In the documentary of his journey "Eat, Fast, and Live Longer", a British journalist Michael Mosley explains how to live longer thanks to fasting which allows to improve health. Before he left, he was borderline diabetic and had high cholesterol to the point that his doctor wanted to prescribe medication.

Concerned about this diagnosis, Michael Mosley set out to find alternative ways to solve his health problems.

Throughout his journey across the United States, he will meet healthy seniors and longevity experts who will explain the secrets of their success.

Our body is punctuated by cycles. One of them is the one based on the alternation "Meals - Fasting".

Fasting has been proven to be beneficial for many health problems including cardiovascular disease, reduced risk of cancer, vitality, regeneration and longevity.

It is true that severe caloric restriction promotes weight loss and longevity in animal models, but this kind of "starvation diet" is not a very attractive strategy for most people.

Recent research has shown that rather than practicing permanent caloric restriction, it is better to alternate periods of fasting with a few days during which you feast.

These eating habits are similar to those of our ancestors who could not obtain food on a daily basis. They alternated periods of feasting and dieting.

This alternation demonstrates a number of biochemical advantages. In short, by changing your feeding schedule, you can radically alter his physiology.

In short, eating too often and too rich, seems to be a morbid process.

It is probably not a coincidence that fasting is part of certain age-old spiritual practices aimed at purifying the body and the mind, which modern science has confirmed.

Here are some good reasons to practice fasting:

• It normalizes insulin, leptin and ghrelin (hunger hormone) secretions while improving the energy efficiency of mitochondria. Sugar is a source of energy for the body, but it promotes insulin resistance and promotes chronic, inflammatory diseases and cancers. Fasting has a direct impact on this insulin sensitivity and on sugar cravings.
• It will help your body reuse fat as its main fuel instead of sugar.
• It promotes the production of human growth hormone (HGH), which maintains physical fitness and slows the aging process. This hormone increases fat burning, which is certainly why fasting is so effective for weight loss.
• It lowers blood triglycerides and balances other biological markers.
• By decreasing the accumulation of cellular free radicals, it reduces stress and oxidative damage to cellular proteins, lipids and nucleic acids associated with aging and disease.
• It has also been identified as a powerful preventive factor and even a treatment for dementia. This is because ketones (a by-product of fat burning), which are the brain's most prized fuel, become more abundant.
• It stimulates the production of neurotrophic proteins which in turn activate brain stem cells that will be converted into new neurons.
• It increases the levels of other chemicals that support neuronal and brain health. Thus the practice of youth protects against Alzheimer's disease and Parkinson's.

What does "intermittent" fasting mean in practice?

Dr. Mosley, a firm believer in the benefits of intermittent fasting, wrote a book about it: "The Fast Diet: Lose Weight, Stay Healthy and Live Longer with the Simple Secret of Intermittent Fasting".

After trying out several fasting patterns during his documentary, Dr. Mosley proposes a fasting schedule in his book.

He finally suggests eating normally for 5 days a week and reducing the amount of food and calories to 600 for men and about 500 for women on the other 2 days. This should be accompanied by plenty of water and tea. Dr. Mosley claims to have lost 9 ½ pounds in two months with this intermittent fasting practice.

Another variation used quite frequently is to alternate a day of fasting (including sleep) with a day of normal eating. This covers a long period of 32 to 36 hours since you normally go to bed on the day you ate and do not eat again until the morning of the following day. At first, the hardest part for some people seems to be going to bed on an empty stomach on fasting days.

Research shows that alternating these normal eating days with caloric restriction days works just as well for weight loss as periods of complete youth.

A third possibility of intermittent fasting may be to reduce food intake daily for 8-hour periods. This last possibility seems to be the easiest to respect, because it can be set up progressively, starting with 6-hour diet periods and reaching 9 to 10 hours on certain days when you are less hungry.

If you do this, the dieting ranges will gradually lengthen as your insulin and leptin sensitivity normalize, as will any problems with weight, blood pressure, high cholesterol, diabetes or snacking and cravings.

What to eat outside of fasting periods?

Some doctors say that when you practice this method of intermittent fasting, you can eat whatever you want in any quantity and of any quality.

Dr. Mosley disagrees with this statement. In fact, the adoption of this lifestyle is generally the result of a health and ecological awareness, and an ethic with the intention of purifying one's body, staying in better health as long as possible or improving it if it is deficient. This seems quite contradictory to the current junk food situation.

Outside of fasting periods, the ideal is to respect the main principles of a healthy diet. This means: reducing the intake of starchy, sugary and refined foods rich in carbohydrates, avoiding processed foods, replacing "bad" fats with healthy fatty acids such as coconut oil, olive oil, flaxseed oil, hempseed oil or clarified butter. Replace animal proteins with eggs, macadamia nuts (particularly rich in good fats and low in protein) or avocados and greatly reduce dairy products.

It is recommended to eat good dried fruits and a lot of fruits and vegetables more especially raw or lightly steamed.

While complete fasting should be avoided in certain cases and sometimes even medically supervised, intermittent fasting can be practiced by everyone. Caution should be exercised in cases of diabetes or hypoglycemia, and for people suffering from chronic stress (adrenal exhaustion) or cortisol dysregulation. Pregnant or breastfeeding women should also avoid fasting, as the milk must be rich in nutrients to meet the needs of the baby.