Does High Blood Sugar Make You Tired?

Those living with type 1 or type 2 diabetes are generally aware of the symptoms that go along with high blood sugar. For people with a recent diagnosis of the condition or those with normal or prediabetic levels, however, those symptoms may not be as apparent. It can be difficult to differentiate between the symptoms of high blood sugar and other ailments because some can be nonspecific in nature. One of these nonspecific symptoms of high blood sugar that people with diabetes often experience is fatigue.

A man showing a tired expression while working from home

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High Blood Sugar Causes Fatigue

Fatigue is one of the most common symptoms of high blood sugar. In people with diabetes, it is referred to as diabetes fatigue. Many people with the condition feel tired all the time regardless of how well they sleep, how healthily they eat, or how much they exercise on a regular basis. Research has shown that up to 61% of people who are recently diagnosed with the condition experience fatigue. However, fatigue doesn’t just occur in those with diabetes. It can also happen in people with normal or prediabetic blood sugar levels if they experience a sudden spike in their blood sugar.

When the body experiences a spike in blood sugar levels, it goes into overdrive trying to create enough insulin to balance it out. If there isn’t enough insulin or the body isn’t responding to the insulin as it should, your body will start to pull from fat to create the energy it needs. When this happens, energy is used from the splitting of a molecule known as adenosine triphosphate, or ATP. When ATP expels one of its three phosphates for energy, it turns into another molecule known as adenosine diphosphate, or ADP. If there are no energy sources to pull from, the ATP cannot regain the phosphate it gave away, leading to fatigue.

When to See a Doctor

It’s normal to feel fatigued sometimes, but if fatigue lasts longer than two weeks, it may be time to see a doctor. For those who also experience symptoms of blood sugar spikes such as increased thirst, frequent urination, nausea, listlessness, and dizziness, fatigue could be a sign that they have developed or are at risk of developing diabetes. For those who already have the condition, regular appointments to monitor blood glucose and manage diabetes should be done since these symptoms are signs that their current treatment plan is no longer effective.

Management of diabetes fatigue is vital for those with both type 1 and type 2 diabetes. It can be difficult to manage the condition, especially at first, but not impossible. The best way to manage symptoms or complications of the disease is to book an appointment with an endocrinologist, who is specialized in diabetes care. They can help address fatigue and other symptoms by encouraging lifestyle changes such as a healthy diet, more exercise, stress management techniques, and better sleep hygiene.

How to Identify Blood Sugar Spikes

Fatigue is associated with a myriad of other conditions, as well as just day-to-day life and other stressors, so it alone cannot tell you whether you are experiencing a blood sugar spike. People with diabetes are encouraged to keep tabs on their blood sugar levels to detect any sudden changes. This is one of the ways they can identify when blood sugar spikes happen.

The most common cause of high blood sugar (hyperglycemia) is improper insulin production. Insulin is the hormone that is tasked with regulating blood sugar levels, and if it is not being produced at high enough levels or at all, it can lead to high blood sugar levels.

There are few reasons why insulin levels in the body are inadequate, including:

  • Eating too much
  • Not exercising
  • Being chronically stressed
  • Not receiving enough insulin from treatment
  • Having a malfunctioning diabetes pump
  • Having insulin that is ineffective at managing blood sugar levels

Other risk factors that should be taken into consideration include weight, age, history of smoking, cholesterol levels, and blood pressure levels. These can all contribute to diabetes.

For a person without diabetes, insulin levels are unlikely to be considered at all. This is why it can be helpful to keep a food log and note levels of fatigue or other symptoms following every meal. If fatigue generally sets in after eating, it could be a sign that it’s attributed to blood sugar levels. If this does happen, it may indicate that a person should follow up with their doctor and have their blood sugar levels checked.

