Many of us have had that feeling of feeling tired, shaky or even anxious that people often identify as low blood sugar. But is that feeling really related to blood sugar? Do healthy people really get low blood sugars? And are we all even talking about the same thing?
First, a caveat: People taking insulin and/or some oral medications for diabetes can get dangerous low blood sugars. That is not what we are talking about today and it should be discussed with your primary care doctor, endocrinologist or diabetes educator.
However, many people without diabetes experience the uncomfortable symptoms associated with low blood sugar. The vast majority of these symptoms are caused by a normal change in blood sugar called “postprandial hypoglycemia” meaning low blood sugar after eating.
Signs of postprandial hypoglycemia include feeling especially tired and then shaky and sweaty 1-2 hours after eating carbs. Some people will feel a strong craving for sugar or other simple carbohydrates. The symptoms often improve if one eats carbs.
However, if you check the blood sugars when symptoms are present they are typically normal. Why does this happen?
When we eat foods that contain carbohydrates, the amount of glucose in our blood rises and falls. If we eat a lot of simple sugar (soda, juice or candy) it rises and falls quickly. If we eat complex carbohydrates it rises and falls more slowly and typically never rises as high. When blood sugar falls quickly it can cause the symptoms described above. Some people are more prone to symptoms than others.
So what can you do if you experience postprandial hypoglycemia?
First try modifying your diet. Foods high in refined carbohydrates are more likely to cause symptoms. Avoiding those foods can minimize symptoms for many. When you do eat foods high in simple carbohydrates, be sure to pair them with proteins or healthy fats–Avocado toast or apples with no sugar added nut butter. Working with a dietician to identify troublesome foods can be helpful for some people.
If you do get symptoms, try treating them with a mixed snack like a handful of nuts or cheese and crackers.
In cases where symptoms are severe, there are supplements and even medications that can help minimize symptoms, so it is worth talking to your doctor.
I review hypoglycemia in greater detail here, if you are interested.