Sleep and Blood Glucose Levels

Updated December 4, 2020

Written by

Medically Reviewed by

Fact Checked

Every night—regardless of whether you sleep—your blood sugar levels increase as a part of the natural human circadian rhythm cycle. Blood sugar levels also increase during sleep. Blood sugar fluctuations that occur overnight and during sleep are normal and not a cause for concern for most healthy people.

Sleep also plays an important role in maintaining healthy blood sugar levels. Over the past few decades, the overall average number of hours slept each night has apparently decreased. This decrease in sleep may have contributed to the increase in obesity and diabetes that occurred over the same stretch of time. Obesity and diabetes are affected by blood sugar levels, while one’s blood sugar also impacts obesity and diabetes. As a result, blood sugar could be one of the factors involved in weight loss and sleep.

Sleep and physical health are closely connected, so it’s not surprising that sleep affects blood sugar levels. However, the relationship between sleep and blood sugar is complex. There isn’t a simple formula that demonstrates a relationship between the amount of sleep and a corresponding increase or decrease in blood sugar.

Can Sleep Raise or Lower Glucose Levels?

Although it sounds contradictory, sleep can both raise and lower glucose levels. Our bodies experience a cycle of changes every day—called a circadian rhythm—which naturally raises blood sugar levels at night and when a person sleeps. These natural blood sugar elevations are not a cause for concern.

Restorative sleep might also lower unhealthy blood sugar levels by promoting healthy systems. Decreased sleep is a risk factor for increased blood sugar levels. Even partial sleep deprivation over one night increases insulin resistance, which can in turn increase blood sugar levels. As a result, a lack of sleep has been associated with diabetes, a blood sugar disorder.

More research is needed to better understand the connection between sleep and blood sugar. So far, the following factors have been found to influence the relationship between sleep and blood sugar levels:

The amount of time a person sleeps
The stages of sleep a person experiences
The time of day a person sleeps
A person’s age
A person’s eating habits (which overlaps with nutrition and sleep)

Why Does Sleep Affect Blood Sugar?

Researchers are beginning to uncover why sleep affects blood sugar and which underlying mechanisms are at play. So far, they’ve learned that the following physiological factors play a role in the relationship between sleep and blood sugar:

Cortisol is increased by sleep deprivation and increases glucose
Insulin sensitivity is reduced by sleep deprivation and impacts glucose
The time of day a person sleeps impacts insulin and cortisol levels, both of which affect glucose
Increases in growth hormone accompany glucose increases during sleep
Oxidative stress and inflammation are increased by sleep deprivation and impact glucose
C-reactive protein is increased by sleep deprivation and can impact glucose
Inflammatory markers IL-6 and TNF-𝝰 are increased by sleep deprivation and can cause insulin resistance, which impacts glucose

How Does Blood Glucose Affect Sleep?

Just as sleep affects blood sugar levels, blood sugar levels may also impact sleep quality. A study of people with type 2 diabetes found that those with higher blood sugar levels experience poorer sleep. Another study found that 62% of people with glucose levels in the pre-diabetes range are likely to have poor sleep, compared to 46% of people with normal glucose levels.

Researchers aren’t certain why increased blood sugar may be associated with poor sleep and more study is necessary to understand the relationship.

Can Low Blood Sugar Cause Sleep Problems?

Low blood sugar, called hypoglycemia, can cause sleep problems. Hypoglycemia can occur in people with or without diabetes. Nocturnal hypoglycemia is a form of hypoglycemia that occurs at night.

According to the National Institute of Diabetes and Digestive and Kidney Diseases, low blood sugar during sleep can cause the following symptoms:

Nightmares
Crying or yelling during sleep
Sweating profusely
Feeling irritable or confused upon waking

Do Sleep Problems Affect Blood Sugar?

