I came across this report recently of a study which found that stopping men sleeping for a night led to them choosing bigger portions of ‘energy-dense’ food at a buffet . Previous work from the same group at Uppsala University in Sweden found that sleep deprivation caused greater activity in the parts of the brain linked to the desire to eat in response to being shown pictures of food .
It’s become clear over the years, I think, that cutting back on sleep has the potential to drive weight gain through more than one mechanism. Certainly, there is some evidence that depriving ourselves of sleep can make us hungrier. It also, by the way, gives us more opportunity to eat.
Lack of sleep can also cause people to be more fatigued, which may reduce the amount of energy they expend eat day. This might further tip the scales in favour in weight gain.
Sleep deprivation has also been shown in studies to promote ‘insulin resistance’ – a state where insulin is not doing it’s job properly and both insulin levels and blood sugar levels can rise. As insulin is a chief fat storage hormone, this mechanism might also promote weight gain.
Another potential effect of sleep deprivation is to raise levels of the stress hormone cortisol. In excess, this hormone promotes the deposition of fat (particularly around the midriff) and, at the same time, promotes the breakdown of muscle. Even if weight were not to change as a result, clearly this may have a negative impact on body composition.
All-in-all, the evidence suggests that getting adequate amounts of sleep will assist weight control and have other benefits for health. Some people wonder where they will find the time for more sleep. Well, sleeping in is usually not an attractive option in the week when there’s work to do and kids to get to school etc. So, getting into bed earlier is often the only really viable option. This can mean being quite disciplined about one’s engagement with sleep thieves such as TV-watching. This can not only encroach on sleep time, but can also lead to use eating more. I wrote about this here.
1. Hogenkamp PS, et al. Acute sleep deprivation increases portion size and affects food choice in young men. Psychoneuroendocrinology (in press)
2. Benedict C, et al. Acute sleep deprivation enhances the brain’s response to hedonic food stimuli: an fMRI study. J Clin Endocrinol Metab. 2012;97(3):E443-7.