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No Calories Today

People with diabetes can do almost anything anyone else can. Whether it is championship biking, mountain climbing, dare-devil skiing or whatever the latest and greatest new activity is, people with diabetes can generally find a way to do it.

But what about fasting? No athletic special effects here, just simple denial of nourishment. We know that it is possible to manage the decision to eat a bit too much food on occasion, but is it possible to skip eating all together? Is it dangerous? What will happen if you don’t eat? Should you continue to take your medicine?

People fast for all sorts of reasons, from religious commitment to medical procedures to beliefs about the cleansing power of fasts. As a matter of fact, most religions don’t require people whose health may be put in jeopardy to fast. For example, in the Muslin religion, the Koran specifically identifies groups of people who are exempt from fasting. This includes children, pregnant or breastfeeding women, the elderly and anyone who might make themselves ill by fasting. Still, many people consider it their duty to fast as a sign of commitment to their religion. I am going to stay out of that boondoggle and just say that having diabetes gives you a pass; no fasting is required on religious grounds.

Let’s look at what happens when you do fast. The body stores energy in two forms: glucose and fat. Glucose is stored in muscle cells as glycogen. Additional glycogen is stored in the liver. For a 150-pound man, the combined calories of all glycogen stores are approximately 1,800 calories. There is only a couple days worth of calories available in glycogen stores and a normal overnight fast depletes the body’s glycogen stores approximately 50 percent. Once that is gone the body has to make more glucose through a process known as gluconeogenesis in which amino acids are converted into glucose.

When you don’t eat, the pancreas doesn’t secrete as much insulin. After all, there isn’t much glucose for the insulin to work with. Low insulin levels stimulate the liver to release glucose in order to keep the glucose level in the blood in the target range. The low insulin levels also promote the breakdown of stored fat. Even though fasting burns calories, it doesn’t do it efficiently because the body starts to conserve fuel by slowing your metabolism.

When you have type 2 diabetes, the same processes occur when you fast. The difference is that many people with type 2 diabetes take medications called oral hypoglycemic medications or insulin. These agents continue to work even if you don’t eat anything, which, as you know, can put you at risk for low blood glucose.

Given the risks, fasting unless medically required probably isn’t your best bet, but....if you decide you do want to fast:

* Talk with your doctor. You should do this far in advance of your decision to fast so you and your physician can discuss any changes to the medications you take. It is still important to take your medicines, but depending on the type of medicine, perhaps not as much.

* Check your blood glucose frequently during periods of fasting. It is better to catch low blood glucose before it happens, than be faced with a trying to treat a glucose level of 30mg/dl.

* Make sure you are well hydrated before you begin the fast. Dehydration can cause your glucose levels to rise quickly.

* Keep easily available carbohydrate nearby for possible hypoglycemia – if your blood glucose gets too low, you will need to discontinue the fast.

* Break your fast with a light meal; overeating can quickly lead to hyperglycemia (high blood glucose).

* Think twice about fasting if you are elderly or under-the-weather — these aren’t the times to further stress your body.

Live well and enjoy!


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