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What happens during intermittent fasting hour by hour?

Updated: Mar 8

Regardless, if you are new to intermittent fasting or experienced at fasting, it is good to understand the amazing changes your body will go through during the hours of intermittent fasting, but first, I want to talk about why we are suited to do intermittent fasting.

Why we are suited to do intermittent fasting

Feasting and fasting date back to the days of our hunter-gatherer ancestors who lived 2,5 million years ago until 10,000 years ago. Think about that for a minute; that is the majority of our history, and as a result, feasting and fasting are stamped into our DNA. This is great because when you start intermittent fasting you will adapt quite quickly and overcome whatever hurdles or worries you might have had at the start. You will notice changes for the better relatively fast and wonder why you didn't start intermittent fasting ages ago.

Feasting and fasting are stamped into our DNA
Feasting and fasting

We have evolved to live a fasting lifestyle. We have NOT evolved to eat three meals and two snacks a day. Since mankind started this constant eating lifestyle, we have become seriously overweight and sick with chronic inflammation, diabetes, Alzheimer’s, heart disease, allergies, depression, cancer, and, of course, obesity.

Fasting is the oldest healing strategy and possibly the most powerful, and it’s a money saver. Think of all that money you will save from not taking expensive medication and not eating and snacking all day. It’s a win-win.

What happens during intermittent fasting hour by hour?

So what is actually happening in the body when you take a food break? The times may vary a bit depending on if you are already on a ketogenic diet or if you are experienced at fasting. In both cases, it will be quicker to get into ketosis and autophagy and your detox symptoms will be less than if you are starting out new.

As we get older, the cells in the body can’t repair themselves anymore, and we age. How about if there was an easy and inexpensive way to change this? Fasting for a few days has amazing anti-aging effects and can result in having a longer and healthier life. During fasting, you will trigger the body to start repairing, recycling, and getting rid of your most unhealthy dying cells (apoptosis). You will also regenerate new cells in the brain.

6-12 hours of fasting: Blood sugar and insulin levels are lowering. The liver starts to break down glycogen stored in the liver and the muscles for fuel.

12-24 hours of fasting:

After the glycogen stores have been depleted, this signals your body to begin reaching for stored body fat for energy instead, and fat burning starts. This is when you enter a state of ketosis. Around 18-24 hours of fasting and autophagy kicks in. Autophagy is mighty, and it is a process in which the body starts repairing and recycling on a cellular level. This will most likely generate detoxification symptoms, like headache, fatigue, and irritability, and you probably feel hunger and cravings at this stage. As you shift into a deeper state of ketosis the hunger and cravings will disappear.

Feasting and fasting
Intermittent fasting hour by hour

24-36 hours of fasting:

There is a surge in Growth hormones (GH) to preserve muscle mass, burn fat, boost the immune system, and promote bone density. Did you know that we don't produce growth hormones after the age of 30, and some people are injecting GH for anti-aging and healing. It's expensive and can have serious side effects. I would do fasting for free any day instead of injecting myself with lab-developed GH. Gut healing stem cells are increasing in the gut. I wrote a blog about how you can reset your gut and heal Leaky gut, SIBO, and Candida. Read my blog about healing the gut here.

As a result of healing your gut, your brain health will start to improve, you will experience mental clarity, and that annoying brain fog will lift.

36-48 hours:

At this stage you should be over the worst detox symptoms, unless you were living a very unhealthy lifestyle, then it might take a bit longer. Hormone receptors will start resetting and anxiety levels come down. Your liver starts healing and cholesterol levels come down. The anti-aging effects are revving up and it's magic for your skin and wrinkles.

72 hours:

3 days of fasting and your stem cell account has increased further. Your immune system will have had a near-complete rejuvenation, new cells are created and replacing old ones. (Dr Valter Longi study). The same study also showed that cancer patients who fasted throughout chemotherapy treatment kept their immune systems strong. If you have an auto-immune condition, especially Rheumatoid arthritis, you will start noticing improvements.

Intermittent fasting is safe for most but.....

Doing longer fasts over 24 hours requires caution. Do not run before you can walk. It's always best to start off slow, and if you are not sure where to start, get yourself a certified fasting coach who will guide and support you every step of the way.

Remember water fasting is not for everyone. Do not water fast if you are seriously ill (without consulting your medical doctor), if you have or have had an eating disorder, if you are underweight, or If you are pregnant or a nursing mother.

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