Here’s something new that I want to share with you. Intermittent fasting is an absolutely fascinating idea that may sound crazy to you, but it’s actually really incredible. I wanted to share this article when I first started intermittent fasting but alas, I waited several weeks to make sure I get comfortable with it and enjoy it. And yes, I love it, so here goes. This article is also an exercise in critical thinking to help dispel nutrition myths.

What is Intermittent Fasting?

Click to expand When you hear the word fasting, you probably think of people who are eating nothing but lemon juice and water for a week. But that’s not what Intermittent Fasting is. For example, one of the styles which I enjoy the most is called the 16/8 protocol: 16/8 means… You don’t eat for 16 hours. (This is the fasting phase.)

Then you eat all the calories you normally would eat in the other 8 hours. Here’s how I see it: When you wake up in the morning, you’re already half way through the fasting phase because you haven’t ate anything for the past 8 hours. Then you simply skip breakfast and don’t eat anything until lunch time. So instead of eating between morning and evening, you simply eat between just the afternoon and bedtime. This gets the body used to burning fat for energy rather than carbs because there are literally less carbs to breakdown. As a result, people like me are breaking through plateaus and experiencing significant drops in body fat when combining it with a healthy diet and exercise. Here’s the same example, but using numbers: If the last time you ate was at 8pm and you go to bed, then wake up at 8am, that means you’re 12 hours into the fasting phase and just have 4 more to go. You just have to refrain from eating until 12:00pm (Noon) to complete the 16 hour cycle. Then afterwards, you could eat your usual two or three meals in the next 8 hours (until 8pm, with this example). The trick is to not eat more calories than you normally would within those 8 hours, which is pretty easy. It turns out that it’s much more satisfying/satiating to eat 1,500 calories in 8 hours rather than 12. There are many IF variations: 24 hour fast for one day of the week and normal, healthy eating for the rest (called Eat Stop Eat diet)

Lean Gains (incorporates 16/8 IF, calorie cycling and macro cycling.)

5:2 which means you eat normally for 5 days of the week but eat less than 500cal for each of the other two.

Alternate Day Fasting (ADF) means fast for 24 hours every other day. Is one better than the other? The 16/8 is not a true fast for 16 hours because you eat food and it takes hours for it to digest. This is what Martin Berkhan, creator of LeanGains, incorporates because there is no muscle loss involved with this. In fact, that’s the whole point of LG (to gain massive muscle strength and massive fat loss) down to the lowest body fat levels possible. The 24 hour fast is the most studied and has been shown to have extremely good oxidative effects. It’s assumed that a 16 hour fast will reap a good amount of benefits without having to be as “extreme” as a 24 hour fast. I talk about this in detail below.

This sounds bizarre, why did you start this program?

Click to expand I had been counting calories for three solid months using MyFitnessPal. I went from 180lbs to 168lbs in the first two months, which was great. All I did was make sure I ate 1,600 calories a day (a deficit of nearly 1,000 calories) and kept exercising like usual. I would often easily stay within the deficit during the weekdays and would cut myself some slack on the weekends. I tremendously enjoyed the benefits of losing the equivalent of a sack of potatoes off my body. But for the third month, I didn’t lose any more weight. I kept eating a healthy diet that averaged out to 1,600 calories a day and exercising plentifully. And despite all the exercise and calorie counting, I was stuck at ~168lbs. I know that I was losing fat and gaining muscle very slowly though, but here’s what was driving me crazy: It seemed like no matter how big of a breakfast I ate, I would be faced with a crazy amount of hunger after. Hunger that I didn’t have to deal with before. And even worse, the heartier and larger my breakfast was, the more extreme and ravenous my hunger would be afterwards. Apparently this is not unheard and common for people that get in a lower body fat percentage. It was very clear that I had reached some sort of dreaded plateau and that I had to change something. While I don’t really care about how much I numerically weighed and I know 168lbs is already a great number, I wanted to keep losing some weight to reap even more benefits. So that’s when I was doing some research and discovered IF.

MYTH: But I’ve always heard that to keep your metabolism up you should eat 6-7 tiny meals instead of 2-3 big ones throughout the day. Won’t that increase your metabolic rate? Like constantly providing wood to keep the fire burning.

Click to expand If you add little pieces of wood to a fire, it will intensify the fire. If you add a GIANT log to a fire (akin to eating a large meal), it will practically extinguish the fire. That’d be great if your stomach was a fireplace but I’m sorry, it’s not. It’s not literally burning food by fire and you most certainly aren’t eating wood. Listen, I’m not saying eating small meals throughout the day doesn’t “work.” It works because it controls peoples hunger so they don’t go ape-shit come lunch or dinner time. But there’s absolutely nothing magical about it and it definitely doesn’t “rev up” your metabolism. Ultimately, what matters most is reducing your total calories regardless of the number of meals or snacks. Studies have shown there is absolutely no weight loss difference between dieters who eat their calories in three meals daily versus six. (WebMD source) Now, I’m not saying people don’t lose weight by splitting their large meals up into smaller ones. I’ve definitely done it, but it has nothing to do with splitting the meals up. It has to do with trying to feel satiated all day so theoretically you don’t eat a large meal.

What pisses me off the most is this fireplace/wood analogy. Nothing could be further from the truth physiologically.

