My diet revolves around eating cycles. For 24 hours I eat...and for 24 hours I fast.
This is by no means meant to be absolute, do or die, but an ideal to strive for—not to get upset about if I fall short of the mark, and I am free to make adjustments. I can easily turn this into a 20-hour fast, or a 36-hour fast.
I am aiming for three 24-hour fasts a week. Ideally the end of each fast will fall on Tuesdays, Thursdays, and Saturdays, but I'm open to adjustments if/when necessary. Sundays will be an off day, in which I can eat at my leisure throughout.
Today, for instance, I'm eating through the day until 3 P.M., at which point I'll fast until 3 P.M. tomorrow.
After 3 P.M. tomorrow, I'll eat until about 9 P.M. Only sleep will divide my last meal at night and my first meal in the morning.
At 3 P.M. of the third day, my fast begins anew.
Why would I want to fast at all?
For me personally, the reason I fast is simply because fasting feels great. I have a ton of physical energy, and mentally I feel very peaceful and serene. This means that while my body feels invigorated, I also feel spiritually invigorated. There's much more of a mind-body connection during a fast.
Fasting is a great opportunity to work on my practice of awareness, practicing making conscious decisions. This can be viewed on a spiritual level, but also on a practical, everyday level because the practice I get while fasting lends itself to the times when I'm not fasting, when I may be more susceptible to stress—in which case I can better choose not to give into my reactions, whether they're emotional (depression or anger) or physical (having a craving for ice cream).
Mentally I have never felt depressed in a fasting state. I have felt little to no anxiety, and what anxiety I've had has been very manageable. I experience less anger, and feel less concern for the usual emotional triggers that usually, when I'm full of food, would drive me to be overly angry or sad or worried. Eating becomes my biggest worry, and that's no worry at all.
There are negative side-effects to fasting.
It may sound strange to hear, but my biggest difficulty with fasting isn't going without food, but eating. I'm trying to gain weight, but by fasting I'm giving myself less time to feed. I must overeat 2,500-3,000 calories in a short amount of time, which can make me feel sluggish and edgy (even hostile, which defeats the purpose). The remedy to this is to deviate from the 24-hour routine. I can ether shorten each fast to 20 hours (eat for 28 hours and fast for 20) so that I have a larger eating window, or lengthen the fast to 36 hours (alternate-day fasting) in order to have a full day to eat at my leisure.
The 20- and 36-hour fasts are variations of a theme, and provide the same benefits as a 24-hour fast but to different degrees.
I have to be very careful about how much water I drink. Obviously during fasting water is a necessity and my body functions better and I can think more clearly if I am drinking water continuously, but water is at least as important while I'm eating. I can get just as dehydrated during my eating cycle as I can my fasting cycle if I neglect water.
While my physical and spiritual energy rise (along with my creativity), my mental concentration and raw ability to focus on anything but my body are diminished. Any writing I want to do must be done early in the morning, as soon as possible, because by the last several hours of my fast I don't have much of an attention span left.
There are numerous health benefits to fasting, and if you've related to what I've written above, or have found what I've had to say interesting, please read on. But keep in mind that I put less emphasis on the experimental data—the claims of detoxification, longevity, and reduced risk of disease—as I do on how fasting makes me feel, because whereas data is abstract, how I feel is concrete in the sense that I can feel it, and do not merely have to hope it's true.
Perhaps there is a link between the way fasting feels and its health benefits, but let's put that aside for now and look at the claims.
From the research I've read in the last few years I've found that intermittent fasting has been studied and shown to lower the risk of all major forms of disease—the big killers—heart disease, diabetes, and cancer, but also helps with some auto-immune disorders by reducing inflammation.
See http://ajcn.nutrition.org/content/86/1/7.full and http://www.naturalhealth365.com/natural_cures/fasting.html
My favorite theory as to why fasting is so beneficial is that fasting allows a major function of the body—the digestive system—to rest.
We sleep, resting our conscious mind and bodies (letting the subconscious mind perform maintenance). We take it easy exercise. When our eyes grow strained we close them.
But we seldom think about our digestive system's need to rest and recover. The way many people eat causes an almost continuous barrage of activity. Some people really do eat around the clock, even getting midnight snacks, and keep their digestive system working nonstop for decades.
After we eat, it takes 6-8 hours before the stomach and small intestine are finished digesting the meal, but if we do not go longer than 8 hours without a meal, we'll never experience a fasted state, and our digestive system will not rest.
The colon takes even longer to process food—around 24 hours for someone eating a whole foods diet, and more for someone eating the standard American diet.
This means that within the first 24 hours since your last meal, your stomach and small intestine have been off-duty for 16-18 hours.
Fasting for 36 hours (every other day) gives the digestive system an even deeper rest, benefiting not just the stomach and small intestine, but also the colon.
Theoretically, this rest allows the body to turn its energy elsewhere. The digestive process is a tremendous load, burning around 10% of the calories you take in each day to function from start to finish. When the body is no longer using energy to digest food, it has more energy for other processes. It's like stopping to sit after a long run. We soon feel more energized and able to keep running.
It has been said that during a fasted state the body will break down cancer tumors and the plaque on artery walls, and re-regulate functions like insulin secretion, as if the body is running a defragmentation program.
Fasting also helps regulate the digestive system, resting it so that when it's time to digest food again it does so more efficiently. This is vital for good health because we're then able to get more out of the food we eat, absorbing more vitamins and minerals, antioxidants, protein, etc.
I could go on, and even write a book on fasting—as many others have—especially on the weight-loss benefits, which I have not touched on. There's a lot of material to digest, but I think it's enough here to cover some of the key benefits of fasting.
An Overview of Intermittent Fasting An objective talk on intermittent fasting.
Mark's Daily Apple A comprehensive look at fasting, including many links to other resources.
And if you want a reason not to fast, I've got that, too: The Dangers of Intermittent Fasting. The stance of organizations like the American Cancer Society seem not to be too enthusiastic about accepting fasting as a treatment, providing ample warning against it, while admitting that in animal trials fasting has shown benefits.
To be honest, and I'm being subjective here, I've never seen a valid argument against fasting. Most arguments fall apart in light of research and peoples' personal experiences.
Like anything, it's necessary to research it and try it in moderation before committing to it as a lifestyle. Fasting may not feel good, it may cause unsavory side-effects. It's not a panacea for everyone.
Think for yourself, and listen to your body.