What Is Intermittent Fasting?
Intermittent Fasting (IF) is the act of going without food or other caloric intake for a period of time, typically 15-24 hours. During this time, your body is unable to derive energy from incoming food and must instead turn to its stored energy (carbohydrates in the form of glycogen, amino acids, and fats) to maintain bodily functions. This is important as it gives the body time to focus on repair and immunity away from the highly energy intensive digestive process and forces the body to use all of its available energy pathways.
How Do I Do It?
There are two basic versions of Intermittent Fasting. While you'll derive the benefits of fasting from either method, a little experimentation will show you immediately which is your preferred method.
The Alternate Day fast, whereby you fast for 24 hours, then eat for 24 hours is the first method. You can implement this form of IF in various ways. For example, you can eat until 6pm, then not eat again until the next day at 6pm. By doing so, you still get to eat everyday, but you have a 24-hour period for the body to relax and not deal with digestion.
The second version approaches the day's meals from a hunter-gatherer perspective and could most appropriately be called a Compressed Window IF. By fitting all of the day's calories into a 4-6 hour window, rather than spreading them over the course of 14-16 hours as most people do, the day is freed up for other activities. The hunter-gatherer perspective, a lens through which all human endeavors should be viewed given our evolutionary history, is that during the day, our ancestors would have been out and about, finding food, with most eating occurring in the evening.
Let's Cut To The Chase. What Are The Benefits?
By experimenting with both versions, I have found that the Compressed Window version of IF works best for me. I go through my day at work, then head home and eat a large salad with plenty of colorful vegetables, nuts, eggs, sardines, and olive oil. After allowing some time for digestion, I then move into my evening meal, which is typically some sort of meat with prodigious quantities of vegetables and sometimes a sweet potato. Basically, I subsist on two large meals per day.
Of course, the question in your mind now is probably something along the lines of, "Yeah, but everybody knows you have to eat 5 times per day to have a lean body. What do you look like?" I easily maintain my weight of 185 pounds and 10% bodyfat at a caloric intake of over 3000 calories per day this way. It is so effortless that for the last few years, I've only gotten leaner and stronger while doing IF.
I have found numerous benefits of fasting [out], and many others report similar ones:
* Improved mental clarity during the fast
* Improved workout performance during the fast
* Lower body fat percentage at the same bodyweight (i.e., more muscle mass)
* No worry about food during the day - I can get up, run out the door to work, work all day, then go home to eat. I don't have to be concerned with fitting in lunch and food is no longer the focal point of my day.
* No food-induced crashes during the day - I'm on top of my game all day. Even eating low-carb Paleo on a normal eating schedule left me more lethargic than this
* Better in-tune with my body - you learn to distinguish psychological hunger (i.e., it's noon and I should eat) from real hunger. When I get truly hungry, I break the fast and eat, even if it's outside my "window"
* More energy - You'd think I'd experience fatigue with no food intake, but I can't quit moving and having an urge to go run around the block during a fast
* Food tastes better - it's amazing how much better a well-cooked meal tastes when you haven't eaten all day
* I sleep better
A big fear for most people is that without eating they won't have the energy to go about their day. On the contrary, my body has learned how to tap into its fat reserves to provide more than ample energy during a fast. In fact, I find my workout performances are significantly better when working out fasted. Other people report the very same thing too! It's as if the body is meant to work this way.
As I said above, I'm far more energetic during my fasts than after a meal, regardless of the meal composition. Studies show that markers of inflammation decrease, hormones associated with disease protection increase, and healing is improved when fasting. It appears that the brain is protected from toxic stressors, the body increases its cancer protection, and aging is slowed from fasting. All of these benefits from just going without food for a few hours a week!
Ok, I'm Intrigued. But How Do I Start?
The easy answer to that question is "slowly". Obviously you can't just stop eating every other day and expect your body to react with approval. I found it easiest to slowly increase the length of my fast. First, I just started skipping breakfast and increasing the size of my evening meal to compensate for the calories. I broke my fast every day at lunch time for a few weeks, then started moving lunch closer to dinner, about an hour every week. Eventually, my first meal was moved to the evenings when I was home from work.
I started an experiment with a 24-hour fast, eating from 6pm to 6pm, then fasting until the following 6pm. I found that many of the benefits of fasting, such as the lack of food-induced crashes were missing. On the days that I woke up and ate breakfast, even a low-carb breakfast of eggs and spinach left me a bit less perky than simply not eating. That's why I say that you'll have to figure out which version of IF works best for you.
One Final Word of Advice
One very important thing about fasting is that, while you can get away with less optimal food choices than you can on a normal diet, food quality makes fasting much, much easier. You can actually gain weight while fasting if you are loading up on sugary processed foods during your eating periods rather than focusing on quality meats, vegetables, nuts, seeds, and fruits.
In the end, there is no "best" way. The best way is what fits easily into your lifestyle and allows you to focus on living, not when your next meal is going to come. I urge everyone to try this approach to eating.
Ready To Try It?
If you're ready to give Intermittent Fasting a shot to improve your health, check out the excellent eBook "Eat Stop Eat". In this book, you'll learn the hows and whys of Intermittent Fasting and see exactly how to incorporate it into your lifestyle.
