This topic gets banded around quite a lot, yet the mechanisms of how sleep can impact eating behaviours are not often discussed. A new discussion was published in the Journal of Health Psychology, by Lundahl and Nelson, on the factors linking poor sleep with poor diet. Their findings will be summarised below.
Lack of sleep results in:
It has been shown that lack of sleep can impact on the hormone levels naturally produced within the human body. The two main hormones related to appetite are leptin and ghrelin.
Leptin signals satiety (satisfaction/no need for food)
Ghrelin triggers the appetite response
The ration between those two hormones is said to be a significant predictor in hunger after sleep depravation. In particular, it is thought that a decrease in leptin increases the desire for sweet, sticky, and salty foods - comfort foods.
Executive Function/Behavioural Impairment
The executive function is involved in self-regulation, reasoning, and planning.
Lack of sleep has been shown to weaken the executive function, leading to increased impulsivity and the seeking of highly rewarding foods. This has a direct link to the hunt for highly calorific, satisfying, tasty treats! In particular highly fattening foods and snacks. In addition, the consumption of fruits and vegetables plummets.
Sleep depravation can amplify how the brain processes pleasurable stimuli, increasing the sense of reward in energy dense foods.
The sleep process helps the brain to process recent emotional experiences and prepares us to cope with new experiences and emotional onslaughts each day. Depriving the brain of sleep results in this process not functioning, and therefore coping with new emotional struggles becomes more and more challenging.
As emotional eaters are well aware, eating is a 'great' way of altering mood. Albeit temporarily. Therefore, people who lack sleep and want to improve their mood often turn to energy dense foods and drinks in order to feel better. A prime example is a tub of Ben & Jerry's, chocolate, coca cola etc. A form of emotional regulation through the consumption of rewarding foods. Often people can use wine for this purpose too, a buzz from both the alcohol and sugar content (this can have disastrous consequences if not resolved quickly).
The cumulative process
It is quite apparent that the above do not work in solitude. It is likely that they harmoniously work together, contributing to weight gain and enhancing any negative moods. The fear of failure due to not sticking to the latest diet plan, due to gaining weight despite wanting to lose some that week.
Are you struggling to shed those pounds, maybe you need to consider how many hours of sleep you're getting each night. If is estimated that the average adult should get 6-7 hours a night. The body truly needs this to function properly. Directly tacking your sleeping patterns could, in itself, help reduce the risk of chronic illness such as diabetes and cardiovascular disease.
I'm a doctor of psychology, born in Guernsey, educated at a tertiary level in Bristol, Bath, and London. Having worked and trained with some of the leading Health Psychologists in the UK, and having a passion about how Health Psychology can truly benefit many people, I now want to spread the word, as well as offer consultations to people wanting to make changes in their lives.