Updated: Apr 28, 2022
Do you see fasting as starvation?
Many people see it that way, but fortunately, it isn’t the same thing.
According to Britannica.com, fasting is defined as, the “Abstinence from food or drink or both for health, ritualistic, religious, or ethical purposes”.
Fasting has at least been practiced therapeutically since the 5th century BCE.
Maybe you know about the Greek physician Hippocrates. He had revolutionary ideas and was among the first who supported and recommended fasting. He along with other physicians believed that in some sick states, the fasted- was superior to the fed-state.
Back in time, even cavemen “fasted”, although it was more out of necessity than out of pure choice. Obviously, the food wasn’t plentiful back then. So, they sometimes hunted for days for their next meal.
The Fasting Options Are Plentiful
The fasting options are vast and there isn’t one “right” way to do it. Still, fasting is often a reduction in either meals or the avoidance of food for days. The most practiced type is intermittent fasting. This typically includes a fast between 14-18 hours per day. Hence, this often means skipping 1 meal/day.
Benefits Of Fasting
Speed Up Weight Loss by Fasting
Fasting is splendid for weight loss. This has for instance been shown in a 2015 study. During this study, the participants did alternate day fasting.  Alternate day fasting includes either a massive reduction in calories or no calories at all on 1 day. Then on day 2, you consume your normal number of calories.
Fasting May Slow Down Aging
Studies in mice show an increase in longevity. For instance, a study from the year 2000 showed how female mice who fasted 4 days in a row, every 2 weeks, lived longer than the control group. These mice lived about 33% longer, even though they were heavier than the control group.
Many other studies have shown benefits in many health indicators.  This is highly encouraging, yet it doesn’t mean that it necessarily will do the same in humans.
Improve Your Body Composition with Fasting
Human Growth Hormone (HGH) is important for muscle building and fat loss. Now, these outcomes are wanted by a vast majority of people. Fortunately, during fasting, the levels of HGH increase.  Thus, fasting seems beneficial for many individuals, all the way from a middle-aged mom to an elite athlete.
Fasting Helps Normalize Insulin Functioning
Is pre-diabetes or insulin sensitivity an issue of yours?
When you consume too many carbohydrates, your body may become insulin resistant. Over time this can lead to many chronic diseases including type-2 diabetes. To prevent this, your body must remain insulin sensitive.  A study from 2014 demonstrated how intermittent fasting reduced fasting insulin and insulin resistance.
Another study from 2017 was conducted on adults with type-2 diabetes. This study concluded that intermittent fasting improved their glucose levels.  Based on these studies, fasting may very well be an important tool in preventing type-2 diabetes. The 2017 study even suggests that it may help reverse the disease.
Normalize Your Hunger Levels with Fasting
The hunger hormone “ghrelin” is responsible for telling your body when it is hungry. Most people feel hungry throughout the day because of eating habits.  Usually, these signals only increase when you restrict your diet. However, fasting doesn’t do this. It helps normalize ghrelin levels. Consequently, your body might only send hunger signals when it needs food.
Promote Ketosis by Fasting
You probably already know that your body’s primary fuel source is carbohydrates. But what does your body do, when all your carbohydrate intake has been utilized as energy?
When your carbohydrate (glycogen) stores are empty, your body must find an alternative fuel source. The alternative source is ketone bodies (ketones). Thus, your body must enter a state of ketosis. It is very efficient at utilizing ketones for fuel. Because of that, you can survive weeks without any food. Other species can survive even longer. For instance, the king penguins can survive for over 5 months without food.
Can You Fast Too much?
Absolutely. You probably didn’t see this one coming.
The reason has to do with the starvation hormone glucagon. It opposes the action of insulin.  Glucagon is the driving force behind adaption to starvation.  It is produced by things like:
High protein animal diets
The hormone is the underlying fat loss mechanism of high protein animal diets and intermittent fasting. The activation of glucagon is not an issue per se. The problem is that you can create a hyper elevation of glucagon in the serum, which persists.
This constant elevation of the hormone drives insulin resistance over time. 
