The word has been out for a while that lack of sleep can mess with weight loss and weight management, but get this: According to a small study published in the Annals of Internal Medicine, when dieters in the study got a full night’s sleep, they lost the same amount of weight as when they slept less. When dieters got adequate sleep, however, more than one half of the weight they lost was fat. When they cut back on their sleep, only one fourth of their weight loss came from fat.
Participants were placed on an individualized, balanced diet, with calories restricted to 90% of what each person needed to maintain his or her weight without exercise. Each participant was studied twice: once for 14 days in the laboratory with an 8.5-hour period set aside for sleep, and once for 14 days with only 5.5 hours for sleep. Cutting back on sleep appears to compromise efforts to lose fat through dieting.
Getting adequate sleep also helped control the dieters’ hunger. When sleep was restricted, dieters produced higher levels of ghrelin, a hormone that triggers hunger and reduces energy expenditure. Higher ghrelin levels have been shown to reduce energy expenditure, stimulate hunger and food intake, and promote retention of fat.
Aside from lack of sleep, rumor also has it that by not eating after a certain time of night, you’ll lose weight. However, it’s not necessarily the time cut-off that will rid you of the pounds. Calories count. Whether you eat them at 9 a.m. or 9 p.m., a calorie is still a calorie. However, if you give yourself fewer chewing hours, you’ll likely take in fewer calories and have more active hours to burn them off. This is especially helpful for late-night snackers who reach for the chips and cookies late night. If this sounds familiar, a cut-off time for eating might be helpful to you.
A recent global survey of worldwide sleep patterns from the Philips Center for Health and Well-being shows that Americans are some of the most sleep-deprived people in the world. So, what can you do about it?
Now is your chance to learn which foods to eat and which to steer clear of for a good night’s sleep.
Should you reach for tryptophan-rich foods?
The hormone serotonin is an important factor in triggering sleep. Since our nerve cells use the amino acid tryptophan to make serotonin, much attention has been given to the role of tryptophan (and tryptophan-containing foods) in promoting sleep. Studies of tryptophan’s impact on sleep have found that it is only one phase of sleep – the falling asleep part – that is enhanced by tryptophan. Other aspects of sleep, such as the amount of deep-sleep reached during the night, may actually be harmed by supplemental tryptophan.
Many animal foods are relatively high in tryptophan and might sound like logical candidates for improving sleep. However, these same animal foods are also fairly high in other amino acids (like tyrosine) that could be used to produce other substances (like adrenalin) that would usually decrease with the onset of sleep. In summary, trying to up your serotonin by increasing your evening intake of high-tryptophan foods as a way to improve your sleep is not recommended.
Our serotonin levels respond to other aspects of our diet, however, and one of those aspects is carbohydrate intake. Eating foods higher in carbohydrates raises our blood insulin level. This is because carbohydrates are digested relatively quickly and raise our blood sugar level more quickly than proteins or fats. Along with this increased insulin level there is an increased transport of amino acids into our brain, including tryptophan. More brain tryptophan leads to more brain production of serotonin and increased likelihood of sleep onset.
Put down the burger and chips!
Sometimes we rationalize and think that a big meal will actually help us get to sleep by exhausting our body and having it slow down from exhaustion as it tries to digest the large meal. It’s tempting logic, but research evidence points in the opposite direction. A large meal does the opposite of slowing our body down. It asks our circulatory system to move more blood to our digestive tract. It asks our stomach to secrete more gastric acid. It asks our pancreas to become more active and produce digestive enzymes. In short, a large meal does anything but relax us. Research also shows that people who often eat high-fat foods not only gain weight, they also experience a disruption of their sleep cycles.
Beware of hidden caffeine
It’s no surprise that an evening cup of coffee might disrupt your sleep. Even moderate caffeine can cause sleep disturbances, but don’t forget about less obvious caffeine sources, like chocolate, cola, tea and decaffeinated coffee. For better sleep, cut down your caffeine consumption and avoid caffeine in the hours before going to bed.
With respect to sleep, if you are going to eat a snack 1-2 hours before bed, a small carbohydrate-based snack that includes some protein and some fat would make the most sense. Snacks to get you snoozing might include: 100% whole grain crackers with a schmear of almond butter.
About This Author
Joanna Dolgoff, M.D. is a Pediatrician, Child Obesity Expert, and Author of Red Light, Green Light, Eat Right (Rodale, 2009). Dr. Dolgoff’s child and adolescent weight loss program (http://www.DrDolgoff.com) has been featured on WABC News, WNBC News, Fox 5 Morning Show, My9 News, and WPIX News. She has also filmed pieces with The Today Show and Extra, is an official blogger for the Huffington Post, and is the official doctor for Camp Shane, the nation’s largest weight loss camp. Children from 45 different states are losing weight with Dr. Dolgoff’s online weight loss program (http://www.DrDolgoff.com).
Dr. Dolgoff attended Princeton University and the NYU School of Medicine and completed her Pediatric Residency at the Columbia Presbyterian Children’s Hospital of New York. She is a Board-Certified Fellow of the American Academy of Pediatrics and a former certified fitness instructor. Dr. Dolgoff resides in Roslyn, NY with her husband and two children, ages 4 and 7.