“Eat breakfast like a king, lunch like a prince, and dinner like a pauper.” – Adelle Davis
I have the utmost respect for Adelle and her historical contribution to nutritional science. The good news is with the advances in modern science there appears to be many ways to skin this cat.
Nearly every single fitness website you stumble upon now has some sort of article that is a primer or 101 guide to Intermittent Fasting. This particular dieting protocol has exploded in popularity in the last 5 years and even the NY Times recently did a piece observing its rise.
Conventional teachings held as gospel around meal timing and the dreaded starvation mode are now being directly challenged by Intermittent Fasting and for hackers like us trying to find the path of least resistance, this is great news.
Intermittent Fasting is one of the most powerful dieting protocols in existence that allows you to sustain a caloric deficit over a long period of time.
What is Intermittent Fasting?
Intermittent Fasting is a dieting protocol that splits your 24 hour day up into a fasting window and a feasting (eating) window. Your fasting window has to be longer than your feasting window.
How does it work?
Very simply. After you eat a meal, your body is in a “fed state” and spends the next several hours breaking down that food you just ate. Since the energy is immediately available in your bloodstream from what you ate, it doesn’t tap into your fat storage cells. RESULT: No change in stored fat.
8-10 hours after your last meal, your body finally breaks down all the food you ate. You are now officially in a “fasted state” and your body has no food (energy) in its blood stream. So the only source of energy it can tap are your fat cells. RESULT: Stored Fat level drops.
Here is a more technical breakdown (from Wikipedia)
Insulin & Glucagon: Think of these as the opposite ends of a see-saw. When one goes up, the other goes down. They are opposing forces (hormones) that keep blood glucose (the see-saw plank) at a stable level. Insulin is produced to lower the level of glucose in the bloodstream.
Glucagon is produced to raise the level of glucose in the bloodstream. High blood-glucose levels (immediately after eating) stimulate the release of insulin and low blood-glucose level (during fasting) stimulates the release of glucagon (which causes the liver to convert stored glycogen into glucose).
When you eat food your body (pancreas) produces insulin to break down blood sugar. The more sensitive your body is to insulin the more efficiently you will break down foods you just ate which means less will be stored as fat.
Conversely the less sensitive your body is to insulin, the less efficiently you break down foods and the more gets stored as fat. This is why type 2 diabetics whose body cannot produce insulin or who are extremely insulin resistant have to take an insulin shot before they eat.
Your first meal after a fast + heavy lift will be the most efficiently burned as the food ingested will directly be used to replenish glycogen storage and for muscle recovery with very little stored as fat. This is also why I advocate having your cheat/treat after a heavy workout. It just makes sense mechanically.
The long and the short of it is that during the fasting window your body will directly burn body fat as the only source of energy since there is no food in your body.
What are the benefits?
- If you haven’t tried IF before you can get an immediate kicker in your leaning out process by simply adding this in. Your body will be “shocked” so to speak.
- You don’t have to stress out about meal prep. Long gone are the days of stressing out about preparing 6 small meals a day.
- When you eat, you can eat BIG. Like I said, this is a dieting protocol that allows you to maintain a calorie restriction over a long time. I’ve been doing it for 5 years and I don’t plan to stop.
- Studies have shown that after fasting Growth Hormone (which is essential in losing fat and gaining muscle) increases. GH also increases after a workout (and after sleeping). Finally GH counteracts cortisol the stress hormone that is linked to belly fat storage.
- The practice of IF can help with appetite control. It does for me. Ghrelin the enzyme that your stomach lining produces to stimulate your appetite. Fasting stabilizes this enzyme.
What are the drawbacks?
- There aren’t a lot to be honest. BUT the effects of IF in women are definitely different. Here is a great article that explains it pretty well.
- The initial transition will be difficult. Your body will take some time to adjust to shifting your eating around. But like most things, the human body is very adaptable.
