11 Warning Signs Of Low Blood Sugar Doctors Want You To Know About

Anxiety, brain fog, and more low-key signs.

by Carina Wolff and JR Thorpe
Originally Published: 
A woman with braids lies facedown in bed. This article details warning signs of hypoglycemia doctors...
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If you get the tremors and feel decidedly tired and grumpy when you haven't eaten for a while, you may just be getting hangry — or you could have hypoglycemia, the technical term for very low blood sugar. Although it's most common in people with diabetes, it can occur for other reasons as well, and there are distinct warning signs of hypoglycemia that you can look out for. Low blood sugar can cause both short-term and longer-term complications, making it important you know what bodily changes could signify the condition.

Blood sugar is the amount of glucose in your blood at any given time, and it's pretty crucial to your health. Glucose fuels your body, including your muscles and brain, and is a major source of energy. When it dips to low levels, you'll definitely start feeling it.

"Hypoglycemia typically relates to a blood sugar less than 60 for most people," says Dr. Heather Bartlett M.D.. "However, some people that are unknown diabetics or are pre-diabetic may be living at a higher blood sugar all the time, above normal, so even a drop to what is considered normal for most people could provoke a symptom of hypoglycemia."

Dr. Katherine Araque, M.D., an endocrinologist at Providence Saint John's Health Center, tells Bustle that there are two types of hypoglycemia symptoms: neuroglycopenic ones, which are caused by the brain being deprived of glucose, and neurogenic ones, which are caused by adrenaline rushes. When you're hypoglycemic, your brain produces adrenaline to tell your liver to make more sugar, and that can make you jittery as hell. Think of it a bit like a panic attack, accidentally kicked off by your liver.

In addition to diabetes, hypoglycemia can be caused by diet, certain medications, hormone or enzyme deficiencies, and more, according to Harvard Health. Discovering signs of hypoglycemia can help you get treated for any underlying medical issues and prevent possible damage.

If you're feeling off and think your blood sugar might be to blame, watch out for these 11 warning signs that could mean you're hypoglycemic.



"Each person's individual reaction to low blood sugar may vary," Dr. Neal Shipley M.D., medical director at Northwell Health GoHealth Urgent Care, tells Bustle, but tiredness is pretty common. Glucose is a big source of energy for your brain; without a lot of sugar in your blood, it'll lack get-up-and-go, according to the U.S. National Library of Medicine. When you're hypoglycemic, your brain doesn't have enough blood sugar to fuel its activities, so you'll likely start feeling like you need some ZZZs immediately.


Irritability & Anxiety

"Some people may experience feeling anxiety [during hypoglycemia]," Dr. Becky Koickel, M.D., associate medical director at Northwell Health GoHealth Urgent Care, tells Bustle. This, Dr. Araque says, is a neurogenic symptom, where adrenaline rushes through your brain. It can cause severe mood swings or anxiety, or it could even be something as mild as general irritability or feeling easily annoyed. Suddenly your housemate's breathing might sound really aggravating.



Headaches from hypoglycemia are usually described as a dull, throbbing feeling in the temples, and Dr. Koickel says that's pretty common. Low blood sugar can also trigger migraines (yeesh), but they're not usually accompanied by the usual nausea, vomiting, and sensitivity to light and sound. Instead, this variety of migraine comes with other symptoms of hypoglycemia, like blurry vision, fatigue, irritability, and confusion.


Constant Hunger

Hypoglycemia can make you feel like you need to devour everything in your fridge. Dr. Araque says that when you have low glucose levels, your body starts releasing glucose from your liver and craving food to replace it. Eating can usually help raise blood sugar (though maybe don't go for the old pickles that expired in 2017).


Heart Palpitations

"One of the most common symptoms of hypoglycemia is feeling like your heart is pounding," Dr. Shipley says. Blame this one on adrenaline, too; as it courses through your system, it can cause a rapid heartbeat and heart palpitations. If you find that your heart is racing more than normal, your blood sugar might be bottoming out.


Cold, Clammy Skin

Hypoglycemia can also affect the look and feel of your skin. When your blood sugar drops, your face can become cold and pale, according to University of Michigan Medicine. This is a side effect of adrenaline as well; your blood is being diverted away from the surface of your skin to vital organs, making you look like Edward Cullen.


Brain Fog

Yep, hypoglycemia can also cause a brain fog. Your brain needs glucose for fuel, Dr. Araque says, so it can't perform properly, leaving you feeling dazed and confused. Dr. Koickel says you may also experience blurry vision alongside your confusion. Math problems no; naps, yes.



"Dizziness and lightheadedness," Dr. Shipley says, can occur as a result of low blood sugar. This is on the extreme end of symptoms, and it's often accompanied by confusion and fatigue. You could even start acting oddly drunk, despite not going near alcohol.


Tingling Sensation Around The Mouth

If your mouth or lips are tingling, you might be experiencing hypoglycemia, according to Harvard Health. You might also feel tongue numbness or metallic taste in the mouth. It's not entirely clear why this happens, but Cedars Sinai Hospital notes it's possible that the nerves in the mouth and tongue react poorly to low blood sugar.



Feeling anxious and sweaty is a common symptom of low blood sugar, Dr. Shipley says. If you start feeling unusual sweating that may be later accompanied by chills, it may feel like you're having a sweaty panic attack, but it's a common reaction to adrenaline. It can occur all over the body, not just on the armpits, and it can progress from mild to drenching. Deodorant to the rescue.



Shakiness, Dr. Koickel says, is one of the classic early signs of hypoglycemia. When your blood sugar drops, you may get some shakiness along with your anxiety and fast heart rate. It's all part and parcel of your body's adrenaline response. This can be really scary, but it's likely to fade as soon as you get your blood sugar up again with some food.

"Always consult with your endocrinologist and primary provider if you suspect you're suffering of symptoms suggestive of hypoglycemia," Dr. Araque says. They'll help you sort it out post-haste.


Dr. Katherine Araque M.D.

Dr. Heather Bartlett M.D.

Dr. Betsy Koickel M.D

Dr. Neal Shipley M.D.

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