Fasting

In response to a comment to a previous post, this is a post 

about fasting. I don't claim to be any kind of expert; this is just me trying to apply common sense and the sum of whatever I've gleaned about nutrition to sift through the contradictory information that's out there on this subject.

 

For transparency's sake, I'll start by saying:

-         I am generally biased against anything I perceive to be a fad diet popularized mainly as a means of losing weight. Nothing will ever come down the pike that beats eating appropriate portions of healthy foods and exercising, in my view.

 

-         I am generally biased towards cultural practices that have withstood the test of thousands of years, and culturally biased towards periodic fasting from growing up Hindu. Periodic fasting is definitely encouraged by Hindu spiritual teachers. Once I turned 18 or 20, Swamiji used to say, why don't you begin fasting once a month? I have never maintained that monthly practice, but many people in my community do. I will, however, fast on particular holidays, which amounts to a few times a year.

 

-         My definition of fasting: attempting not to consume anything caloric between sunrise and sunset – you're allowed water and tea (just brewed tea – no milk, no lemon), and if you're feeling extremely headachey around 4 o'clock, hypothetically, I wouldn't tell if you had a glass of diluted juice : ).

 

-         In discussing fasting, I am not talking about Gandhi's quasi-suicidal weeks-long fasts; we're talking a single day, not more than one a month. The month of Ramadan would be as far as I'd go in terms of condoning the practice, again favoring a somewhat tested cultural practice. 

-         The real reasons to fast periodically might very well mainly be cultural and religious, and that's perfectly ok too. We're human beings; we're bodies and spirit. There might occasionally be things we do for the sake of the spirit. (As long as we're healthy and not self-destructive.)

 

So, what's the sum of what we "know," whether from science or from cultural tradition?

 

-         People in many cultures have practiced periodic fasting for thousands of years.

 

-         From an evolutionary perspective, our food supply was not always so reliable, so we have probably evolved some coping mechanisms to deal with brief periods of scarcity.

 

-         Fasting can discipline the will to say no to food; over time, practicing periodic fasting might make choosing the right foods and rejecting the wrong ones easier. However, especially at first, people who try fasting find themselves gorging the next day. This is why fasting is an ineffective and even dangerous weight loss tool.

 -         Short-term fasting might train (healthy) cells to withstand stress better and might re-sensitize insulin-producing cells.  

o       When healthy cells are starved, the body enters into ketosis, or using up stores of glucose and burning fat, to keep your organs and brain functioning. Cells shift into a protective survival mode and activate cellular repair mechanisms. Understanding this mechanism has caused some experimental individuals to adopt a very aggressive calorie restricted diet in pursuit of longevity.

o       One of the mechanisms for acquiring type 2 diabetes is increasing insulin resistance. Giving the body a break from constant glucose exposure might re-sensitize insulin-producing cells.

 

Here's the great big "but":

-         The scientific evidence that periodic fasting is affirmatively healthful is mostly derived from studies on mice and rats. We don't really know if it works for us. Our brains are much bigger and much bigger consumers of glucose than most other animals, and each of our brain cells is sheathed in insulating fat.

 

Finally: You should definitely not attempt fasting:

-         if you've got liver or kidney problems (hepatic or renal insufficiency)

-         if you're immunocompromised

-         if you're on medication – even Tylenol

-         if you're pregnant

-         if you have a wasting disease or malnutrition

-         if you have a history of cardiac arrhythmia

-         if you're obese

-         if you have type 2 diabetes

-         etc.

 

 

So, to apply some of the above to what my commentator specifically asked about, the "Master Cleanse"...

 

The Master Cleanse is a "detox juice diet" that is supposed to "cleanse" harmful toxins from the body and cause the body to shed excess weight. It also supposedly ends cravings for habit-forming beverages like coffee and tea. While on the diet, you drink fresh lemonade with cayenne sweetened with a very unprocessed, pure maple syrup and eat no solid food, for 10-30 days. Constipation is an issue while on this liquid diet, so people also take laxative teas. 

To me – other than the claim about reducing dependence on caffeine, which makes sense simply because not consuming caffeinated beverages will have this effect – the Master Cleanse sounds like an extremely specious practice.  A fad diet.

 

Ten to 30 days is a very long time to go without proper nutrition. In fact, it seems to me that this "Master Cleanse" allows people essentially to fast for a very extended period, by providing a few calories, vitamins, and minerals via the lemonade. So you limp along in what's basically a fast by imbibing a little glucose and vitamin C.

 

Most physicians and scientists will tell you that the body does an excellent job of "detoxifying" itself: that's what our skin, lungs, kidneys, liver, spleen, and digestive system are for. Phytonutrients (from eating vegetables and fruits) can actually help us to "detoxify." Some toxins are stored in our fat cells, so activating the burning of those fats through short-term starvation might be one aspect of the "cleanse" that makes sense, but that is a very extreme way to do it, and there are healthier ways to activate fat burning (exercise, for instance, and more moderate calorie restriction).

 

A side effect of the Master Cleanse would be the decreasing of the populations of healthy gastrointestinal bacteria we live in symbiosis with. At the end of the "cleanse," when reintroducing food, you'd have to add probiotics to help repopulate your gut with healthy bacteria.

 

In fact, the best way to rid the body of pesticides, hormones, prescription drugs, chemical fertilizers, heavy metals, and other toxins is probably just to stop consuming them; follow a natural, healthy diet of mostly vegetable origin; and allow the body to do its job.

 

Then again, there are individuals who swear by the Master Cleanse, who claim it gave them permanent weight loss, increased energy, clear skin, better vision, decreased joint pain and so on. It's quite possible many of these people were eating quite a bit of junk before going on the "cleanse," so it might have been the absence of bad foods rather than the "cleanse" itself that helped. And there's always the placebo effect.

P.S. I don't even enjoy writing about dieting/the Master Cleanse... and definitely wouldn't put it into the genre of this blog. But I do enjoy receiving and responding to posted comments : )