Fasting vs Calorie Restriction
To eat less or less often?
Most people who have every tried to lose weight will be familiar with the idea of cutting 500 calories from their diet. The logic being that 1 lb of fat is roughly equivalent to 3500 calories and therefore if you just cut 500 calories from your diet per day then after a week you will have a deficit of 3500 and a drop of 1 lb of fat…
Yes, lots of people know this and many have tried it… and normally with the same result. Weight loss for a few week followed by stagnation, frustration and weight gain.
Some of you may also have heard about fasting. It comes in many flavours, Intermittent fasting, Prolonged Fasting, Liquid Fasting, Fat Fasting, Dry Fasting… Each has their advantages and all can cause fear… the fear of hunger. But are some of the more simple fasts really something to fear at all and are their any advantages to fasting over calories restrictions?
In this piece i am going to show you the difference between a simple fasting structure and calorie restrictions. We are going to look at how they both work.
Lets imaging you are a person who eats 2000 calories a day. Your body weight has not changed in any significant way for 6 months and you eat 6 meals a day comprising of breakfast, lunch, diner and three small snacks. You decide they want to lose some weight and cut your calories to 1500 per day. So what happens inside your body?
If your body weight has not changed recently and you were eating 2000 calories a day then we know that your metabolic rate is set to burn 2000 calories a day, (Or is it? More on this a little later.), because if it was set lower than that you would still be gaining weight and if it was set higher than that then your weight would be going down. But it is doing neither; it is stable so we know it’s running at 2000 calories per day.
So you reduce your calories by 500 per day and hey presto, the body is burning 2000 but only taking in 1500 and your body weight starts to go down. But here is the catch… Each and every time you eat the the body goes into storage mode. It spends several hours digesting your food, and then shuttling it around through your blood stream to your muscles, brain, organs, skeleton and fat cells. While this process is going on your body can’t release stored fat for fuel to burn because the hormones that cause the release of stored fuel and the ones that deal with the storage of the food cannot co-exist. It would be like trying to turn a light on and off at the same time. It can’t be done. And when it comes to burning stored fat or storing new food your body has an automatic default setting… Store. This is because having food floating around in your blood is extremely dangerous so no matter what else is going on, when food comes in the body goes into storage mode until it is all stored away safely, (I explored why this occurs in “Why we burn Carbs first”).
So, because you are eating 6 meals a day your ability to access more than the 1500 calories you are eating becomes very difficult. Only when you are sleeping is your body getting access to some of that stored fat. With a shortage of available food your body starts to lower it’s metabolic rate. So while at the start of your calorie restricted diet you were still burning 2000 calories a day after a few weeks your metabolic rate will begin to drop to your new 1500 calorie limit and all weight loss stops.
Worse still, this means that when you get fed up with the lack of results and return to eating as you did before, your metabolism is still at the 1500 stage. so the weight goes back on fast.
Feasting and Fasting.
So now lets look at what happens if you were to do exactly the same 1500 calorie restriction, but you were to do it with some intermittent fasting. Lets say you cut those 6 meals to 2 and you had them within a 4 to 6 hour window each day. You still get exactly the same amount of calories but you get to enjoy them in two large sittings rather than 6 small ones
Firstly what you will notice is that you will feel a lot more satisfied after the larger meals. But the benefits go way way beyond that. Because your body is only in storage mode for a few hours a day it has access to all the body fat your body has to offer nearly all day long. Fat is released from storage and you body up regulates the hormones it needs to make use of this fuel. The body does not feel starved for energy because even the fat stores on a lean person are vast. This means the body can happily keep its metabolic rate at 2000 calories per day. The results is a much more even, steady and long lasting weight loss. Fasting also has the benefits of being muscle sparing so you won’t be losing precious fat burning muscle either.
Of course if you cut your calories low for to long no matter what you are doing, eventually your metabolic rate will lower but with fasting it wont happen anyway near as fast. And what’s more, with fasting you probably won’t need to cut your calories at all.
In truth you could easily keep your calories at 2000 right form the start and still see fat loss. The reason, is that once you turn of all those storage switches then you open up access to your full metabolic potential. By eating 6 times a day you had been tamping your metabolic rate down, so with just the two meals a day you have allowed your body to use more, burn more and store less. It’s like you have suddenly taken your foot off the break. So, your metabolic rate which had been held back at 2000 and now jumps to 2300 per day. So now you are burning more fat and your in a calorie restriction that you didn’t even know about.
I spend a lot of time helping people lose weight and get in shape and not everyone is ready to jump into the complicated world of calculating macros. For most, the first question i ask them is how many times a day they eat, including all snacks and any tea of coffee that includes milk. I then ask them if they can eat exactly the same amount of food but with less meals. Sometimes this means them eating all their snakes with their main meals reducing the amount of time they eat from 6 to 8 times a day to 2 to 3. And when they do, they usually see an immediate drop in weight without ever even looking at carbs, fats and proteins.
The human body does not count calories, it responds to chemical signals. What signals are you sending your body?
A quick word of warning. if you have low blood pressure or very low blood sugar levels then fasting may not be for you. If unsure seek professional guidance before starting a fasting protocol.