What Causes Low Blood Sugar Levels?

It seems as though there is so much emphasis on high blood sugar. 

However, low blood sugar can be just as dangerous. 

Some might even argue that it can be more dangerous than high blood sugar. 

Low blood sugar can become an emergency situation fairly quickly. If left untreated, it can even lead to seizures and coma.

If you’re not diabetic, then low blood sugar may not be a problem at the top of your mind. But it could still happen to you. 

It’s also important to know what to do in this situation should anyone around you experience dangerously low levels of blood sugar. Let’s get into some of the details on this important topic.

What is low blood sugar?

Low blood sugar is what we call hypoglycemia. This happens when your blood sugar drops too low. It’s important to note that if not treated quickly enough, severe low blood sugar can be dangerous. However, most of the time you can treat it on your own.

Since each person is an individual, low blood sugar can affect people differently from others. Symptoms within one person can change too. 

In general, the symptoms of low blood sugar include the following:

  • Sweating
  • Fatigue
  • Dizziness
  • Hunger
  • Tingling lips
  • Shakiness
  • Trembling
  • Heart palpitations
  • Feeling moody, anxious, tearful, or irritable
  • Turning pale

If you leave your low blood sugar untreated, you can get the following symptoms of severe hypoglycaemia:

  • Weakness
  • Blurry vision
  • Confusion
  • Difficulty concentrating
  • Unusual behavior such as clumsiness and slurred speech
  • Fatigue
  • Seizures or fits
  • Collapsing or losing consciousness

If you develop low blood sugar at night, this could wake you up. This is what we call nocturnal hypoglycemia. It could also cause headache, sweating, and fatigue.

What causes low blood sugar levels in diabetics?

One of the causes of low blood sugar is diabetes mellitus, especially if you are taking insulin. Other diabetes medications can also lead to low blood sugar. 

This includes a group of medications called sulfonylureas, like glibenclamide and gliclazide. This also includes glinide medications, such as repaglinide and nateglinide. 

Other causes of low blood sugar in diabetics include the following:

  • Delaying or skipping meals
  • Not eating enough carbs at your last meal (such as bread, cereal, fruit, pasta, and potatoes)
  • Exercise (especially intense exercise)
  • Drinking alcohol

Get Your FREE Diabetes Diet Plan

  • 15 foods to naturally lower blood sugar levels
  • 3 day sample meal plan
  • Designed exclusively by our nutritionist

By clicking “Download Now”, I agree to Ben's Natural Health Terms and Conditions and Privacy Policy.

What causes low blood sugar without diabetes?

Low blood sugar without diabetes only happens very occasionally. The following are causes of non diabetic hypoglycemia:

  • Reactive hypoglycemia or postprandial hypoglycaemia (this is when your body releases too much insulin after a meal)
  • Fasting hypoglycemia
  • Malnutrition
  • Gastric bypass surgery
  • Certain medications, such as quinine for malaria or antiviral hepatitis C medications
  • Other medical conditions (such as hormone problems, pancreas problems, liver problems, kidney disease, heart/blood flow and blood vessels problems, or adrenal dysfunction)

If you keep getting symptoms of low blood sugar, you should see your primary healthcare provider for medical advice about it. They will be able to run tests to find out your blood glucose levels and determine potential causes.

How to treat low blood sugar yourself

If your blood sugar levels on a blood glucose meter are less than 3.5 millimoles per Litre (70 mgdl), or you have symptoms of low blood sugar levels, then you can try treating it yourself.

First, try having a sugary drink or a snack. For example, have a small glass of fruit juice, three to six glucose tablets, or one to two tubes of glucose gel.

Retest your blood sugar levels ten minutes later. If they have not changed much, then have another sugary drink or snack. Test your blood sugar levels again in another ten minutes.

Once things have improved and you are feeling better, eat a meal. Make sure this meal contains a slow release carbohydrate. For example, you could have a slice of bread, a piece of toast, or a few crackers.

Once you feel better, you don’t usually need to seek immediate medical help. However, if you keep having instances of low blood sugar, then let your type 1 or type 2 diabetes team know. 

If you stop having symptoms to warn you that you have low blood sugar, it’s also important to let them know that. This is what we call hypoglycemia unawareness.

When low blood sugar is an emergency and what to do

If someone has severe hypoglycemia and then becomes very sleepy or unconscious, this is an emergency situation. This could be leading to diabetic ketoacidosis. Place them in the recovery position. Be sure not to place anything in their mouth, as this is a choking hazard.

If a glucagon injection is available to you and you know how to use it, administer it immediately. And if the person wakes up within ten minutes of the injection and feels better, see if they are fully awake. If they are able to safely eat and drink, then give them a snack containing carbs.

But if there is no glucagon available or you don’t know how to use it, then call an emergency line right away. If you gave the person glucagon but their condition did not improve within ten minutes, then call emergency services. Also, if the person consumed alcohol before the hypoglycemia, then you’ll want to call emergency services regardless of whether you gave glucagon or not.

If the person vomits or if their blood sugar levels drop, then they will require a visit to the hospital.

If you ever have hypoglycemia to the point of unconsciousness, tell this to your diabetes care team. It is important that they know.

Hypoglycemic seizure

If someone has a seizure or a fit due to low blood sugar, be sure to stay with them. Make sure to keep any hazardous objects away so that they don’t get hurt. Lie them down on a soft surface, if available.

If the seizure lasts more than five minutes, call emergency services. After the seizures ends, make sure they eat a sugary snack.

If you ever have an instance of low blood glucose levels that leads to a seizure or fit, share this information with your diabetes care team.


You should now have a good grasp of what low blood sugar is. You also know the early warning signs of low blood sugar to look out for. Importantly, you also have an idea of more serious symptoms to look out for in a serious case of low blood sugar. 

We also went over the causes of low blood sugar for diabetics to look out for. And you’re now aware of the potential causes of low blood sugar if you don’t have type 2 or type 1 diabetes. Yes, even non-diabetics do experience low blood sugar sometimes!

You also have the powerful knowledge of how to treat low blood sugar on your own. And probably the most important lesson in this entire article is what to do in a low blood sugar emergency situation.

If you experience symptoms of low blood sugar, be sure to reach out to your health care provider to discuss strategies for disease control and balancing blood sugar today.

Explore More

hypoglycemia diet

Hypoglycemia Diet: How to Prevent Low Blood Sugar.


  1. Cryer, PE. (1999). Symptoms of hypoglycemia, thresholds for their occurrence, and hypoglycemia unawareness. Endocrinol Metab Clin North Am. 28 (3), 495-500. https://pubmed.ncbi.nlm.nih.gov/10500927/ 
  2. International Hypoglycaemia Study Group. (2019). Hypoglycemia, cardiovascular disease, and mortality in diabetes: epidemiology, pathogenesis, and management. Lancet Diabetes Endocrinol. 7 (5), 385-96. https://pubmed.ncbi.nlm.nih.gov/30926258/
  3. Umpierrez, G & Korytkowski, M. (2016). Diabetic emergencies – ketoacidosis, hyperglycaemic hyperosmolar state and hypoglycemia. Nat Rev Endocrinol. 12 (4), 222-32. https://pubmed.ncbi.nlm.nih.gov/26893262/

Top Products

Total Health


Glucose Control