Sleep Less, Gain Weight?
How does getting less sleep increase the risk of Obesity and Type 2 Diabetes?
One explanation is the up-regulation of appetite stimulating hormones. Appetite is regulated by hormones. There are two major hormones in the body that regulate appetite: leptin and ghrelin. Leptin is secreted from the body's fat cells. Leptin inhibits food intake and increases energy expenditure. Ghrelin is mainly secreted in the stomach. Ghrelin increases hunger levels and food intake and decreases energy expenditure.
Researchers have found people with shorter sleeping durations have increased circulating ghrelin, increased food intake, decreased energy expenditure, and increased weight gain. Leptin levels were also lower compared to people who had adequate amounts of sleep. These results indicate inadequate sleep may influence the hormones for satiety and hunger in ways that promote overeating, especially at night.
Sleep deprivation also causes changes in insulin, cortisol, and growth hormone levels in the body. Cortisol and growth hormone secretion increases with sleep deprivation. The increase in cortisol and growth hormones can cause an increase in waist circumference and contribute to weight gain. Cortisol and growth hormone may be a risk factor for insulin resistance.
Your body produces a hormone called insulin after each meal in order to help break down and absorb the food you eat. Insulin is important because it signals the body's cells to uptake glucose in the bloodstream and inhibits glucose production in the liver. Increased insulin resistance is a major risk factors for people diagnosed with Type 2 Diabetes.
Sleep Deprivation and Diabetes
Several prospective studies have examined the association between sleep duration and weight related health problems. Researchers from the Nurses Health Study found an increased risk for women developing diabetes over a 10 year period who slept for 5 hours or less a night. These women had more resistance to insulin, a symptom of diabetes, than women who slept for 7-8 hours a night.
In a male-only study, researchers from the Massachusetts Male Aging Study found men who slept 6 hours or less had twice the risk for developing diabetes.
Sleep deprivation not only has an effect on adult men and women, but it can have an impact on children's health as well. Researchers from the Drexel University College of Medicine reported children with a shorter sleep duration have a higher rate of insulin resistance, a precursor for diabetes, than children with normal sleep durations.
Why Not Sleep?
If sleep deprivation is so bad for our health, why do we choose to sleep less?
There are actually a lot reasons why we don't get adequate sleep:
-Personal Choice: Many people choose to stay up late to socialize, watch TV, browse the internet, etc.
-Work: Workloads have drastically increased in the past 40 years. Employees often take their work home with them to meet company expectations. Shift workers may also have a disrupted sleep pattern from abnormal sleeping hours.
-Sleep Disorders: Sleep apnea and snoring may disrupt a person's sleep.
-Medications: Side effects of some prescription drugs may affect sleep onset or duration.
-Sleeping Environment: Bedroom temperature, mattress quality, noise, and darkness level all affect the way and amount we sleep.
-Parenting: Young children frequently wake in the middle of the night for feeding.
How Much Sleep is Enough?
The exact reasons for why we need sleep are not completely understood. Sleep may be necessary for the brain's memory, energy balance, or to process the day's information. It has been found that a lack of sleep impairs memory function, affects our mood, and reduces our cognitive abilities. According to the National Sleep Foundation, 74 % of American adults experience a sleeping problem a few nights a week, 39% get less than seven hours of sleep, and 37% of people polled are so tired during the day that it affects their daily tasks.5
The amount of sleep necessary to avoid the symptoms of sleep deprivations varies from person to person. Most experts consider seven to nine hour of sleep to be the normal range, but some people are able to function on less without any effect on performance.
Sleep Needs Over the Life Cycle According to the National Sleep FoundationInfants/Babies
0-2 months: 10.5 - 18.5 hours/day
2 - 12 months: 14 - 15 hours/day Toddlers/Children
12-18 months: 13 - 15 hours/day
18 months - 3 years: 12 - 14 hours/day
3-5 years: 11 - 13 hours/day
5 - 12 years: 9 - 11 hours/day Adolescents
: 8.5 - 9.5 hours/day Adults
: 7 - 9 hours/day
Tips for Better Sleep According to the National Sleep Foundation:
-Exercise regularly - regular exercise has been shown aid in a sounder sleep. But finish exercising at least three hours or more before bed for a restful night.
-Maintain a regular bed and wake time schedule, including weekends.
-Establish a relaxing bedtime routine - soak in a bath, read, or listen to soothing music.
-Create a healthy sleep environment - find out which bedroom conditions are most comfortable for you. A cool, dark, quiet room will decrease sleep interruptions for a better night's sleep.
-Sleep on a comfortable mattress with supportive pillows - this is essential for a sleep.
-Keep the television, work, computer, and other distracting things out of the bedroom.
-Avoid caffeine in the late afternoon/evening and before bedtime - coffee, tea, and soft drinks which have caffeine may interfere with getting enough sleep.
Created by: Brian Feldmeier, Dietetic Intern
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