ZocdocAnswersHow do you know if you have low blood sugar?

Question

How do you know if you have low blood sugar?

I have a weak feeling that I thought was coming from not eating enough. But lately I am eating better but still have a weak feeling. Is this from my blood sugar? How can I tell if my blood sugar is too low?

Answer

I suggest that you go to see your primary care doctor about this especially since it seems like the symptoms have been going on for some time. It is actually kind of a medical myth that low blood sugar is the cause of these kinds of symptoms. Although it certainly is true that some people will faint or weak if they have not eaten in a long time, this is not because their blood sugar actually goes low. In fact, low blood sugar almost never occurs unless you are diabetic and taking medications like insulin to lower your blood sugar. There are a few medical conditions that can cause low blood sugar outside of this setting, such as tumors that produce insulin, but these are extremely rare. Therefore, it would be a good idea to get a complete checkup from your primary care doctor. In addition to an examination, they will be able to perform basic blood work to see if there is obvious cause of your weakness and fatigued feeling. For example, these symptoms are often caused by a condition called hypothyroidism, where the thyroid gland is under active, and this can be picked up with simple blood tests. Get in to see your doctor at your earliest convenience.

This answer is for general informational purposes only and is not a substitute for professional medical advice.

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