Since a lack of sleep and blood sugar levels are related, it makes sense that not sleeping well can raise blood sugar levels. Researchers have suggested the following connections between sugar and lack of sleep or sleep problems:

Sleep disordered breathing is associated with higher glucose levels
Obstructive sleep apnea is associated with impared glucose tolerance
More severe sleep breathing issues are associated with higher blood sugar
Obstructive sleep apnea severity is associated with increased fasting glucose
Poor sleep is associated with a reduced ability to control glucose levels in diabetic patients
Inadequate sleep is associated with type 2 diabetes biomarkers, even in children
Sleep loss is associated with increased glucose levels in hospitalized patients with and without diabetes

Was this article helpful?
Yes No

References
+23 Sources
1. 1. Van Cauter, E., Blackman, J. D., Roland, D., Spire, J. P., Refetoff, S., & Polonsky, K. S. (1991). Modulation of glucose regulation and insulin secretion by circadian rhythmicity and sleep. Journal of Clinical Investigation, 88(3), 934–942. https://pubmed.ncbi.nlm.nih.gov/1885778/
2. 2. Rains, J. L., & Jain, S. K. (2011). Oxidative stress, insulin signaling, and diabetes. Free Radical Biology and Medicine, 50(5), 567–575. https://pubmed.ncbi.nlm.nih.gov/21163346/
3. 3. Knutson, K. L. (2007). Impact of Sleep and Sleep Loss on Glucose Homeostasis and Appetite Regulation. Sleep Medicine Clinics, 2(2), 187–197. https://pubmed.ncbi.nlm.nih.gov/18516218/
4. 4. Spiegel, K., Knutson, K., Leproult, R., Tasali, E., & Cauter, E. V. (2005). Sleep loss: a novel risk factor for insulin resistance and Type 2 diabetes. Journal of Applied Physiology, 99(5), 2008–2019.https://pubmed.ncbi.nlm.nih.gov/16227462/
5. 5. Donga, E., van Dijk, M., van Dijk, J. G., Biermasz, N. R., Lammers, G.-J., van Kralingen, K. W., Corssmit, E. P. M., & Romijn, J. A. (2010). A Single Night of Partial Sleep Deprivation Induces Insulin Resistance in Multiple Metabolic Pathways in Healthy Subjects. The Journal of Clinical Endocrinology & Metabolism, 95(6), 2963–2968. https://pubmed.ncbi.nlm.nih.gov/20371664/
6. 6. Tasali, E., Leproult, R., Ehrmann, D. A., & Van Cauter, E. (2008). Slow-wave sleep and the risk of type 2 diabetes in humans. Proceedings of the National Academy of Sciences, 105(3), 1044–1049.https://pubmed.ncbi.nlm.nih.gov/18172212/
7. 7. Reutrakul, S., Hood, M. M., Crowley, S. J., Morgan, M. K., Teodori, M., Knutson, K. L., & Van Cauter, E. (2013). Chronotype Is Independently Associated With Glycemic Control in Type 2 Diabetes. Diabetes Care, 36(9), 2523–2529. https://pubmed.ncbi.nlm.nih.gov/23637357/
8. 8. Frank, S. A., Roland, D. C., Sturis, J., Byrne, M. M., Refetoff, S., Polonsky, K. S., & Van Cauter, E. (1995). Effects of aging on glucose regulation during wakefulness and sleep. American Journal of Physiology-Endocrinology and Metabolism, 269(6), E1006–E1016. https://pubmed.ncbi.nlm.nih.gov/8572190/
9. 9. Spiegel, K., Leproult, R., & Van Cauter, E. (1999). Impact of sleep debt on metabolic and endocrine function. The Lancet, 354(9188), 1435–1439. https://pubmed.ncbi.nlm.nih.gov/10543671/
10. 10. Meier-Ewert, H. K., Ridker, P. M., Rifai, N., Regan, M. M., Price, N. J., Dinges, D. F., & Mullington, J. M. (2004). Effect of sleep loss on C-Reactive protein, an inflammatory marker of cardiovascular risk. Journal of the American College of Cardiology, 43(4), 678–683.https://pubmed.ncbi.nlm.nih.gov/14975482/
