top of page
Recent Posts
Featured Posts

The Three S's - Sleep, Stress & Sugar (Part I)

Everyone always asks me, “Mike, what do I need to eat to look, feel and perform better?” And while nutrition is immensely important, a common problem I run into with clients originates with the 3 S's: sleep, stress and sugar. But the thing is, all three of them are inexorably related. They all influenced by and play a role in modulating our gut microbiome and subsequent hormone, neurotransmitter and immune regulation.

I've talked about it before, and will again at length in the future, but the fact of the matter is our gut bacteria affect most things in our lives more than one might realize. When someone says they have a “gut feeling,” they are not inherently wrong; our guts were our first brains. In fact, our enteric bacteria produce neurotransmitters and hormones, that can affect our biological processes and even our behaviors and actions, particularly by way of modulating the hypothalamus-pituitary-adrenal (HPA) axis [1, 2]. Endotoxins released by your microflora are able to induce inflammation and increase intestinal permeability [3], which in turn opens you up to practically every other health condition imaginable [4]; and unfortunately, stress, be it work, family, relationship, or otherwise induced, can play a role in initiating this process [3, 4].

Now this isn't to say that stress is inherently bad, as there are hormetic stressors, e.g. exercise, that can induce positive effects [5]. In the event a lion is trying to eat you, acute, intermittent stress can be a good thing for your survival, but there is a threshold, which when exceeded too frequently, leads us down this path to inflammation and disease.

Sleep represents a time where our bodies can repair itself and gut bacteria can sort of “thin the herd.” The intestinal bacteria produce neurotransmitters and hormones, such as serotonin and melatonin, that help in the relaxation and subsequent sleep induction process [6]. Moreover, melatonin helps in regulating immune homeostasis [7]. However, sleep deprivation, particularly repeated, results in that chronic stress situation, with a negative effect on immune function and overall health [8].

Now, in the normal system, our bodies work on a circadian sleep-wake cycle with melatonin surging at night to help induce sleep and cortisol spiking in the morning, relatively immediately upon awakening [8, 9]. In an acute situation, this is a good thing, as cortisol is part of the inflammatory control process in the body, as illustrated by the closely related cortisone, commonly given as a shot in response to an injury. However, as mentioned before, there is a threshold and chronically elevated cortisol down-regulates immune function and is associated with the development of atherogenesis, cancer and impaired glucose tolerance [10].

Take note of that last one, impaired glucose tolerance. Normally, in the acute stress response, cortisol helps liberate glucose for energy to respond to the immediate threat, i.e. fight or flight [11]. Using the lion analogy again, this makes sense since it allows you to be able to fight it off or sprint away. Moreover, other non-essential processes, such as hunger and digestion, are down-regulated, as immediate survival is more important, which helps explain the loss of appetite associated with stress [11].

But, generally our stresses today are longer term: “how am I going to pay the mortgage this month?”, “how am I going to meet that deadline at work?”, “why is whoever giving me such a hard time?” This chronic stress results in a situation where your blood sugar is elevated so often, that your cells no longer know how to respond and you get glucose intolerance, hyperglycemia and insulin resistance [11, 12]. This is particularly problematic when the stress is paired with sleep deprivation [12].

Now, this is where it comes full circle, as this chronic hyperglycemia is implicated in the development of opportunistic bacterial overgrowth [13]. This alteration to the gut microflora composition can influence food choices, including inducing cravings for sugar [14, 15]. Unfortunately, when you consume more sugar, these deleterious bacteria are able to flourish [16]. And while it likely doesn't need repeating, what else plays a role in increasing cravings for hyper-palatable, caloric-dense foods? Sleep deprivation!! [17]

So as a quick recap, your body likes homeostasis and works in cycles to maintain it. Lose sleep and you increase stress; increase stress and you alter your gut bacteria and immune function; alter your bacteria and immune function and you increase cravings and negatively influence your neurological and metabolic processes, which in turn makes you unable to defend yourself from further infection and disease. Starting to see where this is important?

I am going to cover each one of the S's in further depth in later articles, but if you are impatient and want an awesome resource, be sure to check out Lights Out: Sleep, Sugar & Survival by T.S. Wiley and Bent Formby.

If you are looking for more information on how to beat the stress, check out this awesome article by my good friend Sara Gustafson: 7 Strategies to Beat Stress.


1) Galland, L. (2014). The gut microbiome & the brain. J Med Food. Vol. 17(12):1261-1272.

4) Moloney, R.D.,, Desbonnet, L., Clarke, G., Dinan, T.G. & Cryan, J.F. (2014). The microbiome: Stress, health & disease. Mamm Genome. Vol. 25(1-2):49-74.

5) Bishopric, N.H. (2012). The virtue of just enough stress: A molecular model. Trans Am Clin Climatol Assoc. Vol. 123:175-192.

6) Wang, Y. & Kasper, L.H. (2014). The role of microbiome in central nervous system disorders. Brain Behav Immun. Vol. 38:1-12.

7) Carrillo-Vico, A., Lardone, P.J., Álvarez-Sánchez, N., Rodríguez-Rodríguez, A. & Guerrero, J.M. (2013). Melatonin: Buffering the immune system. Int J Mol Sci. Vol. 14(4):8638-8683.

8) Besedovsky, L., Lange, T. & Born, J. (2012). Sleep & immune function. Pflugers Arch. Vol. 463(1):121-137.

9) Dedovic, K. & Ngiam, J. (2015). The cortisol awakening response & major depression: examining the evidence. Neuropsychiatr Dis Treat. Vol. 11:1181-1189.

10) Malhotra, S., Sawhney, G. & Pandhi, P. (2004). The therapeutic potential of melatonin: A review of the science. MedGenMed. Vol. 6(2):46.

11) Yau, Y.H. & Potenza, M.N. (2013). Stress & eating behaviors. Minerva Endocrinol. Vol. 38(3):255-267.

12) Rao, M.N., Neylan, T.C., Grunfeld, C., Mulligan, K., Schambelan, M. & Schwarz, J.M. (2015). Subchronic sleep restriction causes tissue-specific insulin resistance. J Clin Endocrinol Metab. Vol. 100(4):1664-1671.

13) Ferolla, S.M., Armiliato, G.N., Couto, C.A. & Ferrari, T.C.(2014). The role of intestinal bacteria overgrowth in obesity-related nonalcoholic fatty liver disease. Nutrients. Vol. 6(12):5583-5599.

14) Norris, V., Molina, F. & Gerwitz, A.T. (2013). Hypothesis: Bacteria control host appetites. J Bacteriol. Vol. 195(3):411-416.

15) Alcock, J., Maley, C.C. & Aktipis, C.A. (2014). Is eating behavior manipulated by the gastrointestinal microbiota? Evolutionary pressures & potential mechanisms. Bioessays. Vol. 36(10):940-949.

16) Brown, K., DeCoffe, D., Molcan, E. & Gibson, D.L. (2012). Diet-induced dysbiosis of the intestinal microbiota & the effects on immunity & disease. Nutrients. 4(8):1095-1119.

17) Greer, S.M., Goldstein, A.N. & Walker, M.P. (2013). The impact of sleep deprivation on food desire in the human brain. Nat Commun. Vol. 4:2259:18pp.

** This post may contain affiliate links. If you make a purchase through an affiliate link, Paleo/ Primal Long Island will receive a very small commission, but your cost will not change. Thank you for supporting my blog!

Follow Us
Search By Tags
  • Facebook Basic Square
  • Twitter Basic Square
  • Google+ Basic Square
bottom of page