Is Intermittent Fasting For You?

What is intermittent fasting? If you listen to certain people it's a silver bullet for losing fat and keeping muscle.

Really it's just eating within a restricted time window. Sometimes it's incorrectly described as a diet. It's not a diet. A diet is made up of the foods you eat. Intermittent fasting is just a schedule when you eat.

You could consume nothing but candy bars and bacon but if you only ate them between noon and 8p.m., technically you'd be intermittent fasting. I wouldn't recommend that diet but feel free to try it and email me how it goes for you.

So we now know intermittent fasting is eating only during a certain time, but what exactly is that window?

It depends.

Probably the most common way people do intermittent fasting is the way popularized by Martin Berkhan. Here you fast for 16 hours and have an eating window of 8 hours. At first that might seem extreme, but remember that you're asleep for about half of those 16 hours.

A simple way to implement this is to skip breakfast and push your first meal back until lunch. You don't eat or drink anything with calories until your window starts. Water is your friend here. So are black coffee or tea, provided you don't add in anything with calories. Water helps you feel full. The coffee and tea contain caffeine which suppresses appetite.

A huge help is to keep busy. Keep your mind off the food you're not eating by rolling through your to-do list. Ever notice when you're totally engrossed in getting stuff done time flies by and you don't even think about eating? Yeah, do that.

Why skip breakfast rather than dinner? Technically, it shouldn't mean a difference to your body. But for social reasons, it's usually much easier to skip breakfast than to stop eating at 3:00 or 4:00 in the afternoon.

It's taken as common knowledge that breakfast is "the most important meal of the day". It's not just untrue, that originated as a marketing ploy to get people to buy more cereal. It's safe to say it worked.

What's magical about eating from say, noon to 8:00pm? Nothing, really. But compressing all your eating into a narrower time makes it more difficult to overeat, which makes it easier to get (or stay) leaner over time.

There's also nothing magical about the time frame. It's not as if the benefits evaporate if your window was 11:45am to 8:15pm. You want to stay as close as you can to that 8-hour eating window, but you don't turn into a pumpkin if it's not exactly 8 hours. You do want to avoid that 8-hour window creeping to 10 hours, 12 hours, 16 hours.

If you want to try the 16/8 approach it may be helpful to ease into it. If you normally eat breakfast, push it back by an hour. Then another hour, and so on until you're not eating until lunchtime. After a week or two, your body will adjust and you won't have those hunger pangs in the morning.

Also, as long as you adhere to the 16/8 window, it doesn't really matter if your window is noon-8pm or 1pm-9pm or whatever.

What does still matter is food quality. Eating in a smaller window means you can eat larger, more satisfying meals. However to get the best results, you want to stick to higher quality food.

Another way to do intermittent fasting is the 5/2 approach. For this, you eat as you normally would for 5 days. On the 2 other days, you restrict your eating to about 500-600 calories per day. It's best that those days aren't consecutive.

How does this work? It's just a different kind of eating window. Instead of a daily window like 16/8, you're using a weekly approach. Limiting your intake on two days will bring down your weekly average consumption.

For example, say your daily intake is 2500 calories. 2500x7 = 17,500 calories per week.

Change that to 2500x5 days + 600x2 days and you get = 13,700 calories per week. You've "saved" 3,800 calories by fasting twice a week. It's math, not magic.

A third option is Eat-Stop-Eat, made popular by Brad Pilon. Here you take 1-2 days per week and fast completely. That's right, you go a full 24 hours without eating, once or twice a week. You can have coffee, tea, water (flat or sparkling), as long as there are no calories. The other days you eat normally.

You don't have to jump right to a 24-hour fast. You can start with 16-18 hours and ease up from there.

The Warrior Diet is another way to go. This is where you eat a small amount of fruit and vegetables during the day and have a huge meal at night. You essentially eat very little during the day and have a feast within a 4-hour window in the evening.

If your mind isn't swirling with all the possibilities yet, I'll give you one more. There's Alternate Day fasting. Basically every other day you limit your intake to about 500 calories. This is kind of a beefed up version of calorie cycling. Calorie cycling is when you eat slightly more calories on days you do weight training and slightly fewer calories on days you don't. But, limiting yourself to 500 calories 3 days a week is going to be really challenging.

You're an adult, so you do what you want. I probably wouldn't recommend Alternate Day fasting.

The underlying principle is the same for all intermittent fasting, you limit your intake according to time. Other approaches have you directly limit the amount of food per day. Intermittent fasting is predicated on the idea that by shrinking the window you'll automatically also shrink the amount of food.

The amount of food (a.k.a. calorie intake) is the primary driver of whether you'll lose weight, gain weight, or maintain your weight. The quality of the foods you eat is the primary driver of whether you'll lose, gain, or maintain your health. A compressed eating window doesn't mean you have a license to eat garbage and expect a good outcome.

I should say here that it's possible to bulk using intermittent fasting. It's just a little more difficult because it would mean eating at a calorie surplus (more food) within a restricted timeframe.

How do these approaches affect training? It might be more difficult to train in a fasted state at first, but your body will soon adapt and you'll get used to it. You won't lose your strength or muscle.

No matter which eating schedule you choose, there are benefits to intermittent fasting. It's an easy way to indirectly limit calorie intake. If you enjoy larger meals, this may be a strategy that works well for you. Fasting gives your digestive tract a break. You'll also learn your hunger cues better. A lot of times we'll mistake thirst for hunger. Sometimes we even think we're hungry when we're just bored or anxious.

Finally, intermittent fasting is a tool, an option, not a directive. It may not fit with your lifestyle. If you have eating disorders in particular, it may not be appropriate for you. As you can see, if you choose to do intermittent fasting there are several ways to do it. It may take some tinkering to figure out which one suits you best.