medical Journal has published a remarkable paper confirming that low vitamin D levels obtained in the past are a risk factor for developing colon cancer in the future.

But the study contained an even more significant finding — as Dr. Cannell’s site has reported before, vitamin A, even in relatively low amounts, can thwart vitamin D’s association with reduced rates of colon cancer.

This is the largest study to date showing vitamin A blocks vitamin D’s effect.

Hidden on page eight of the paper was one sentence and a small table, showing that the benefits of vitamin D are almost entirely negated in those with the highest vitamin A (retinol) intake.

And the retinol intake did not have to be that high — only about 3,000 IU/day. Young autistic children often take 3,500 IU of retinol a day in their powdered multivitamins, which doesn’t count any additional vitamin A given in high single doses.

The finding explains some of the anomalies in other papers on vitamin D and cancer — similar studies sometimes have widely different results. This may be because the effect of vitamin A was not taken into account. In some countries, cod liver oil, which contains vitamin A, is commonly used as a vitamin D supplement, and in others it is used more rarely, causing differences in the results.

Sources:

  The Natural Advocate February 28, 2010

  Vitamin D Council

  British Medical Journal, BMJ 2010;340:b5500

Read This Shocking Vitamin D Report or You’ll Kick Yourself for the Next Decade.