I’ve done a lot of fasting in my life. I’ve written a lot on it, too. This is one of the simplest scientific explanations about it I’ve seen. I gives you some science and minimizes the confusion. Here’s an excerpt:
“Glycogen is necessary for thinking; it’s necessary for muscle action; it’s necessary just for the cells to live in general,” says Dr. Naomi Neufeld, an endocrinologist at UCLA.
Neufeld says most adults need about 2,000 calories a day. Those calories make energy, or glycogen. Neufeld says it doesn’t hurt — it might even help the body — to fast or stop eating for short periods of time, say 24 hours once a week, as long as you drink water.
“You re-tune the body, suppress insulin secretion, reduce the taste for sugar, so sugar becomes something you’re less fond of taking,” Neufeld says.
Eventually the body burns up stored sugars, or glycogen, so less insulin is needed to help the body digest food. That gives the pancreas a rest. On juice diets recommended by some spas, you may lose weight, but your digestive system doesn’t get that rest.
Mark Mattson, a scientist with the National Institute on Aging, says that when we convert food into energy, our bodies create a lot of byproducts we could do without, including free radicals.
“These free radicals will attack proteins, DNA, the nucleus of cells, the membranes of cells,” Mattson says. “They can damage all those different molecules in cells.”
If you don’t want to read, there’s also an audio link. Enjoy.