Sleep and weight gain
For years doctors and health workers have been espousing the importance of getting enough sleep to maximise mental and physical performance and now it also appears not getting enough sleep can adversely affect our weight.
As the prevalence of overweight and obese individuals in modern society has increased, there has also been a concurrent decline in sleep duration. When dealing with two very different changes over a period of time, it’s important to ask the question; is it the lack of sleep causing the weight gain or the excessive weight causing the lack of sleep?
The chicken or the egg?
Longitudinal studies have suggested it is sleep deprivation that is the contributing factor for weight gain, effects were seen in adults at sleep durations of less than 7 hours per night. However it is not only adults that are at risk; children who have less than 10 hours sleep a night are more likely to develop weight issues later on in adolescence and adulthood. It should also be noted that sleep duration of greater than 9 hours per night in adults has also been shown to lead to weight gain (however not to the same extent as sleep deprivation). This question of too much sleep seems to need further investigation.
So what are the possible causes of weight gain?
- More time awake equals more time to eat
- We may eat more to try to recover energy lost due to sleep deprivation
- Sleep deprivation leads to lethargy and a reduction in physical activity; planned, incidental and involuntary (such as fidgeting)
- Hunger regulating hormones are influenced by sleep
o Leptin suppresses appetite and is decreased during sleep deprivation
o Ghrelin stimulates appetite and is increased during sleep deprivation
Do we sleep less than our ancestors?
Before the invention of electricity people tended to retire and rise with the sun; so they were more in tune with their bodies’ natural circadian rhythm. Nowadays with around the clock electronic entertainment at our fingertips, increased shift work, longer commuting time and more two income households, it is believed we have more people sleeping less than 7 hours per night than ever before.
How much sleep should we get?
Research into sleep and weight gain is still in its infancy, but aiming for 7-8 hours sleep per night may be a good way of helping to maintain a healthy weight and you’ll gain other health benefits such as feeling more alert during the day and being in a better mood.
Tips for a Good Night’s Sleep:
- Be consistent - set your sleep cycles by having regular times for going to bed and getting up.
- Exercise - often our minds are tired but our bodies are not. Try to exercise a minimum of 30 minutes a day.
- Avoid stimulants such as caffeine, nicotine, and alcohol which keep you awake or rob you of quality deep sleep.
- Unwind from the stresses of the day before retiring for sleep. Try a warm bath, reading or relaxing to music, and make it part of your bedtime ritual.
- Your bedroom is a sleep zone. Remove unnecessary distractions like TV’s and radios, and ensure the room is a comfortable temperature. Never bring work into your bedroom.
- Upon waking expose your body to bright lights or sunshine as this helps stimulate hormones that cause us to wake and feel alert. Likewise avoid bright lights just before you prepare for sleep.
- If you regularly have sleep problems visit your local GP who may be able to help you or refer you to a sleep specialist.
- Melatonin is a hormone secreted by the pineal gland, which is believed to promote sleepiness. It is also present in some foods and it has been suggested eating foods containing melatonin, such as oats, corn, rice, bananas and cherries may help with sleep.