It’s easy to demonstrate. Research shows glucagon can readily induce insulin resistance in the liver.  Other studies show fasting glucagon levels increase 1 to 1 with insulin resistance. A study even showed how healthy men experienced impaired glucose tolerance and clearance after just 60 hours of fasting. 
Precautions For Some Individuals
Studies have not been performed on the very old and fragile, children, underweight individuals, and pregnant- and breastfeeding women. Consequently, it is possible that it may be harmful to fast if you belong to one of these groups. At least, it would be wise for you to discuss a fasting regimen with a physician.
Discover If the Advantages Outweigh the Risks
Fasting has lots of benefits. No question. Too much, however, can drive imbalances in serum glucagon, which can drive insulin resistance. This demonstrates the highest truth of health. Balance is essential. Imbalanced inputs, even from healthy things, can create imbalances in the body, which left unchecked, create disease.
From an ancestral standpoint, this also seems to make a lot of sense.  A low-carb high animal protein diet, AKA a Winter Diet, would facilitate insulin resistance and drive obesity. Then during the summer and fall, fruits and other carbohydrates are plentiful, allowing you to store fat and survive the winter.
How To Act on This Information
You may start by eating dinner a little earlier or eating breakfast a little later. Another way to get started is to simply eliminate all kinds of snacks. Both changes will make a big difference over time.
As your body becomes more efficient at using fat for fuel, you can choose to fast more. You might choose to fast for 16 hours a few times a week. Maybe you want to go for 1 24-hour fast combined with a few shorter fasts throughout the week. The possibilities are endless.
How To Have a Successful Fast
If you want to have a successful fast, you might want to keep a few principles in mind:
Figure out what your goal is
Decide what type of fast you want to do
Have an accountability partner
Stock the fridge with healthy foods
Give yourself a reward for completing a fast, especially a long one.
Punish yourself for not achieving your fasting goal
Fasting Can Become a Mental Challenge
Once you get to a certain number of hours, it might become more of a mental challenge than a physical one. This will be different for everyone. For some, it might happen after 20 hours of fasting. For others, it might occur after 2 days of fasting.
Are you ready for a mental fasting challenge?
As previously mentioned, there are many different types of fasting. Every single one can benefit you in one way or another. If you’re an athlete, it can help you. If you’re trying to lose weight, it can help you. If you want to live longer, it can be right for you. Even if you are a diabetic, it can help you out. It seems like no matter your goal, fasting might be beneficial, in one way or another.
Now, what is your health goal?
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 https://www.britannica.com/topic/fasting  https://draxe.com/nutrition/benefits-fasting/  https://pubmed.ncbi.nlm.nih.gov/26374764/  https://www.sciencedirect.com/science/article/abs/pii/S0047637400001093  https://pubmed.ncbi.nlm.nih.gov/?term=fasting+longevity  https://pubmed.ncbi.nlm.nih.gov/19240267/  https://www.dietdoctor.com/health/insulin-resistance  https://www.translationalres.com/article/S1931-5244(14)00200-X/fulltext  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5394735/  https://fastingplanet.com/when-do-hunger-pains-go-away-when-fasting/  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3946160/  https://en.wikipedia.org/wiki/Glucagon  https://link.springer.com/chapter/10.1007%2F978-3-642-69019-8_12  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6312800/  https://pubmed.ncbi.nlm.nih.gov/8923841/  https://pubmed.ncbi.nlm.nih.gov/1254728/  https://www.nationalgeographic.com/foodfeatures/evolution-of-diet/
A Question for IM Readers:
What is your preferred type of fasting?
Share your thoughts below!
ABOUT THE AUTHOR
Andreas is a Danish transhumanist, radical longevity advocate, market strategist, and writer. He graduated International Business Bachelor (IBB) from Niels Brock Copenhagen Business College in 2018 and has since put his business skills to a test. In early 2019, he began his first venture and has since worked with different personal brands, small firms, and various publications on various parts of the business. During this time, his biggest focus has been on business strategy, product development, and learning about the latest in longevity and emerging technologies.
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