Click to expand This metabolic-fire-analogy is a very common myth perpetuated by infomercials. Here’s the physiology behind how your body actually loses fat: Your body stores a 24 hour supply of carbs in your liver and muscles in the form of glycogen. Glycogen is simply a chain of glucose molecules snapped together. If you exercise vigorously, the glycogen supply will be exhausted within just a few hours. If your body runs low on glycogen, it switches over to breaking down fat for fuel because it has no other choice. There are no other carbs in your body for your body to access. Even though we eat carbs all the time, only 1% of our body weight is made of carbs. The body tries to use carbs immediately as they are ingested. If you eat an excess amount of carbs, fat oxidation (fat burning) goes down because carbs are the preferred source of energy for your body because fat takes a much longer time to break down. If you constantly keep eating food every 2 hours, then your glycogen supply (carb supply) is constantly being filled and your body is using the carbs from the food for energy. Your body has no reason to burn the fat that’s on your body if it’s constantly being fueled by food. But if you go hungry for many hours and you allow your blood sugar to fall, your body will release triglycerides from fat cells, break them down into free fatty acids and use them for energy. This breakdown of fat is known as lipolysis. So in other words, the only way to burn fat (lipolysis) is to simply go hungry once in a while because it’s only when you run low on carbs is when your body will resort to lipolysis. (Note: This is why people lose fat on the low-carb/keto/atkins diets!) Now, when you’re fasting and just standing around or doing low-strenuous cardio like walking, your body is mostly burning fat for energy because your body can take its sweet time to break it down for energy. If you exercise vigorously, your body taps heavily into your glycogen stores because carbs provide a much faster source of energy and only carbs can be processed anaerobically. Fat and protein can’t be broken down anaerobically (without the presence of oxygen). Only sugar can be broken down anaerobically. When the glycogen-reserves run out, and you keep trying to vigorously exercise, the expression commonly used is, you’ve “hit the wall” because it feels like you can’t move anymore. This is why marathon run­ners say run­ning the last 6 miles is harder than the first 20. Your body has no choice but to switch to burning fats when the glycogen runs out and since fat can’t be burned anaerobically and takes more effort for your body to burn, all of a sudden you barely have enough energy left to exercise. Here’s the point: I used to eat immediately the moment I felt the slightest anticipation of incoming hunger. Now, I know it’s totally okay to be hungry once in a while. You’re not supposed to eat 6 meals a day like as if you’ll die if you don’t. Biologically (and evolutionarily speaking), your body has no trouble keeping your body regulated without food for several hours. Side Note: This “fire” idea probably came about when scientists discovered the thermic effect of food (TEF). For example, protein is often said to contain about 4 calories per gram but in actuality, when your body is done processing it, it turns out to be more like 3.2 calories per gram. So your body has expended some energy trying to use that energy. That’s the thermic effect of food. The infomercial-marketers took this idea and ran with it to mean other things.

MYTH: But wait, doesn’t fasting cause your metabolism to drop cause your body thinks it’s starving and it goes into “survival mode” or “starvation mode”?

Click to expand Absolutely not. It takes several days of fasting for your metabolism to drop like that. Here’s a quote from Martin Berkhan in a guest post on the Fitness Black Book: “Metabolic rate does not slow down during short-term fasting. It actually increases slightly. That’s probably the complete opposite from what you’ve heard, but this is an undisputed fact. It takes more than three days without food before metabolic rate is negatively affected via down-regulation of thyroid activity. That skipping breakfast or missing a meal affects metabolic rate, a myth still propagated in the fitness and health community, is ludicrous.“

Sorry but your body doesn’t think you’re starving and it’s not going into “survival mode” just because you haven’t ate breakfast and lunch yet. Check this out: The average 150-lb. man has about 1,800 calories worth of glycogen stored in their muscles and liver available for energy for normal body processes and exercise. Fit people can store even more glycogen in their muscles. If you want numbers, a trained muscle can hold approximately 32 g of glycogen per 3.5 oz of muscle tissue, while an untrained muscle only holds 13 g of glycogen. A 175-lb athlete can hold up to 4,800 calories worth of energy in the form of glycogen. This is why an athlete has so much more strength on tap and endurance. It takes 2-3 days of fasting for the glycogen reserve to be completely exhausted because when you’re sitting around or doing low-intensity cardio (like walking), your body is breaking down a mix that is predominantly fat with some carbs. (Fats take a long time to break down for energy so it’s usually only used when the heart isn’t beating too fast, otherwise it switches to carbs for a faster energy source). Martin Berkhan, creator of LeanGains, chooses 16/8 because he says that maximizes fat oxidation while minimizing protein breakdown. Or in other words, the body doesn’t start looking at protein for energy until after the 16 hour mark.

So when does your metabolism drop from fasting and your body starts breaking down muscle? It isn’t until your body needs to start breaking down muscle mass to use the protein that we consider this to be starvation and your body truly goes into starvation mode. The earliest evidence for a lowered metabolic rate in response to fasting stated that it occurred after 60 hours and there was an -8% drop in resting metabolic rate. Other studies show metabolic rate is not impacted until 72-96 hours have passed. [Here’s more info that dispells this myth.] tl;dr: Short intervals of fasting does not slow your metabolism. In fact if you wanted to know the truth, studies show that intermittent fasting actually speeds up your metabolism. Slowing of the metabolism only happens after extended periods of fasting, at least several days, which is not what we’re trying to do or care to do.

So what are the benefits to IF? Turns out to be one of the most impressive “diets” I’ve ever come across in terms of anti-aging benefits.