I've recently embarked on a 21 day water only fast. I've done fasts before, the longest of which was about 5 days before I got completely bored and needed to eat something.
Intermittent fasting has become quite a popular weight loss method. It started with the 5:2 diet, 5 days a week you eat normally but on the other 2 days, you consume only 500 calories.
From that, fasting diets like 16:8 and 20:4 came about, the largest number is the time you go without eating and then you have a smaller "eating window" if you like to consume your calories.
Week long fasts or longer are more extreme. You consume 0 calories. I've been tweeting about these fasts and naturally, people have been somewhat concerned but generally supportive. Elsewhere, I've had comments about "starvation mode" and "it's not healthy" but is there any truth to that?
This isn't something I've woken up one morning and decided to try. I've been fasting on and off for a couple of years now, before embarking on this very long 21 day fast I did a lot of research.
There's a lot of myths and misinformation about "starvation mode". The idea is that if you don't eat, your body will hold onto and store all the fat it can. When you think about it, this doesn't make much sense.
The body stores fat so that it can use it for energy during a time of famine, during a time where you're not consuming anything. What would be the point of storing fat only to not use it when you've not eaten anything? The body is smart, it's designed for doing exactly that. Storing fat to burn at a later time.
Starvation mode is a very real thing, but studies have shown fasting doesn't trigger it. Low calorie diets however, do. Reducing daily calorific intake during a conventional diet has shown to slow the bodies metabolism to match the intake. If you're suddenly eating less, your body slows down to avoid "over spending". Interestingly, complete restriction of calories increases the metabolic rate, the main theory here is that the increased metabolic rate allows you to burn fat more sufficiently and keeps your energy levels up. Think back to 'hunter and gatherer' days, if you hadn't eaten for a while, more energy would be more beneficial to help you find food, it wouldn't make sense for your body to shut down entirely within days of not eating.
"It's not healthy"
This is a fair comment. We're surrounded by food adverts, companies trying to sell you their products. "Breakfast is the most important meal of the day" is an idea literally born in a marketing room to sell breakfast cereals, there's no real "science" supporting that phrase, but it's become so ingrained into us and we hear it so often that nobody questions it.
Breakfast. "Break" "fast". Everybody fasts, when you go to bed your body is fasting, breakfast is simply breaking that fast.
Studies show fasting to completely reverse diseases like type 2 diabetes, reduce the risk of alzheimer's (or completely prevent it, in some mouse studies). It's also shown to quite significantly reduce the risk of cancer/improve prognosis of cancer sufferers (most studies have again been on mice, but there are some human trials on going)
I'm fasting for a number of reasons;
- To improve general health and wellbeing
- To lose a few extra lbs I've put on this year
- Mental clarity
Humans have been fasting since the dawn of time. Muslims fast for a month every single year. The world record without food is 384 days and there were 0 adverse side effects. Fasting improves insulin resistance, it improves blood sugar levels, it improves heart rate, it improves cholesterol. There are so many positive benefits to fasting.
I'm currently on the third day without food. Hunger has been a slight issue, I felt light headed for a short while. On longer fasts it's important to supplement sodium, potassium and magnesium especially, your body needs those electrolytes. Always do extensive research before attempting something like this, it's certainly not something you should just "wing it".