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Losing it

Is fasting a healthy way to reboot the system?


What would you like to change about your health in the next 30 days? A persistent pot belly? Back-to-back colds? Allergies, poor skin, constipation, gas?

Chronic generalized blah-ness? If you wish you could hit the reset button and get your mojo back, some believe the way to do that is through fasting.

Starting fresh by stopping eating

Proponents argue that we should think of ourselves as a useful machine, say, a dishwasher. When the dishwasher is smelly with stuck-on grime, you stop loading it, add detergent, shut the door and hit “wash.” That’s what a fast is, according to those who swear by the process. Some products claim that you can cleanse by swallowing a couple of capsules called something like Kleengut Now! while the waiter is taking your usual nachos order. Those who believe in fasting say that’s a no-go and that all true internal cleansing is done in the same way: by abstaining from eating for a time.

While many people may feel like they are going to die if they miss lunch, periodic fasting has actually been a way of life in some cultures and has been practised as a discipline for at least 5,000 years. Religious observances such as Ramadan, Yom Kippur and Lent, for example, include periods of fasting. The late Allan Cott, M.D., whose 1977 book, Fasting as a Way of Life, is on my kitchen reference shelf, starts with a clarification right on page two. “Fasting is not starving. The body has in reserve a . . . supply of food. It nourishes itself during a fast as if it were continuing to receive food.”

Storing fat?

Thirty-seven years later, my personal experience still bears this out, although some more recent opinions have given me pause. David Lau is an obesity researcher at the University of Calgary. He argues that glycogen stores in the liver are depleted during fasts – and that’s a bad thing.

What’s glycogen? Here’s the short answer. The body breaks down most carbohydrates in foods and converts them to glucose, which gives our cells fuel. Glycogen is extra glucose stored in liver and muscles and is made up of many glucose molecules. When the body needs quick energy or it isn’t getting glucose from food, glycogen releases glucose into the bloodstream. But when glycogen stores in the liver are depleted, the body doesn’t burn fat: it breaks down protein – and that’s not healthy.

Weighing the risks

When glycogen stores in the liver are depleted, the body doesn’t burn fat: it breaks down protein – and that’s not healthy

Ottawa dietician Nicola Day is also skeptical of fasting. “There are some risks, medically and nutritionally, associated with cleansing regimes,” she says, citing side effects such as low blood sugar, muscle aches and light-headedness. “There is no good evidence that detox diets are actually detoxifying; the body has systems in place to do that.”

Some researchers, however, do see an upside to temporarily keeping food at bay. “Given the North American lifestyle and diet, we are incapable of maintaining a level of good health,” says Victoria family doctor Brian Pound. “Obesity is rampant even in children, so this kind of cleansing may contribute to better overall health by undoing the damage that has been caused by a poor diet.”

As well, Mark Mattson, senior investigator for the National Institute on Aging in the U.S., says fasting has been shown to improve biomarkers of disease and preserve learning and memory functioning.

All in moderation

Moderation is key, everyone agrees. Fasting for a day or two isn’t likely to be a problem if you’re healthy, but doctors say you may experience some side effects, such as insomnia, irritability, bad breath, anxiety and exhaustion. What’s more, going without food for even that short a period of time can be dangerous if you’ve got liver or kidney problems, a compromised immune system or are on medication – even Tylenol. And it’s really important to know when fasting turns into starvation.

An informed choice – and a game plan

The basic difference between starving and fasting is that fasting is a choice. You can be forced to starve but not forced to fast. There’s a real risk in taking fasting so far that it turns into starvation. Doing so can be deadly.

My own caution is about what happens after a cleansing fast. It’s extremely important to have a refeeding program that lasts as many days as the cleanse itself. Refeeding means fasters should limit their calories and avoid overindulging. Experts say it’s best to gradually step up caloric intake over the next week if the fast lasts for a few days. As well, allow the newly found vigour you may experience to inspire you to keep eating properly. ◊