High Blood Sugar cause Tiredness
Metabolic Health
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High Blood Sugar and Tiredness

Fatigue and tiredness go hand in hand with a diabetes diagnosis. Ask anyone who has been diagnosed with this condition whether they feel energetic and well-rested, and a majority of them would say no! The chronic nature of the condition is not limited to its direct symptoms and signs, they extend way beyond the erratic nature of the highs and lows and move towards sleeplessness, stress, anxiety, and fatigue. It becomes difficult to function normally in daily life when constant sleepiness and lethargy are looming over the head. Even then, the life of a person with diabetes does not stop. They still need to go ahead with their daily routine and chores no matter how pertinent the fatigue is. 

Not only can diabetes cause fatigue but also it is worse on some days than others. These could be because of the lows and highs in sugar levels. The only time one would feel remotely less tired - yes, less tired, not energetic – would be in the duration that the sugars are more or less in the normal range. This would also have to be for a considerable time duration for the symptoms to not set in. Eventually, fatigue slowly becomes a part of regular life as people learn to push through it.  Read more about gestational diabetes counseling.

Does High Blood Sugar Make You Tired?

There would be a unanimous “yes” to the question – “does high blood sugar make you sleepy?” if you ever happen to ask this to a person with diabetes. Without hesitation, they would be able to list out the high blood sugar symptoms, what it does to their bodies, and how difficult it is to sometimes even keep their eyes open when the sugar level is beyond a certain number.  When the sugars are high, the body feels drained and unusually lethargic. Even the daily life tasks seem like a burden and it takes double the amount of energy to be able to complete those. It becomes tough to concentrate as well making the tasks not only longer but also tiresome overall. 

If you have been diagnosed with diabetes or know someone who is living with it, you may realize the overall patterns and trends of sleepiness. Since the condition can take a lot out of you mentally and physically in terms of the efficient management of the signs and symptoms, high blood sugar levels can create havoc in the body.

What Causes High Blood Sugar?

Since we want to understand “does high blood sugar make you sleepy”?, it would first be important to know and identify the causes of high blood sugars. High blood sugar or hyperglycemia can be caused due to several reasons. All of these reasons and factors can also be interconnected at times and can play a role in the dramatic ups and downs of these levels. When there is too much glucose in the body that is unused and not bound by the insulin molecules, a situation of high blood sugar arises. 

Here are a few of the Causes of Hyperglycemia

  1. Inefficient insulin – It is possible that the medication or the injection that you are using is not optimal and may be expired. 
  2. Incorrect dosage – Constant highs can be caused due to the incorrect calculations and doses of insulin as a result of improper carb counting
  3. Physical activity – A sedentary lifestyle without much physical activity can also lead to high blood sugar levels
  4. Stress – Lack of proper stress management techniques can cause the sugar levels to rise
  5. Illness – Diabetes and sugar levels are highly affected by any other illnesses, even regular ones like cold, cough, or even menses.

Why does High Blood Sugar cause Tiredness?

Several reasons can cause tiredness when diagnosed with diabetes. Diabetes high blood sugar levels symptoms can be one of the major reasons that play a role in the extreme lethargy associated, especially in the duration until the highs are treated with a correction dose. 

During the times when the blood sugars are high, the blood becomes ‘sludgy’. This results in the slowing down of the circulation of blood throughout the body creating a lack of oxygen and nutrients being sent to the cells.

High blood sugars are also associated with inflammation. Because of the excess sugar in the body, the blood vessels are known to get inflamed leading to certain cells called – monocytes entering the brain. This causes fatigue. Also read about urine sugar level.

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Additional Causes of Diabetes Fatigue

If you thought diabetes fatigue was caused simply due to high blood sugars and that preventing them would make life easier, you could not be more wrong. There are a vast multitude of other factors that also come into play that may result in fatigue, sleepiness, and tiredness associated with diabetes.

