There are some things your bariatric surgeon probably won’t tell you about before he operates. For me, reactive hypoglycemia was one of those things. Instead of hearing about it at my surgeon’s information session or on the informed consent that I signed, I read about it online. Specifically, I first saw it mentioned by Melting Mama.

If you’re considering surgery, or, even if you’ve already had your surgery, it’s very possible that you’ve never heard of reactive hypoglycemia. But if you’re 18 months out or more from surgery, you likely have experienced a hypoglycemic episode. On the Obesity Help message boards, it’s very common to see posters asking about shakiness and dizziness approximately two to three hours after eating. That’s reactive hypoglycemia (RH).

What Is Reactive Hypoglycemia?

Reactive hypoglycemia is low blood sugar that typically occurs one to three hours after eating. Experts speculate that it is the result of an excessive insulin response. The body releases insulin in response to a carbohydrate meal, but the insulin response continues past the digestion of the meal and the disposal of the glucose derived from the meal. Symptoms may include shakiness, lightheadedness, sleepiness, anxiety, or confusion.

The Gastric Bypass Connection

Reactive hypoglycemia is common after gastric bypass surgery because of the lack of a pylorus. Following gastric bypass, food passes through the pouch via the stoma. In many cases, this can occur relatively rapidly, leading to quick absorption of carbohydrates in the small intestine. Under normal circumstances, the pylorus gradually introduces food into the small intestine. Following gastric bypass, the mechanism for moderation is removed, and food is “dumped” into the small intestine. This is the same mechanism behind dumping syndrome.

How Do I Treat Reactive Hypoglycemia?

The easiest way to manage reactive hypoglycemia is to eat several small meals throughout the day, typically every two to three hours. Meals should be balanced, including fat and protein as well as carbohydrates. Simple carbohydrates, such as sugar or grains, should not be eaten on an empty stomach.

If your blood sugar drops, it is crucial that you bring it back up quickly. The best way to raise your numbers is to eat simple carbohydrates. Glucose tabs are readily available at drug and grocery stores. Otherwise, juice or hard candies will work well. But, remember that consuming only those simple carbohydrates will set you up for another crash. To prevent that, follow the carbohydrates with a combination of protein and fat. Protein and fat regulate blood sugar levels, keeping them within normal ranges.

A blood glucose monitor is also a good resource for managing reactive hypoglycemia. When you feel the symptoms of reactive hypoglycemia, test your blood sugar. Technically speaking, hypoglycemia involves blood sugar levels under 70 mg/dL, though symptoms may not occur until levels drop below 60 mg/dL. Levels under 50 mg/dL can affect brain function and should be taken very seriously.

If you think you are experiencing reactive hypoglycemia, test you blood sugar levels before eating, one hour after eating, two hours after eating, and three hours after eating for a few days. If your numbers show a trend of low blood sugar in the postprandial period (the time after eating), reactive hypoglycemia is likely the culprit. Your blood sugar log will help your medical professional to reach a correct diagnosis.

At times, you can also experience the symptoms of reactive hypoglycemia without corresponding blood sugar levels. I have had textbook reactive hypoglycemic symptoms—shakiness, nausea, confusion—with blood sugar just above 70 mg/dL. My speculation is that the blood sugar dropped rapidly, and the symptoms are a response to the rapid drop, rather than to a low level. That’s just my hypothesis, though.

The Bottom Line

Normal blood sugar levels are crucial to your body’s function. In extreme circumstances, reactive hypoglycemia can lead to neurological problems, including seizures. If you believe that you are experiencing low blood sugar levels, take responsibility for your own health. Start testing your levels and treating any low episodes. You and you alone are responsible for your health after bariatric surgery. Take it seriously.

Sources:

• Mayo Clinic
• Reactive Hypoglycemia Info
• Brun, J.F., Fedou, C., and Mercier, J. (2000) Postprandial reactive hypoglycemia. Diabetes & Metabolism, 26, 337-351.