Managing your blood glucose (sugar) levels with type 1 diabetes or type 2 diabetes can feel like a balancing act.
You don’t want your blood glucose to be too high, nor do you want it to be too low.
Unlike high blood glucose levels, which often don’t have symptoms, low blood sugar is associated with several common symptoms.
Being aware of low blood sugar symptoms can help you quickly identify low blood sugar and treat it promptly. The quicker you can treat low blood sugar, the less likely you are to experience complications from it.
What are low blood sugar levels?
Insulin levels primarily influence your blood sugar levels. Insulin is a hormone that helps blood sugar enter your cells from your bloodstream. Too much insulin can cause low blood sugar.
A normal blood sugar range is between 70 and 140 mg/dL. It can become problematic if your blood glucose level consistently falls above or below this range.
A low blood sugar level is defined as being less than 70 mg/dL. Having low blood sugar (blood glucose) is called hypoglycemia. You might not feel symptoms of a low blood sugar level until it falls below that threshold, or you might feel symptoms at a slightly higher blood sugar level.
When you feel low blood sugar symptoms will depend on several factors such as how long you’ve had diabetes, your normal blood glucose level, history of low blood glucose, and more.
Why are low blood sugar levels dangerous?
Hypoglycemia is broken down into different levels of severity.
Level 1 (mild) hypoglycemia
Blood glucose is less than 70 mg/dL but is 54 mg/dL or higher.
Level 2 (moderate) hypoglycemia
Blood glucose is less than 54 mg/dL.
Level 3 (severe) hypoglycemia
A person cannot function because of mental or physical changes, and they need help from another person. In this case, blood glucose is often below 40 mg/dL.
Hypoglycemia can become dangerous at any range, but it’s especially dangerous when it drops below 60 mg/dL.
Most people will experience low blood sugar symptoms once their blood sugar level falls below 70 mg/dL. Some people have hypoglycemia unawareness which is when they don’t feel low blood sugar symptoms as soon as they should.
Hypoglycemia unawareness can lead to severely low blood sugar. The main risk factor for developing hypoglycemia unawareness is having repeated low blood sugar incidents in the past. The more often you experience low blood sugar, the less likely your body will respond to low blood sugar symptoms.
Some risk factors for developing hypoglycemia include:
- Use of certain diabetes medications that lower blood sugar, especially insulin.
- Heavy exercise
- Erratic eating patterns/skipping meals
- Advanced age
- Weight loss (improves insulin sensitivity so can lower blood sugar)
- Drinking alcohol
- Having advanced kidney disease
So why is low blood sugar dangerous? Untreated hypoglycemia can lead to seizures, loss of consciousness, coma, and death.
Low blood sugar can also contribute to falls, injuries, and car accidents. Low blood sugar is linked with a greater risk of dementia in older people.
10 signs of low blood sugar
Some people experience nocturnal hypoglycemia, which is when low blood sugar occurs overnight while you’re sleeping. Nocturnal hypoglycemia is potentially even more dangerous because you aren’t awake and alert, so you likely won’t notice low blood sugar symptoms.
Signs of nocturnal hypoglycemia include:
- Damp sheets or nightclothes from sweating due to low blood glucose
- Having nightmares
- Feeling tired, irritable, or confused after you wake up.
Sweating is a general low blood sugar symptom that can occur while you’re awake as well. You might feel clammy and sweaty even if it’s not hot out if your blood glucose level is falling.
When glucose can’t get into your cells, they don’t have the energy they need, which can cause fatigue.
You might also feel tired when your blood glucose level is high, so you’ll want to check your blood sugar when you’re feeling tired to know what’s going on.
Similar to hypoglycemia, you might feel tired when your blood sugar is high because sugar cannot enter your cells to provide energy.
Cells are starved without enough glucose to feed them. If you’re experiencing low blood sugar, you might notice you feel hungry as a response.
Along with sweating and hunger, shakiness is a common low blood sugar symptom. When your blood glucose level falls, your body releases stress hormones such as epinephrine (adrenaline) and norepinephrine to raise your blood sugar. These hormones can cause tremors and feelings of shakiness.
5) Rapid heartbeat
Low blood sugar causes your body to release stress hormones. These stress hormones (including adrenaline) cause anxiety symptoms, such as increased heartbeat.
6) Feeling irritable
Extreme blood sugar changes can trigger anger, moodiness, or sadness in some people. Mood changes might not be as accurate as other physical symptoms, so you should always check your blood sugar to be sure.
7) Tingling lips
It’s not exactly clear why tingling lips are a symptom of low blood sugar, but you might notice tingling in your face or lips if you’re experiencing hypoglycemia.
8) Brain fog
Your brain needs glucose for fuel. If your blood glucose level is low, your brain doesn’t have enough energy to function correctly. This can result in “brain fog” or feeling like you can’t think straight or focus well.
9) Clumsy movements and confusion
Severe hypoglycemia can make you appear drunk even if you haven’t had any alcohol.
Slurring your speech, stumbling, and not making sense when you talk are all low blood sugar symptoms that you shouldn’t ignore.
10) Vision changes
Low blood sugar can cause blurry vision or double vision. You can also experience vision changes when your blood sugar is high, which is why checking your blood sugar at the onset of low blood sugar symptoms is so important.
How to manage your blood sugar levels
Check your blood sugar level regularly.
The best way to become familiar with your blood sugar trends is to check your blood glucose. Checking your blood glucose regularly will help you identify how you respond when your blood sugar is high or low.
People who check their blood sugar regularly tend to have better blood glucose control compared to those who don’t.
Take medications as prescribed.
Certain diabetes medications can cause low blood sugar. The most common diabetes medications with a risk of hypoglycemia are insulin and sulfonylureas. Avoid changing your medication doses on your own, which might cause low blood sugar.
Insulin is the most effective medication at lowering blood sugar, which is why it comes with a risk of hypoglycemia.
Be ready to treat low blood sugar.
Mild low blood sugar can be treated with fruit juice, glucose tablets, and hard candies. If you’re prone to low blood sugar or take insulin, keep these things on hand at home, in your car, at work, and while out exercising.
More severe low blood sugar is treated with a glucagon injection. Glucagon is a hormone that helps raise your blood sugar. You need a prescription for glucagon, which is an injectable medication.
Eat carbohydrates consistently.
Carbohydrates are a type of nutrient that raises blood glucose levels. Try to eat carbohydrate meals and snacks consistently throughout the day to promote stable blood sugar.
Eating a carbohydrate-heavy meal and then a very small carbohydrate amount at the next can cause blood sugar spikes and crashes.
Be mindful of how exercise impacts your blood sugar.
Exercise can help lower blood glucose, so it’s so beneficial to help manage your diabetes. If you exercise on an empty stomach, you might experience low blood sugar. Aim to have a meal or snack around one hour before exercising to avoid low blood sugar.
If you have type 1 diabetes or type 2 diabetes and are taking insulin, you’ll likely experience hypoglycemia at one point or another.
Mild hypoglycemia usually doesn’t result in serious complications, but it can turn into severe hypoglycemia if left untreated.
Being aware of low blood sugar symptoms is the best way to prevent health issues that can arise from more serious low blood sugar.