  1. Depression and other mental health issues that may come as a comorbidity with diabetes
  2. Insomnia or poor and disturbed sleep
  3. Hypo or hyperthyroidism
  4. Lower levels of testosterone
  5. Kidney-related issues
  6. Side effects of any medication
  7. Skipping meals or low levels of carbs
  8. Lack of physical activity
  9. Poor nutrition
  10. Lack of social support 
  11. Diabetes fatigue after eating

Identifying Blood Sugar Spikes

At times, the signs of high blood sugar levels may not be very clear and prominent. In fact, at times, the same person can experience different symptoms during high blood sugar levels as well. Diabetes and sweating fatigue is one of the major symptoms one can look out for during high blood sugars. Essentially, because the sugar levels are high, a person might feel breathless and tired which may result in heavy breathing and fatigue. 

Other symptoms of high blood sugars could be:

  • Feeling hungrier than usual
  • Parched throat and need to drink more water
  • Frequent urination
  • Shaking hands and palms
  • Dizziness
  • Sleepiness and fatigue

Managing Diabetes Fatigue

Diabetes high blood sugar levels are common. You may not always be able to avoid them. However, it is important to not let it play a huge role in creating other issues that could disrupt daily life like chronic fatigue. Therefore, managing this tiredness associated with diabetes is necessary.

  1. Lifestyle changes – Healthy lifestyles and habits are key to good health. Make the right kind of necessary alterations to your lifestyle and include a good and timely diet, exercise, proper sleep-wake cycle, etc.
  2. Social support – A huge and underrated area that can play a role to mitigate the factors that cause fatigue would be having a good social support system. 
  3. Mental health – Make your mental health a priority just like physical health. Mental exhaustion can play a role in creating physical fatigue and depletion of energy levels. 
  4. Maintain optimal sugar levels – Also keep the major factor in mind which is the proper management of diabetes and its symptoms. Keep the highs and lows in check and ensure that there are no erratic and dramatic fluctuations.

Preventing Blood Sugar Spikes

Since we now know the answer to “Does high blood sugar make you sleepy”?, it becomes pertinent to control and prevent these spikes. A problem averted is a problem solved. Ensure that you are treating your highs immediately without delay with a correction dose. Here is how you can prevent spikes in the first place:

  1. Count carbs correctly. Make sure to have an accurate estimate of what you are eating and take the insulin dose accordingly
  2. Keep checking blood sugars to ensure that you have them under control at any time of the day
  3. Adjust your basal insulin in case of sick days.
  4. Keep yourself physically active so that the body can burn any extra sugar. Also know about normal sugar level.


Being aware that diabetes can cause severe fatigue can take a huge load off the people diagnosed. At times, the unexplained nature of why this fatigue sets in can cause more confusion and dejection. Knowing that there is a proper and scientific reason for this can make a difference in the mindset of the individuals having to deal with this condition. Recognize the signs and symptoms of fatigue and engage in proper management of the causes.


Can diabetes cause extreme fatigue?

Yes, at times, diabetes can cause extreme fatigue. This could particularly be true when the sugar levels are way too low or high. Both these conditions can cause different symptoms but they most often than not, lead to tiredness and sleepiness. 

Which type of diabetes causes fatigue?

Any type of diabetes, T1D, T2D, gestational diabetes, LADA, etc can cause fatigue. Since the underlying principles of highs and lows remain the same in all types, the consequences also remain constant.

What are some signs of fatigue?

Fatigue could look like – extreme sleepiness, inability to keep the eyes open, heavy breathing or breathlessness, dizziness, lack of concentration, sweating, etc.

When should you worry about fatigue?

Fatigue, while common, can get worrisome if it is persistent and chronic. When you constantly feel depleted of energy, when you feel sleepy all day, when you are unable to get up from the bed, when you are not able to carry out even simple tasks, that is when you should visit the doctor about this fatigue.


This website's content is provided only for educational reasons and is not meant to be a replacement for professional medical advice. Due to individual differences, the reader should contact their physician to decide whether the material is applicable to their case.