Food possesses significant impact upon our health and overeating is linked with numerous long-term health risks. There are dozens of researches dealing with sleep problems as a factor that influences people’s eating behavior. In this article I will reveal the basic mechanisms of the sleep effect upon eating habits and vice versa.
Eating behavior is linked with serious chronic health problems (obesity, diabetes, heart diseases) and logically is a treatment goal, as well as a target for prevention and prophylaxis of these conditions. Sleep is one of the main factors acting upon food consumption.
Food intake is driven by homeostatic (i.e. biological), emotional, cognitive, social and environmental factors. Sleep disorders influence the way we eat, and usually sleep deprivation leads to increased food intake, as the body tries to compensate the deficit of night’s energy as a result of the increased wakefulness and the related increase in energy consumption.
Several researches have been made in support of this statement that show the daily intake of food is increased with at least 20% after sleep restriction, but the participants doesn’t perceive consciously this change in eating. Taken together, all these results indicate that sleep deprivation affects the size of the serving, no matter the type of food. Or in other words said, overeating after a period of lack of sleep has a biological basis in the pursuit of the organism to maintain homeostasis.
Other researches show that reduced sleeping leads not only to increased amount of the consumed meals, but also a preferential consumption of more caloric food which has its neurological explanation, namely: increased activation of the brain regions associated with taste and the satisfaction feeling is seen on functional MRI after sleep restriction.
Researches in pediatric patients confirm the above results. The study of McDermott et al. (2008) shows newborns who has impaired sleep time up to 6 months are more prone to have irregular food intake in the age between 2 and 4. More actual studies (Tatone et al., 2012) also show this link and demonstrate association between the short-term sleep and the decreased intake of fruits and vegetables. The shortened sleep mode is also associated with irregular feeding and/or too fast consumption of the food.
Sleep disturbances lead to hormonal misbalance. Except for all known hormones (glucocorticoids, insulin etc.), the recently found hormones leptin and ghrelin are also affected. Leptin is adipocytokine that gives impulses for satiety to the center of appetite control in the hypothalamus. (Ahima, A.S. et al, 2000). On the contrary, ghrelin is appetite stimulating hormone, sending signals from the stomach to the brain in order to induce appetite rise. (Van Der Lely et al. 2004). Researches show that the ratio between leptin and ghrelin is quite different in people who sleep insufficiently compared to those who have enough sleep.
Low levels of leptin (low levels of the satiety signals respectively) are seen in the so called “short sleepers” (people who don’t need so much sleep), and in those which are deliberately restricted to sleep (Chaput et al., 2007; Hart et al., 2013; Taheri et al., 2004). This means sleep deprivation acts upon leptin bioavailability in order the occurred energy misbalance to be judged precisely. The lowering of leptin’s availability in insufficient sleep is associated with increased appetite for sweet, salty and carbohydrates (Spiegel et al., 2004). Other researches demonstrate dose-dependent reduction of food intake when increased administration of leptin in the blood is present. (Woods and Seeley, 2000). Or in other words said, sleep disturbances lower leptin bioavailability which is associated with increased appetite and food intake.
The things, of course, are not so simple. In two other researches (Bosy-Westphall et al, 2008; Nedelcheva et al., 2009) such a link between leptin and sleep disorders is not observed, and Pejovic et al. (2010) demonstrate increased levels of leptin in people after 24h sleep deprivation in a non-stress medium. The authors conclude that sleep deprivation and the activation of the stress system, but not only the lack of sleep per se, are responsible for increased hunger and appetite respectively. The activation of the stress system lowers leptin’s levels and increase appetite for the so called “comfort foods” (fast carbohydrates) (Dallman et al., 2003).
A significant part of the literature focuses on the relationship between the lack of sleep and the disorders in cognitive function. Sleep deprivation affects the centers in the pre-frontal cortex, responsible for control, targeted behavior and cognitive modulation of impulses and emotions both in adults and children.
In conclusion, sleep problems including reduced sleep time and improper sleeping are linked with increased food intake both in adults and children. So, sleep hygiene is essential for proper metabolism and not only. See the consequences of sleep deprivation:
I show you systematically a modified list of advices of WHO for better sleep and fast falling asleep:
- Consume light dinner and try to finish with any intake of foods or beverages at least two hours before you put your body in a horizontal position.
- Say no to alcohol before going to bed. Although alcohol leads to fast and easy falling asleep, it is a cause of frequent awakenings during the night.
- Granny’s socks. Some people have problems with warming of their feet. Warmer extremities help in falling asleep faster according to a study.
- Dark room. Even the most unnoticeable light, such as that of a digital clock, may prevent you from falling asleep. If you cannot remove the offending light, consider the idea of using sleep mask at night.
- Proper temperature. A room that is too hot or too cold may be the cause of poor sleep. The optimum temperature for sleep is between 15-19 degrees.
- Switch off everything. Pull the curtains, turn off all devices – mobiles, TV, laptop, one hour before bedtime. The light is a signal to the brain to be awake and alert, so begin to send the opposite signal shortly before going to bed.