- What about muscle loss? That is another lie developed by the multi-billion dollar supplement industry. We actually don’t need protein every 2-3 hours like they say we do.
- Won’t I pass out if I don’t eat? You won’t for a while. Isn’t that bad for my blood sugar levels? I thought that’s why I have to have 6 small meals a day? You thought wrong.
What different types of IF protocols are there?
- Leangains (16/8): Popularized by Martin Berkhan who is one of the authorities on the subject and an early advocate of IF (since 2006). Much of my knowledge on the subject comes from his extensive research and I highly recommend that you visit Martin’s blog (www.leangains.com) for more self-education.
- Eat Stop Eat (5:2): Brad Pilon is the second “Godfather” of the IF movement and regardless of if you use his method or not I recommend you reading his research based book for personal learning. His approach is basically to do 1-2 full 24 hour fasts every week and the rest of the time during the week you eat normally. The 24 hour period is manageable if you fast after a big dinner and then don’t eat until dinner the next day. I use this sometimes around the holidays or when I know I have a big night out coming up.
- The Warrior Diet (20/4): By Ori Hofmekler. 20 hour fast followed by a 4 hour feeding window. Based on Roman/Spartan warriors who were out to battle all day, the main meal is dinner after fighting all day. This is a much looser IF model as it “allows” a small meal in the morning and/or fruit snacking throughout the day as needed. I personally have not read the book.
- Alternate day fasting (ADF), involves a 24-hour fast followed by a 24-hour non-fasting period. This is sometimes referred to as every other day fasting or every other day feeding. Personally not appealing to me and I cannot see this being easy to maintain over a long period of time.
Ok, I’m interested. How do I get started today?
I thought you’d never ask. Here are the guidelines:
- Every day will consist of a Fasting window of 16 hours and a Feeding window of 8 hours. This is often referred to as “16/8” in fitness parlance.
- The easiest way to fast is by skipping breakfast which would make your fasting window from after dinner until lunch the next day (8pm – 12pm) and your feeding window from lunch until dinner time. (12pm – 8pm)
- During the fasting window you will not eat any calories. No breakfast!? Are you crazy!? Yes this will take some getting used to. The first few days are painful and your stomach will be growling. Black coffee (with a splash of skim milk if you need) and sparkling water help blunt appetite. Or you can try a piece of sugar free gum as well. Just make sure not to go over around 10 calories so your body remains in the fasted state. The great thing is that you will notice changes to your body (belly) almost immediately when you start IF.
- Try to stay busy during the fasting window. I am most productive in the mornings during my fast. Train your mind not to think about food but instead focus on work.
- From 12pm – 8pm is your feeding window. There is some flexibility around how you choose to take in your calories during this time. I recommend eating a large lunch and a large dinner and NOT snacking as this usually leads to over eating. But if you want to spread out a bunch of small snacks over the 8 hours that’s fine too. Just make sure you stay within your calorie limit for the day.
- The reason I recommend 2 large meals is twofold: 1) it is crucial that you get a big meal in after a demanding workout so this depends on when you schedule your workout 2) psychologically it is much easier to end your day and go to sleep on a full stomach than an empty stomach.
That’s it. I’ve been practicing Intermittent Fasting (IF) since 2011 and have found such freedom in eating. I was a skeptic at first having been very much of the belief that without 6 meals a day my metabolism would die.
It was what every fitness book, magazine, website, and professional told me so I thought it was the truth. My life was completely centered on my meals and I drove my wife nuts with the meal prep.…oh no the dreaded starvation mode!
With IF, I can maintain my caloric restrictions (remember, just cause you are on IF doesn’t mean you can go nuts and eat whatever you want…you still need to stick within your caloric budget) and eat big at the same time. Long gone are the days of stressing out about meal prep and making 6 small meals a day.
Caveat: Please check with your doctor first before you jump into IF if you have issues with blood sugar regulation, diabetes, hypoglycemia etc.