Aim for at least seven hours of sleep to rev up your weight loss efforts.
Weight loss scale
Credit: Lee Harrelson

Studies have found a strong link between the amount of "shut eye" and the risk of becoming obese. Those who sleep four hours or less are 70% more likely to be obese. Those who sleep 5 hours have a 50% greater risk, and those who sleep 6 hours have a 20% greater risk. The recommendation? Seven or more hours of sleep for everyone.

It seems confusing that more sleep might help prevent obesity, especially since your body burns fewer calories resting than it does when moving. True, but these studies have found that chronic sleep deprivation affects how the brain is wired for appetite. Lack of sleep lowers leptin, a protein that suppresses appetite and affects how the brain determines when it has had enough food. Sleep deprivation also appears to raise the levels of grehlin, a hormone that makes you want to eat more. Lack of sleep also affects your ability to make clear decisions, too. It's easier to grab a quick, junk food fix than take the time to plan and prepare a healthy meal or snack when you'e tired. Put all this together, and lack of sleep can pack a powerful punch to your weight loss efforts. So when you plan your exercise for the week, plan your sleep schedule, too.

Tammy Beasley, RD, CSSD, CEDRD is a registered, licensed dietitian, spinning instructor, and certified specialist in sports nutrition and eating disorders. She is the author of Rev It Up-The Lifestyle Diet That Puts You In The Driver's Seat.