- Reduce caffeine. Excessive use of caffeine, especially in the afternoon may be a reason to wake at night.
- Exercise. According to a study performed in America in 2013, people who exercise regularly have a much better sleep. It doesn’t require much – add just several minutes of training during the day and you’ll improve your sleep.
- Bed is only for sleep and some authors add love. Use it on purpose.
- Silence in the room. If you have problems with falling asleep because of unpleasant or irritating sounds, snoring partner or the ticking of the clock, use earplugs.
- Mattress. Sometimes the culprit for turning over in the bed and the inability to fall asleep is below you. The uncomfortable mattress may be the reason for your insomnia. No matter if it has lost its softness or if it is short, you shouldn’t put it off until other time. Experts recommend replacing the mattress every 5-10 years.
- Nap. A short nap during the day (no more than 30 minutes) won’t interfere with the night sleep. On the contrary, it will even improve your memory, alertness and work.
- Stay routine. When you have sleep problems, it is a good idea to follow the same routine of waking even at weekends. If you remain in bed in the morning or go to sleep too late, you will only impair your natural body clock.
- Meditation or prayer. Help to relax, which make you fall asleep faster. Try to imagine that you are on secluded and peaceful place.
- Pleasant smells. A study in the US in 2005 show that pleasant scents help in falling asleep faster.
- Warm bath. Taking a warm bath before sleep help us falling asleep faster but also more deeply. This is because we rise our body temperature and the moment we go out of the bathroom, it starts to drop, imitating the natural process before the body goes to sleep.
- Sunlight. It is useful to feel the sun beams for at least 15 minutes early in the morning. It helps in regulating the biological clock of the organism.
- New pillow. Sometimes finding the right pillow, as well as the mattress, may solve the sleep problems. Choose your pillow according the most common sleep position. For the stomach sleepers a soft pillow is recommended, for side sleepers – hard, and for back sleepers – medium hard.
- ?kerstedt T (2003) Shift work and disturbed sleep/wakefulness. Occupational Medicine 53(2): 89–94. Abstract
- Allan JL, Johnston M, Campbell N (2011) Missed by an inch or a mile? Predicting the size of intention–behaviour gap from measures of executive control. Psychology & Health 26(6): 635–650. CrossRefMedlineOrder article via InfotrieveGoogle Scholar
- Anderson C, Platten CR (2011) Sleep deprivation lowers inhibition and enhances impulsivity to negative stimuli. Behavioural Brain Research 217(2): 463–466. CrossRefMedlineOrder article via InfotrieveWeb of ScienceGoogle Scholar
- Antunes LC, Levandovski R, Dantas G, et al. (2010) Obesity and shift work: Chronobiological aspects. Nutrition Research Reviews 23(01): 155–168. CrossRefMedlineOrder article via InfotrieveWeb of ScienceGoogle Scholar
- Baicy K, London ED, Monterosso J, et al. (2007) Leptin replacement alters brain response to food cues in genetically leptin-deficient adults. Proceedings of the National Academy of Sciences of the United States of America 104(46): 18276–18279. Abstract/FREE Full Text
- Batterink L, Yokum S, Stice E (2010) Body mass correlates inversely with inhibitory control in response to food among adolescent girls: An fMRI study. NeuroImage 52(4): 1696–1703. CrossRefMedlineOrder article via InfotrieveWeb of ScienceGoogle Scholar
- Beaver JD, Lawrence AD, van Ditzhuijzen J, et al. (2006) Individual differences in reward drive predict neural responses to images of food. Journal of Neuroscience 26: 5160–5166. Abstract/FREE Full Text
- Beebe DW, Fallone G, Godiwala N, et al. (2008) Feasibility and behavioral effects of an at-home multi-night sleep restriction protocol for adolescents. Journal of Child Psychology and Psychiatry 49(9): 915–923. CrossRefMedlineOrder article via InfotrieveWeb of ScienceGoogle Scholar
- Benedict C, Brooks SJ, O’Daly OG, et al. (2012) Acute sleep deprivation enhances the brain’s response to hedonic food stimuli: An fMRI study. The Journal of Clinical Endocrinology & Metabolism 97(3): E443–E447. CrossRefGoogle Scholar
- Berger RH, Miller AL, Seifer R, et al. (2012) Acute sleep restriction effects on emotion responses in 30- to 36-month-old children. Journal of Sleep Research 21(3): 235–246. CrossRefMedlineOrder article via InfotrieveGoogle Scholar
- Brondel L, Romer MA, Nougues PM, et al. (2010) Acute partial sleep deprivation increases food intake in healthy men. The American Journal of Clinical Nutrition 91(6): 1550–1559. Abstract/FREE Full Text
- Burt J, Dube L, Thibault L, et al. (2014) Sleep and eating in childhood: A potential behavioral mechanism underlying the relationship between poor sleep and obesity. Sleep Medicine Reviews 15(1): 71–75. CrossRefGoogle Scholar