If you have been hanging around keto groups for any amount of time, you will have come across the term intermittent fasting, or IF as it is refereed to. Or IF’s bigger, tougher sister OMAD which stands for one meal a day.
What Is Intermittent Fasting?
Intermittent fasting is an eating pattern where you cycle between periods of eating and fasting. It does not say anything about which foods to eat, but rather when you should eat them.
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I recommend that you combine intermittent fasting with the ketogenic diet for best results.
You already “fast” every day, while you sleep. Intermittent fasting can be as simple as extending that fast a little longer by skipping breakfast, eating your first meal at noon and your last meal at 7-8 pm.
Then you’re technically fasting for 16 hours every day, and restricting your eating to an 8-hour eating window. This is the most popular form of intermittent fasting, known as the 16/8 method. You can also do the 18/6 which is eating lunch at 12pm and your dinner finished by 6pm, or any thing that works for you.
Intermittent fasting is actually fairly easy to do. Many people report feeling better and having more energy during a fast, it does take a bit of getting used to, and to make it easier on yourself, wait until you are keto/fat adapted before attempting fasting.
Hunger is usually not that big of an issue, although it can be a problem in the beginning, while your body is getting used to not eating for extended periods of time.
Why would you do an intermittent fast?
If you think about it, humans have actually been fasting for thousands of years. Sometimes it was done out of necessity, when there simply wasn’t any food available.
Various religions, including Islam, Christianity and Buddhism, mandate some form of fasting. Humans and other animals also often instinctively fast when sick.
Clearly, there is nothing “unnatural” about fasting, and our bodies are very well equipped to handle extended periods of not eating. The problem is we struggle with it mentally. We have been trained to eat so often during a day.
All sorts of processes in the body change when we don’t eat for a while, in order to allow our bodies to thrive during a period of famine. It has to do with hormones, genes and important cellular repair processes.
When you fast, you will get significant reductions in blood sugar and insulin levels, as well as a drastic increase in human growth hormone. These metabolic health benefits can improve various different risk factors and health markers. This can help protect you against diseases, including heart disease, type 2 diabetes, cancer, Alzheimer’s disease and others.
Growth hormone is known to increase the availability and utility of fats for fuel. It also helps to preserve muscle mass and bone density. One of the most potent stimuli to growth hormone secretion is fasting. Over a five-day fasting period growth hormone secretion more than doubled. The net physiologic effect is to maintain muscle and bone tissue mass over the fasting period.
Intermittent fasting can be an effective “life hack” that makes your life simpler, while improving your health at the same time. The fewer meals you need to plan for, the simpler your life will be.
Types of Intermittent Fasting that work well with the ketogenic diet
There are a variety of types of intermittent fasting, you can simply chose what works best for you.
- The 16/8 Method: Fast for 16 hours each day, for example by only eating between noon and 8pm or the 18/6 version along the same lines.
- Eat-Stop-Eat: Once or twice a week, don’t eat anything from dinner one day, until dinner the next day (a 24 hour fast).
- The 5:2 Diet: During 2 days of the week, eat only about 500–600 calories.
- The OMAD where you eat just one big meal each day as a long term solution.
There are many other variations.
Doesn’t intermittent fasting slow down your metabolism?
Not really, no. Long term low fat, high carb, low calorie diets will slow your metabolism down like you wouldn’t believe. In this state your insulin levels are high and fluctuating, and you are HUNGRY. This is the diet that they used on the biggest loser, and as studies have shown, these people drastically reduce their metabolic rate (1).
Short-Term Fasts Boost Metabolism by up to 14%
Many people believe that skipping meals will cause your body to adapt by lowering its metabolic rate to save energy.
However, studies have shown that fasting for short periods can actually increase your metabolism, not slow it down. One study in 11 healthy men found that a 3-day fast actually increased their metabolism by an impressive 14% (4).
Regular fasting, in addition to lowering insulin levels, has also been shown to improve insulin sensitivity significantly. This is the missing link in the weight loss puzzle. Most diets reduce highly insulin-secreting foods, but do not address the insulin resistance issue.
Weight is initially lost, but insulin resistance keeps insulin levels and Body Set Weight high. Fasting is an efficient method of reducing insulin resistance.
Doesn’t fasting burn your muscle?
Well, now that is just silly. Let’s imagine that we are living in Paleolithic times. During the summer of plenty, we eat lots of food and store some of that as fat on our body. Now it is winter, and there is nothing to eat. What do you suppose our body does. Should we start burning our precious muscle while preserving our stored food (fat)? Doesn’t that sound pretty idiotic?
It’s as if you store firewood for a wood-burning oven. You pack lots of firewood away in your storage unit. In fact, you have so much, it is spilling out all over your house and you don’t even have enough room for all the wood you’ve stored. But when the time comes to start up the oven, you immediately chop up your sofa and throw that into the oven. Pretty stupid right? Why would we assume our body is also so stupid?
The logical thing to do is to start burning the stored wood. In the case of the body, we start to burn the stored food (fat stores) instead of burning precious muscle.
As long as you stick to healthy foods, restricting your eating window and fasting from time to time can have some very impressive health benefits.
It is an effective way to lose fat and improve metabolic health, while simplifying your life at the same time.