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  • Writer's pictureJaime Hernandez

Intermittent Fasting How It Works

Intermittent Fasting

How It Works

A body of research is emerging on the health benefits of intermittent fasting. There are many ways to fast, but no matter which method a person chooses, the breakdown of what’s happening in the body is generally the same.

Most healthy humans have about a thirty to forty day supply of body fat and we’ve actually evolved to do intermittent fasting because food was not always plentiful. In our culture today, we have constant access to food and our digestive systems rarely get a break from working full-time. I learned a great deal about fasting from the movie “The Science of Fasting” which is currently available on Netflix.

A fasting treatment can last anywhere between two and thirty days depending on what that individual’s health professional deems necessary and what is safe for that person. The treatment normally includes drinking plenty of water and caring for the body in other ways such as light exercise, massage, hydrotherapy, and/or infrared therapy for the duration of the fast. Some people do a modified version which includes intaking some calories but only about 25% of their average daily amount.

The first three days are very difficult because your body is being depleted of glucose stores and your body starts to go into acidosis. The body also gets low on vitamin C, D,E and other components of the metabolism. The acidosis phase can be hard to get through because you can feel weakness, nausea, and headaches. The body is being forced to live off of its reserves and is under stress, creating a mental challenge as well as a physical one. By the third day, there’s a lot of elimination and detoxification of the body and that is why most people don't feel well. As the body cleanses itself though most people start to feel better.

When under the guidance of your doctor you can get your urine tested and it will tell you when your body is changing its primary fuel source. When your body is going into acidosis and it raises the level of acid in your blood. The doctor in the documentary I mentioned calls it “the crisis" and warns that the disease will actually get worse before it starts to get better. She says that only last from twenty-four to thirty-six hours and then it passes. "The crisis "is a profound event because the body has to learn to feed on itself as it’s not getting fuel from an outside source.

How does the body feed on itself?

There are three primary sources of fuel that our bodies use: glucose, protein, and fat. The essential fuel is glucose, which the body absolutely needs in order for the brain to function. After twenty-four hours of fasting, the glucose supply is nearly depleted and our bodies need to produce glucose by taking apart our muscles. However, it will also take from our fat reserves to make another substitute for glucose, the fasting fuel is known as ketone bodies. It is the ketone bodies (manufactured by the liver) that will be the primary fuel for the brain.

After "the crisis" the body has found a new equilibrium and people can begin activities to help them cope, like colonics, sauna, hot baths, massage, and light exercise to stimulate all of the elimination organs: kidneys, intestine, liver, skin, and lungs. It’s also normal during a fast to have food cravings at first, but once you get past a certain point you’ll start feeling euphoric and have a clear mind.

It’s important after fasting for long periods of time to start eating again in a way that is gentle for your body, starting with light foods such as soup and veggies. Of course, before starting something like this I recommend consulting your doctor. Fasting done correctly can have great benefits to your health, and if you have any questions regarding your health journey please feel free to contact me at

Thank you for your time and energy. Be well.

Jaime Hernandez



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