Late Night with Hypoglycemia

Have you ever found yourself in this situation? It’s late; you’re either studying hard for an exam or working up to the last minute on an important assignment. You’ve quickly burned through the midnight oil, filled with anxiety of the impending deadline, and all of the sudden your blood sugar is plummeting! As if you didn’t have enough to worry about, now you have to take precious time (that you can’t really afford to waste) to correct this pressing issue.

Studying for my medical licensing boards was really the first time I found myself in these situations with enough frequency to finally recognize this problem. After two years in school of specific, contained body systems learning, all of the sudden I was being tested on what appeared to be every bit of science I had learned over the years in both my graduate and undergraduate studies combined. So every night in the days leading up to my exam, I found myself studying with an intensity I had never experienced before, and over a longer duration of time. My blood sugars certainly reflected this change. It seemed that without fail, I would be studying late in to the night with an even blood glucose trend, until I would feel abnormally exhausted or have a splitting headache. I would check my blood sugar, and find that I was low seemingly out of nowhere!

So why did this keep happening?

Diabetics are often in tune with the idea of making adjustments for physical activities and exercise, but how often do we account for all the mental activities an exercises going on between our ears?

Suddenly, the need for the phrase “Brain Food” is better contextualized when we remember our brains are our most energy-demanding organs, using up to one-half of all the free sugar energy available in the body2. Just as we think about fueling our muscles for different types exercise, we need to similarly fuel our minds differently when we need high-powered brain output for longer time periods than usual.

Our abilities to problem-solve, recall, and learn new information are closely related to our blood glucose levels.

Anyone with Diabetes can attest to the cloudy, impaired thinking that comes with high blood sugars, as well as the anxious, jittery feelings that come with low ones.

As it would turn out, the science behind our brain function tells a more concerning story. When there is not an adequate amount of glucose available to the brain, communication between neurons break down and the proper signaling through neurotransmitters are not sent. Without that communication, your total cognitive function falls and you can no longer remember concepts you committed to memory or solve problems you would normally figure out.

Diving further, studies have used Magnetic Resonance Imaging (MRI) to see specifically the areas of the brain where neuronal firing is impacted by hypoglycemia, and three specific deficiencies were found1,3:

  • Autonomic Activation: the part of the nervous system responsible for control of the bodily functions not consciously directed, such as breathing, the heartbeat, and digestive processes
  • Hypothalamic Function: which controls body temperature, hunger, personality, thirst, fatigue and circadian rhythms
  • Cortical Function: The ability to control body movements, feel sensations, as well as responding to reaction time.

So it’s easy to say that we aren’t ourselves when these effects take place, and the effects of our low blood sugars greatly impact our ability to function when just at a moderately low blood glucose level. There’s of course the risk of coma if it ever were to drop to a level too severe.

On the other side, stuffing our faces with too many carbs and becoming hyperglycemic is, of course, not the answer either.

Excess glucose consumption by our brains can lead to their own memory and cognitive deficiencies.

High blood glucose levels can actually lead to brain atrophy, or shrinking, over a long period of time. As for the blood vessels supplying nutrients to the brain? They can become atherosclerotic, or thickened to where blood flow is severely restricted.

So how can we avoid these horrible outcomes, but still stay up late and get our work done?

It starts with thinking of our brains as we do the muscles in our body. We need our blood sugars to maintain a level high enough to not drop into dangerous zones but not so high as to lead to cloudy and impaired thinking.

As with anything specific to diabetes and your body’s reaction, you should speak with your physician before making any drastic changes to your regimen, but what we hope to offer you here is a few helpful tips to consider:

Lower Basals: Pump users should experiment with slightly lower basal rates for long nights of study or work. For me, lowering my basal settings by about 15-20% for the duration of my extended study time past 11 PM has been especially helpful in avoiding nighttime lows when I am working late.

Snack Smart: “Brain Food” is a necessity to staying awake and focused on the tasks ahead. The dangers arise when you indulge on high carb or glucose concentrated foods. If you snack like I do, it’s not so much one meal and nothing in between, but rather a slow sampling of a variety of foods over a period of time. Continually bolusing insulin over and over again will lead to insulin-stacking, where a lot of insulin will seemingly hit your body all at once and cause your blood sugar levels to plummet at a time much later than you anticipated. Try high-protein and natural fatty foods, which will slow release and lessen your need for high bolus amounts at one time.

Remember Caffeine: When you’re staying up late, you’re often looking for energy from a source coming from a cup, can, or otherwise. Remember that caffeine not only affects your ability to stay awake, but also significantly increases your body’s metabolism. Ordinarily, your body’s metabolism is low at night, so be wary of how your body’s normal glucose ranges may be affected by the shift in inner processing brought to you courtesy of all the caffeine you intake in order to stay awake.

Diabetes complicates social activities, exercise, recreation, and just about every aspect of our lives. Working late into the night is just another aspect for which we need to account. But, same as all other things, with a little forethought, we can avoid the nasty complications that come with uncontrolled blood glucoses that may stand in the way of all that we set out to accomplish.

So Think Ahead, Work Hard, and Carry On!


  1. Cryer, Philip E. “Hypoglycemia, Functional Brain Failure, and Brain Death.”Journal of Clinical Investigation117.4 (2007): 868–870. PMC. Web. 14 May 2017.
  2. Edwards, Scott. “Sugar on the Brain”. On the Brain: The Harvard Mahoney Neuroscience Institute Letter. Havard school of Medicine. http://neuro.hms.harvard.edu/harvard-mahoney-neuroscience-institute/brain-newsletter/and-brain-series/sugar-and-brain. 2017

3. Rosenthal, J. Miranda; Amiel, Stephanie A.; Yágüez, Lidia; Bullmore, Edward; Hopkins, David; Evans, Mark; Pernet, Andrew; Reid, Helen; Giampietro, Vincent; Andrew, Chris M.; Suckling, John; Simmons, Andrew; Williams, Stephen C.R.; Diabetes. American Diabetes Association, 2001 Jul; 50(7): 1618-1626. https://doi.org/10.2337/diabetes.50.7.1618

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