The Essential Relationship Between Sleep and Inflammation

Excess inflammation is associated with many medical diseases such as cardiovascular disease, autoimmune diseases, metabolic disorders, and neurodegenerative diseases such as Alzheimer’s disease. Research also confirms an association between inflammation and most mental health conditions such as depression, bipolar disorder, and schizophrenia.

There is accumulating evidence demonstrating a relationship between inflammation and sleep problems such as insomnia. For example, higher levels of C-reactive protein (CRP), a blood marker of inflammation, was found in young adults with insomnia [1]. In a meta-analysis (where the results of several studies are collectively examined) also confirmed higher inflammation associated with both sleep disturbances and long sleep duration. [2]

Poor sleep can be a driver of this inflammation as studies show that if you restrict people’s sleep, inflammatory markers increase [2,3]. However, it is likely that the relationship between inflammation and insomnia is bi-directional. That is, poor sleep increases inflammation, and inflammation negatively affects sleep quality. This finding is important as research confirms that both sleep and inflammation are independently associated with an increased risk of medical diseases such as cardiovascular disease, diabetes, autoimmune diseases, pain conditions, and neurodegenerative diseases.  Poor sleep and inflammation also increase the risk of suffering from depression and contributes to treatment-resistant depression.

This research suggests that it is important to consider treatments that improve sleep and reduce inflammation. For example, improving sleep hygiene and cognitive behaviour therapy for insomnia should be implemented in people with sleep problems. However, it may also be important to introduce strategies to reduce inflammation. This includes:

• Eating anti-inflammatory foods (e.g., fruits, vegetables, spices, seafood)
• Reducing the intake of pro-inflammatory foods (e.g., take away and fast foods, cakes, pastries, high-sugar foods, refined white products)
• Improving digestive health
• Supplementing with anti-inflammatory nutrients, herbs, and supplements (e.g., omega-3 fatty acids, magnesium, curcumin, saffron, ginger)
• Reducing stress
• Engaging in moderate exercise
• Losing weight
• Identifying and treating sleep apnoea and other inflammatory medical conditions
• Supplementing with sleep-enhancing, anti-inflammatory ingredients. For example, magnesium can help improve sleep and is also a powerful anti-inflammatory. [4] There is also research supporting the sleep-promoting benefits of Tart Cherry Juice, which also has anti-inflammatory effects. [5]. Glycine is an amino acid that can also improve sleep and is an effective anti-inflammatory. [6,7]

If you experience sleep problems, it is recommended you use a double-pronged approach by targeting your sleep directly AND implementing strategies to reduce inflammation.

References

1. Slavish DC, et al. Insomnia symptoms are associated with elevated C-reactive protein in young adults. Psychol Health. 2018 Oct 25:1-20. link to article
2. Irwin MR, et al. Sleep Disturbance, Sleep Duration, and Inflammation: A Systematic Review and Meta-Analysis of Cohort Studies and Experimental Sleep Deprivation. Biol Psychiatry. 2016 Jul 1;80(1):40-52. link to article
3. Kincheski GC, et al. Chronic sleep restriction promotes brain inflammation and synapse loss, and potentiates memory impairment induced by amyloid-β oligomers in mice. Brain Behav Immun. 2017 Aug;64:140-151. link to article
4. Abbasi B, et al. The effect of magnesium supplementation on primary insomnia in elderly: A double-blind placebo-controlled clinical trial. J Res Med Sci. 2012 Dec;17(12):1161-9. link to article
5. Losso JN, et al. Pilot Study of the Tart Cherry Juice for the Treatment of Insomnia and Investigation of Mechanisms. Am J Ther. 2018 Mar/Apr;25(2):e194-e201. link to article
6. Bannai M & Kawai N. New therapeutic strategy for amino acid medicine: glycine improves the quality of sleep. J Pharmacol Sci. 2012;118(2):145-8. link to article
7. Zhong Z, et al. L-Glycine: a novel antiinflammatory, immunomodulatory, and cytoprotective agent. Curr Opin Clin Nutr Metab Care. 2003 Mar;6(2):229-40. link to article