The links between diet and sleep, and sleep and diet
When people visit a nutritional therapist, they expect the conversation to just focus on what they are eating, what they are not eating, and what they should be eating! So when the discussion turns to sleeping patterns and quality of sleep this can come as a surprise.
Actually sleep, and getting good sleep, is more connected to your diet and than you might think…
Food and your sleep
So, of course caffeine at bed time is not going to promote sleep! So if you are drinking coffee, green tea, energy drinks etc before bedtime, you may want to ditch this habit!
But there are other foods and aspects of your overall diet that can also influence how easily you drop off to sleep, and the quality of your sleep. For example, while eating a high carbohydrate meal is associated with increasing sleepiness (think of that post-pasta slump), it has also been shown to decrease sleep quality, increasing the number of times you wake up and decreasing your deep sleep (1).
Blood-sugar regulation may have a large role to play in your sleep quality.
You need sugars circulating in your blood, as these provide your cells with energy, however both high and low levels can be harmful. Therefore your body has clever mechanisms to make sure your blood sugar levels stay at the sweet spot (pun intended!).
So, in the high carb meal at night example, if you eat carbohydrates, particularly refined ones (think things like white pasta, white bread, cake), your blood sugar level will rise quickly. In order to cope with this your pancreas will pump out lots of Insulin. Insulin tells your body cells to take up that sugar from your blood, however, because your sugar levels went up quickly your body over-reacts by making too much insulin. The result is that your cells take up too much sugar, making the levels in your blood dip to a low level. When blood sugar drops below the sweet spot, your body reacts by making the stress hormones cortisol and adrenaline, which at night time will reduce the quality of your sleep and may even wake you up completely.
Therefore, a blood sugar balancing diet low in refined carbs and high in fibre may be a good place to start if you want to improve your sleep quality.
Sleep and your food
What you eat and drink most definitely will impact on your sleep, but what about the other way around? The amount of sleep you get and the quality of that sleep has been shown in many studies to influence what you eat.
For example, reducing sleep duration has been shown to increase energy intake (3), snacking (4) and intake of calories from fats (5), and unsurprisingly therefore poor sleep has been cited as a possibly contributing factor to obesity (6, 7).
Why reduced sleep has these effects is being extensively studied, and may in part be due to levels of hormones involved in appetite regulation becoming disrupted (levels of the appetite promoting hormone Ghrelin increase, and appetite reducing hormone Leptin decrease with sleep deprivation (8) ) as well as fatigue resulting in lower physical activity (9).
So to wrap up, there are clear links between what you eat and your sleep, and your sleep and what you eat! Keeping both of these relationships in mind can help you make changes to your diet and eating patterns to improve your sleep, and to make changes to your sleeping patterns to give you greater control over what you eat. I will look at strategies for both of these in upcoming posts :)
Fabia x
St-Onge, M. P., Mikic, A., & Pietrolungo, C. E. (2016). Effects of Diet on Sleep Quality. Advances in nutrition (Bethesda, Md.), 7(5), 938–949. https://doi.org/10.3945/an.116.012336
Gangwisch JE, Hale L, St-Onge MP, Choi L, LeBlanc ES, Malaspina D, Opler MG, Shadyab AH, Shikany JM, Snetselaar L, Zaslavsky O, Lane D. High glycemic index and glycemic load diets as risk factors for insomnia: analyses from the Women's Health Initiative. Am J Clin Nutr. 2020 Feb 1;111(2):429-439. doi: 10.1093/ajcn/nqz275. PMID: 31828298; PMCID: PMC6997082.
St-Onge MP, Roberts AL, Chen J, Kelleman M, O'Keeffe M, RoyChoudhury A, Jones PJ. Short sleep duration increases energy intakes but does not change energy expenditure in normal-weight individuals. Am J Clin Nutr. 2011 Aug;94(2):410-6. doi: 10.3945/ajcn.111.013904. Epub 2011 Jun 29. PMID: 21715510; PMCID: PMC3142720.
Nedeltcheva AV, Kilkus JM, Imperial J, Kasza K, Schoeller DA, Penev PD. Sleep curtailment is accompanied by increased intake of calories from snacks. Am J Clin Nutr. 2009 Jan;89(1):126-33. doi: 10.3945/ajcn.2008.26574. Epub 2008 Dec 3. PMID: 19056602; PMCID: PMC2615460.
Weiss A, Xu F, Storfer-Isser A, Thomas A, Ievers-Landis CE, Redline S. The association of sleep duration with adolescents' fat and carbohydrate consumption. Sleep. 2010 Sep;33(9):1201-9. doi: 10.1093/sleep/33.9.1201. PMID: 20857867; PMCID: PMC2938861.
Patel SR. Reduced sleep as an obesity risk factor. Obes Rev. 2009 Nov;10 Suppl 2:61-8. doi: 10.1111/j.1467-789X.2009.00664.x. PMID: 19849803.
Beccuti, G., & Pannain, S. (2011). Sleep and obesity. Current opinion in clinical nutrition and metabolic care, 14(4), 402–412. https://doi.org/10.1097/MCO.0b013e3283479109
Morselli L, Leproult R, Balbo M, Spiegel K. Role of sleep duration in the regulation of glucose metabolism and appetite. Best Pract Res Clin Endocrinol Metab. 2010 Oct;24(5):687-702. doi: 10.1016/j.beem.2010.07.005. PMID: 21112019; PMCID: PMC3018785.
Schmid SM, Hallschmid M, Jauch-Chara K, Wilms B, Benedict C, Lehnert H, Born J, Schultes B. Short-term sleep loss decreases physical activity under free-living conditions but does not increase food intake under time-deprived laboratory conditions in healthy men. Am J Clin Nutr. 2009 Dec;90(6):1476-82. doi: 10.3945/ajcn.2009.27984. Epub 2009 Oct 21. PMID: 19846546.
