Chrononutrition and Diabetes: Can the time you eat impact your blood sugar levels?

By: Terence Yeung

Relationship between Circadian Rhythms and Meal Timing

For diabetics, diet is incredibly impactful on their health. However, emerging evidence indicates that the timing of meals may be as crucial as what you consume (BaHammam & Pirzada, 2023; Crispim & Mota, 2019). As it turns out, the circadian rhythm and eating are highly related to each other. The internal circadian clock is responsible for maintaining a 24-hour cycle that regulates various physiological processes within the human body, including sleep, metabolism, and body temperature (BaHammam & Pirzada, 2023). Circadian rhythms and eating have a complex relationship which involves both endogenous factors, such as the circadian clock, and external factors like hormone production. Both circadian rhythms and feeding behaviour can influence each other and regulate many aspects of the body (Crispim & Mota, 2019). Chrononutrition is a novel field that focuses on how meal timing can impact health and metabolism.

Diabetes and Meal Timing

            The evidence suggests that later meal timings can negatively impact health outcomes. For example, consuming meals when melatonin levels are elevated can contribute to a greater risk of diabetes (melatonin is a hormone that is secreted more at nighttime when there is less light)1. Furthermore, for those who already have diabetes, patients who eat later at night are more likely to become obese and have elevated blood sugar levels (Sato et al., 2011). One of the reasons for this is that glucose tolerance decreases around midnight. This hyperglycemia can have serious consequences on their health, ranging from more mild symptoms like repeated urination to more serious long-term complications like heart disease (Balaji et al., 2019).

There are other behavioural or lifestyle aspects which can influence a person’s risk of diabetes as well. One example of a group that is susceptible to developing diabetes mellitus is shift workers (Gan et al., 2015). This is because shift work involves irregular hours of work compared to a typical daytime work schedule. There are multiple potential explanations for the relationship between shift work and diabetes. One of which is that because of the irregular work schedule, the sleep and mealtime schedule of shift workers is also compromised, leading to a desynchrony of circadian rhythms. It is known that circadian disruption can contribute to the development of diabetes. Furthermore, shift workers have altered nutritional intake compared to someone on a typical working schedule, which includes an increased number of eating events, lower intake of vegetables, and increased consumption of food with a high glycemic index (Crispim & Mota, 2019).

It is important to note that meal timing consistency is also essential in determining health. Irregular meal timing is a predictor of chronic diseases such as diabetes, cardiovascular diseases, sleep disorders, and compromised mental health2. Furthermore, skipping breakfast is associated with a significantly greater risk of type II diabetes (Crispim & Mota, 2019). Breakfast is considered the most important meal of the day because it provides sustenance and energy, allowing for us to prepare for the stress and activities which take place over the course of the day (Spence, 2017). This association between skipping breakfast and increased risk of diabetes is particularly concerning given that one study revealed that nearly half of university students sometimes, rarely, or never eat breakfast (Pengpid & Peltzer, 2020).

Potential Interventions

Based on the information already mentioned, eating meals earlier in the day can help to increase glucose tolerance and also boost other aspects of health. Eating an early dinner can help enhance digestion, boost metabolism, improve sleep, and reduce blood pressure (Kinsey & Ormsbee, 2015). Another intervention relating to meal timing which is currently a hot research topic is time-restricted feeding. This means restricting eating duration (total length of time between the first and last caloric intake of the day). A common type of time-restricted feeding is 16:8, meaning fasting for 16 hours and then having an 8-hour eating window. The research so far suggests that along with a multitude of beneficial impacts, fasting can reduce fasting blood glucose (Crispim & Mota, 2019). However, it is important to note that this would have a large impact on your life, and the research is not completely conclusive at this point in time. Still, if you are already considering either eating earlier or time-restricted eating, you might want to do some more research and consider implementing them into your daily life.

Final Words

With all this said, it should be recognized that eating late every now and then will probably not have much of an impact on your health. However, it is still good to understand that building healthy habits and trying to eat at consistent times can have positive impacts on your health.  By recognizing the importance of meal timing, we can empower ourselves to make choices that support our overall health and well-being.

References

BaHammam, A. S., & Pirzada, A. (2023). Timing Matters: The Interplay between Early Mealtime, Circadian Rhythms, Gene Expression, Circadian Hormones, and Metabolism—A Narrative Review. Clocks & Sleep, 5(3), 507–535. https://doi.org/10.3390/clockssleep5030034

Crispim, C.A., & Mota, M.C. (2019). New perspectives on chrononutrition. Biological Rhythm Research, 50(1), 63–77. https://doi.org/10.1080/09291016.2018.1491202

Balaji, R., Duraisamy, R., & Kumar, S. (2019). Complications of diabetes mellitus: A review. Drug Invention Today. Retrieved March 23, 2024, from https://openurl.ebsco.com/EPDB%3Agcd%3A14%3A3175614/detailv2?sid=ebsco%3Aplink%3Ascholar&id=ebsco%3Agcd%3A134240957&crl=f

Gan, Y., Yang, C., Tong, X., Sun, H., Cong, Y., Yin, X., Li, L., Cao, S., Dong, X., Gong, Y., Shi, O., Deng, J., Bi, H., & Lu, Z. (2015). Shift work and diabetes mellitus: A meta-analysis of observational studies. Occupational and Environmental Medicine, 72(1), 72–78. https://doi.org/10.1136/oemed-2014-102150

Kinsey, A., & Ormsbee, M. (2015). The Health Impact of Nighttime Eating: Old and New Perspectives. Nutrients, 7(4), 2648–2662. https://doi.org/10.3390/nu7042648

Pengpid, S., & Peltzer, K. (2020). Skipping Breakfast and Its Association with Health Risk Behaviour and Mental Health Among University Students in 28 Countries. Diabetes, Metabolic Syndrome and Obesity: Targets and Therapy, 13, 2889–2897. https://doi.org/10.2147/DMSO.S241670

Sato, M., Nakamura, K., Ogata, H., Miyashita, A., Nagasaka, S., Omi, N., Yamaguchi, S., Hibi, M., Umeda, T., Nakaji, S., & Tokuyama, K. (2011). Acute effect of late evening meal on diurnal variation of blood glucose and energy metabolism. Obesity Research & Clinical Practice, 5(3), e220–e228. https://doi.org/10.1016/j.orcp.2011.02.001

Spence, C. (2017). Breakfast: The most important meal of the day? International Journal of Gastronomy and Food Science, 8, 1–6. https://doi.org/10.1016/j.ijgfs.2017.01.003