DEAR DR. BLONZ: I have a question about fasting as a means to help release toxins from the body. I have used fasting in the past to help jump-start my weight loss, but I have also read that it helps with toxins. Is this true? -- S.H., Seattle
DEAR S.H.: Some connect the way they feel during a fast as an affirmation that their body is casting off toxins. This can be misleading, as the lack of food can cause sensations that might be mistaken for such an effect.
It is a bumpy road to assume that fasting facilitates healing through the removal of toxins. Detoxification is an ongoing process in our bodies. Our digestive system is designed to keep nasty stuff from gaining entry, while the liver and excretory systems work to neutralize and get rid of “undesirables” in the body. Stopping the intake of healthful foods can handicap detoxification by curtailing the raw materials that facilitate the process. With no food coming in, metabolic priorities get reshuffled.
Humans evolved amidst unreliable food sources; we made it through such stresses thanks to our ability to use stored energy in different ways, and thus keep our brains working and muscles fueled until we could find new food sources and increase our chances for survival.
Fat storage cells in our body (adipocytes) shrink in size during a fast, as their contents provide energy for the body. Some types of toxins accumulate in the fat cells because many problematic toxins are fat-soluble, and our fat storage is our largest depot to dilute these contaminants. The body slowly eliminates toxins during the normal cell turnover, as all cells are routinely taken apart and remade.
During a fast, the blood levels of some toxins can rise. Think of this as putting a dirty sponge in a pan of water, where the water is slowly but continually refreshed. Over time, the dirty sponge gets rinsed clean. Now, think of how squeezing a dirty sponge in the pan would have an immediate effect on the water.
If the body could easily eliminate stored toxins, they wouldn’t have built up in the first place. Now, also consider that with a fast, your body no longer has the fuel and other nutrients to keep things going. Heavy metals, for example, can only be slowly eliminated from the body, and they create a problem if the intake is greater than our ability to eliminate them. They must get stashed away to keep them from causing metabolic harm. During a fast, the reduction of body mass can release more of these into the system.
The other aspect of fasting you mention is the “jump-start” phenomenon, and this deserves consideration. Here, one can use the fast as a transition period to jettison past practices before shifting to a new lifestyle -- ideally a more physically, emotionally and spiritually healthful one. There is potential here, as the fast might serve as a productive time of contemplation to review the status quo and make new plans. It can be a powerful tool as it defines a distinct separation from what was and what is to be. But it should be approached cautiously, especially if there are ongoing health considerations and medications, so be sure to check with your health professional.
Send questions to: “On Nutrition,” Ed Blonz, c/o Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to email@example.com. Due to the volume of mail, personal replies cannot be provided.