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7 Signs You Have Low Blood Sugar and Don't Know It

Learn the signs of low blood sugar. 

Low blood sugar happens when blood glucose levels drop below 70 mg/dL and while anyone can experience the condition, it's more common with people who have diabetes. When your blood sugar is low, chances are you won't feel like yourself, but you may not realize why. Eat This, Not That! Health spoke with experts who explain why it's easy to miss the signs of low blood sugar, symptoms to watch out for and why it's dangerous if left untreated. Read on—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.


Causes of Low Blood Sugar


Dr. Romy Block, a board-certified specialist in endocrine and metabolism medicine, member of the American Thyroid Association says, "Low blood sugar can be caused by not eating enough, malnutrition, pregnancy, rare cancers, and side effects of medications including diabetes medications." Laura McDermott MS, RDN, CD a Registered Dietitian Nutritionist and Certified Dietitian with RET Physical Therapy Group adds, "Certain medications can cause low blood sugar, many of which are used to help treat diabetes. Examples of these would be insulin or metformin when used with sulfonylureas. These medications may result in a low blood sugar when insufficient carbohydrate was consumed at the meal or the meal was skipped/delayed or consuming alcohol without food. People without diabetes or on medication may also experience low blood sugar and that can be from reactive hypoglycemia – not common and we do not fully understand why this happens to people without diabetes. Reactive hypoglycemia is where your body releases more insulin than needed after a meal, resulting in lowering your blood sugar too much. Fasting can create a low blood sugar when your body is trying to maintain homeostasis or when you run out of your glycogen stores. Low blood sugar can also be caused by intense exercise in some individuals."


What to Know About Blood Sugar

woman eating salad

Dr. Block tells us, "Blood sugar is what your body uses to process and produce energy. It is important to include healthy carbs in your diet like veggies, fruits and dairy to provide fuel to your body. Low blood sugar and skipping meals can cause fatigue." McDermott says, "When we discuss blood sugar, we are talking about glucose in the bloodstream. This glucose is an energy source for our body. Insulin helps get the glucose into our cells to be able to be used for our daily activities, from using your brain at work to running after the dog. Increases and decreases of blood sugar throughout the day is essential for optimal functioning. Glucose fuels your brain and your muscles. We just want to keep blood sugars within a healthy range, both on the higher and the lower ends."


The Dangers of Untreated Low Blood Sugar

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According to Dr. Block, "Low blood sugar can lead to severe symptoms including seizures, coma and death."


It's Easy to Miss the Signs of Low Blood Sugar

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Dr. Block explains, "Most of the time, people experience symptoms of low sugar, but they may not recognize those symptoms. This can include irritability, anxiety, palpitations, confusion and fatigue. The symptoms are nonspecific, so it is important to have regular meals and snacks with a healthy well-balanced diet. If symptoms do not improve with dietary changes, it is important to check in with your physician to help assess hypoglycemia. They may recommend advanced blood testing, a professional continuous glucose monitor or nutrition counseling."


Blurred Vision

Portrait of mature man with big black eye glasses trying to read book but having difficulties seeing text because of vision problems

Lisa Richards, a nutritionist and author of the Candida Diet shares, "Blurred vision is a symptom of low blood sugar due to water fluctuations in and out of the eye. As this causes the eye to change shape, vision can become blurred."



Portrait of a worried mature woman having problems with her finances

Richards tells us, "Confusion is a symptom of low blood sugar. This is a result of the brain not getting enough glucose to efficiently send signals to the body and fuel its cells."



Senior man buttoning his shirt.

According to McDermott, "The release of epinephrine when your blood sugar goes too low creates the shaky/trembling symptoms."



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Shutterstock / pathdoc

McDermott shares, "Changes in norepinephrine and epinephrine result in changes of the blood vessel behaviors which can lead to a headache."


Faster Heart Rate

woman having heart attack

McDermott tells us, "A faster heart rate is caused by the release of epinephrine (adrenaline) when blood sugar is low."



woman standing at fridge hungry and confused

McDermott states, "As blood sugars drop, your body produces hormones such as ghrelin to stimulate hunger so that you eat to maintain blood sugar levels."


Craving Sugar


Functional Medicine Dietitian Taylor Stolt, RDN, LD, CLT, IFNCP says, "If blood sugars are low your body is going to send a signal that it needs a fast form of energy aka sugar."


Heather Newgen
Heather Newgen has two decades of experience reporting and writing about health, fitness, entertainment and travel. Heather currently freelances for several publications. Read more about Heather
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