By Dr. Mallika Marshall

BOSTON (CBS) – It’s estimated that up to 11 percent of kids ages 4 to 17 are diagnosed with attention deficit hyperactivity disorder (ADHD), but could your child just be sleep deprived?

A recent analysis found that 75 percent of children and adults with ADHD also have disruptions in their biological clocks, causing them to fall asleep later and sleep less. But it is unclear what comes first, if sleeplessness contributes to ADHD or if ADHD causes sleep problems.

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While more research is needed, experts say there may be a significant number of kids and adults diagnosed with ADHD who could benefit from better sleep.

TAKE A BREAK FROM DIETING

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If you’re on a diet, you may be afraid to cheat, but new research suggests that taking a break while dieting may bring greater success.

Scientists in Australia looked at several dozen obese men who were placed on a calorie-restricted diet for 16 weeks. They found that the men who took 2-week breaks from dieting lost more weight than those who dieted continuously and were more likely to maintain their weight loss six months later.

This was a small study but the theory is when you restrict your calories, your resting metabolism slows down, making it harder to lose more weight. If, however, you alternate periods of relative fasting with normal calorie intake, you might be able to avoid this metabolism sabotage.

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That doesn’t meant that you can eat whatever you want during the two weeks of diet freedom.  In the study, the participants ate enough calories to maintain weight but not to gain it.

Dr. Mallika Marshall