11. 11. Vgontzas, A. N., Papanicolaou, D. A., Bixler, E. O., Lotsikas, A., Zachman, K., Kales, A., Prolo, P., Wong, M.-L., Licinio, J., Gold, P. W., Hermida, R. C., Mastorakos, G., & Chrousos, G. P. (1999). Circadian Interleukin-6 Secretion and Quantity and Depth of Sleep. The Journal of Clinical Endocrinology & Metabolism, 84(8), 2603–2607. https://pubmed.ncbi.nlm.nih.gov/10443646/
12. 12. Vgontzas, A. N., Zoumakis, E., Bixler, E. O., Lin, H.-M., Follett, H., Kales, A., & Chrousos, G. P. (2004). Adverse Effects of Modest Sleep Restriction on Sleepiness, Performance, and Inflammatory Cytokines. The Journal of Clinical Endocrinology & Metabolism, 89(5), 2119–2126.https://pubmed.ncbi.nlm.nih.gov/15126529/
13. 13. Yoda, K., Inaba, M., Hamamoto, K., Yoda, M., Tsuda, A., Mori, K., Imanishi, Y., Emoto, M., & Yamada, S. (2015). Association between Poor Glycemic Control, Impaired Sleep Quality, and Increased Arterial Thickening in Type 2 Diabetic Patients. PLOS ONE, 10(4), e0122521.https://pubmed.ncbi.nlm.nih.gov/25875738/
14. 14. Iyegha, I. D., Chieh, A. Y., Bryant, B. M., & Li, L. (2019). Associations between poor sleep and glucose intolerance in prediabetes. Psychoneuroendocrinology, 110, 104444. https://pubmed.ncbi.nlm.nih.gov/31546116/
15. 15. Johns Hopkins Medicine. (n.d.). Hypoglycemia: Nocturnal. Retrieved November 2020, from https://www.hopkinsmedicine.org/health/conditions-and-diseases/diabetes/hypoglycemia-nocturnal
16. 16. National Institute of Diabetes and Digestive and Kidney Diseases. (2016, August). Low Blood Glucose (Hypoglycemia). https://www.niddk.nih.gov/health-information/diabetes/overview/preventing-problems/low-blood-glucose-hypoglycemia
17. 17. Seicean, S., Kirchner, H. L., Gottlieb, D. J., Punjabi, N. M., Resnick, H., Sanders, M., Budhiraja, R., Singer, M., & Redline, S. (2008). Sleep-Disordered Breathing and Impaired Glucose Metabolism in Normal-Weight and Overweight/Obese Individuals: The Sleep Heart Health Study. Diabetes Care, 31(5), 1001–1006. https://pubmed.ncbi.nlm.nih.gov/18268072/
18. 18. Meslier, N., Gagnadoux, F., Giraud, P., Person, C., Ouksel, H., Urban, T., & Racineux, J.-L. (2003). Impaired glucose-insulin metabolism in males with obstructive sleep apnoea syndrome. European Respiratory Journal, 22(1), 156–160. https://pubmed.ncbi.nlm.nih.gov/12882466/
19. 19. Punjabi, N. M., Shahar, E., Redline, S., Gottlieb, D. J., Givelber, R., & Resnick, H. E. (2004). Sleep-Disordered Breathing, Glucose Intolerance, and Insulin Resistance: The Sleep Heart Health Study. American Journal of Epidemiology, 160(6), 521–530. https://pubmed.ncbi.nlm.nih.gov/15353412/
20. 20. Papanas, N., Steiropoulos, P., Nena, E., Tzouvelekis, A., Maltezos, E., Trakada, G., & Bouros, D. (2009). HbA1c is associated with severity of obstructive sleep apnea hypopnea syndrome in nondiabetic men. Vascular Health and Risk Management, 5, 751. https://pubmed.ncbi.nlm.nih.gov/19774216/
21. 21. Brouwer, A., van Raalte, D. H., Rutters, F., Elders, P. J. M., Snoek, F. J., Beekman, A. T. F., & Bremmer, M. A. (2019). Sleep and HbA1c in Patients With Type 2 Diabetes: Which Sleep Characteristics Matter Most? Diabetes Care, 43(1), 235–243. https://pubmed.ncbi.nlm.nih.gov/31719053/
22. 22. Dutil, C., & Chaput, J.-P. (2017). Inadequate sleep as a contributor to type 2 diabetes in children and adolescents. Nutrition & Diabetes, 7(5), e266. https://pubmed.ncbi.nlm.nih.gov/28481337/
23. 23. DePietro, R. H., Knutson, K. L., Spampinato, L., Anderson, S. L., Meltzer, D. O., Van Cauter, E., & Arora, V. M. (2016). Association Between Inpatient Sleep Loss and Hyperglycemia of Hospitalization. Diabetes Care, 40(2), 188–193. https://care.diabetesjournals.org/content/40/2/188