How to Prevent Blood Sugar Spikes

Blood sugar spikes that cause fatigue can be avoided using certain strategies, including:

  • Eating a balanced diet: By balancing macronutrients such as carbohydrates, fat, and protein, a blood sugar spike can be avoided. Research has shown that the quality of the macronutrients, as well as the amount, plays a vital role in how well the body breaks down the food and how well insulin responds to the food. The best foods to choose are those that are digested slowly and include quinoa, legumes, nuts, fresh fruit, and dairy products. By eating these types of foods, blood sugar levels will rise slower and in a more stable manner.
  • Getting regular exercise: Exercise has been shown to help keep blood sugar levels in check if done regularly. The type of exercise doesn’t matter as much, and both high-intensity and moderate-intensity exercises provided the same results. Endocrinologists generally recommend people exercise after eating.
  • Trading out simple carbs for complex carbs: Eating refined carbs such as white bread, table sugar, and breakfast cereals can all lead to spikes in blood sugar because they are quickly digested. Complex carbs, on the other hand, are not. By choosing complex over refined carbs, you can avoid blood sugar spikes.
  • Taking your vitamins and minerals: Ensuring you’re getting all the nutrients your body needs could also help to control blood sugar levels, especially when it comes to magnesium and chromium. Studies have shown that combining magnesium with chromium could improve insulin resistance and thus help lessen spikes in blood sugar levels.
  • Relaxing: Stress can play a huge role in blood sugar levels. To avoid spikes in blood sugar caused by elevated stress levels, you can practice stress management techniques such as meditation, yoga, or journaling.

Fiber is critical when it comes to crafting a diet that doesn’t cause huge swings in blood sugar. Knowing what type of fiber is good and how much of it to consume is vital.

A Word From Verywell 

High blood sugar can have dangerous repercussions if left untreated. Those with diabetes know the consequences of high blood sugar all too well, but for those who do not, it can be difficult to pin down your risk of developing the condition or ailments that go along with it such as fatigue. The most important thing to do if you believe your fatigue is caused by high blood sugar is to book an appointment with your doctor. They will check your levels, and when that is done, you will be on your way to addressing the issue and getting back to being as healthy as possible.

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  1. Goedendorp MM, Tack CJ, Steggink E, Bloot L, Bazelmans E, Knoop H. Chronic fatigue in type 1 diabetes: highly prevalent but not explained by hyperglycemia or glucose variability. Diabetes Care. 2014;37(1):73-80. doi:10.2337/dc13-0515

  2. Kalra S, Sahay R. Diabetes Fatigue Syndrome. Diabetes Ther. 2018 Aug;9(4):1421-1429. doi:10.1007/s13300-018-0453-x

  3. American Diabetes Association. Hyperglycemia (High Blood Glucose).

  4. Bellou V, Belbasis L, Tzoulaki I, Evangelou E. Risk factors for type 2 diabetes mellitus: An exposure-wide umbrella review of meta-analyses. PLoS One. 2018 Mar 20;13(3):e0194127. doi:10.1371/journal.pone.0194127

  5. Shafaeizadeh S, Muhardi L, Henry CJ, van de Heijning BJM, van der Beek EM. Macronutrient Composition and Food Form Affect Glucose and Insulin Responses in Humans. Nutrients. 2018 Feb 8;10(2):188. doi:10.3390/nu10020188

  6. Parker L, Shaw CS, Banting L, Levinger I, Hill KM, McAinch AJ, Stepto NK. Acute Low-Volume High-Intensity Interval Exercise and Continuous Moderate-Intensity Exercise Elicit a Similar Improvement in 24-h Glycemic Control in Overweight and Obese Adults. Front Physiol. 2017 Jan 9;7:661. doi:10.3389/fphys.2016.00661

  7. Dou M, Ma Y, Ma AG, Han L, Song MM, Wang YG, Yao MX, Sun XF, Li Y, Gao S, Zhang Y. Combined chromium and magnesium decreases insulin resistance more effectively than either alone. Asia Pac J Clin Nutr. 2016 Dec;25(4):747-753. doi:10.6133/apjcn.092015.48

  8. Sancini A, Ricci S, Tomei F, Sacco C, Pacchiarotti A, Nardone N, Ricci P, Suppi A, De Cesare DP, Anzelmo V, Giubilati R, Pimpinella B, Rosati MV, Tomei G. Work related stress and blood glucose levels. Ann Ig. 2017 Mar-Apr;29(2):123-133. doi:10.7416/ai.2017.2139