50,000 years ago our ancestors did not eat three times a day. Studies indicated that they had an omnivorous diet , such as pigs and bears, getting nutrients from the available sources both animals and vegetables. Basically, they ate everything they had at hand .

In fact, it is likely that our ancestors frequently were on an empty stomach several days before they could sink their teeth into something . The human body is more than prepared, because at the least chance it tends to store fat . These reserves allow anyone to survive for weeks without eating, of course, as long as they drink water.

In fact, fasting is present in one form or another in many religions, from the Muslim Ramadan , in which fasting from sunrise to sunset, to fasting before the Eucharist in Catholicism. Always with the idea of ​​»cleaning» the body.

Stop eating along with a detox periodically can be a great idea. It is important to make a prior consultation in order to check the state of the body -always with a professional nutritionist – to avoid any problem and ensuring to know what kind of foods are beneficial for us, as well as to learn the proper food intake and to mix the nutrients in the right way for each person to prevent diseases.

Types of intermittent fasting


The idea is not to stop eating for a week , although there is people who do it, because these prolonged fasts are counterproductive: they cause a loss of muscle mass and slow down your metabolism, leaving you worse than at you start point. This type of fasting is called intermittent due to the alternating periods of fasting and eating.

Alternating days

It consists of fasting for 24 hours and eating as much as you like for 24 hours. These are the studies that have been carried out more often using mice and with many positive results for their weight, fat mass, and longevity. But when doing it with people, it was verified that they lost fat, but at the cost of being very hungry  which makes it little feasible.

Feeding restricted by time

This method is applied every day: fasting for 16 hours (including night) approximately and eating as much as you want using an 8-hour window.

How intermittent fasting works


Most diets are based on caloric restriction: instead of eating 1,800 kcal per day, you eat 1,200, 30% less. This results in a fast weight loss, water, muscle mass, and some fat. The diets that work are those that do not compromise the loss of muscle.

Intermittent fasting also means reducing calories, but not to the day, but to the week . If your daily diet is 1,800 kcal and you stop eating two days, at the end of the week you have reduced your weekly intake by 30%. However, what is the difference?

The difference is in the body’s ability to adapt itself. After a week of starving on a hypocaloric diet your basal metabolism will fall. That means that your body spends less , even less than the reduced diet you’re already eating. The researchers call this phenomenon known as «adaptive thermogenesis», but you will surely find it as «metabolic damage». It is the reason why hypocaloric diets do not work .

The advantage of intermittent fasting is that there is a reduction in calories, but there is no adaptation, because you are only fasting for 24 hours at most. Before your metabolism goes down, you eat again and go back up.

In addition, intermittent fasting increases your metabolism by up to 14% and instead of losing muscle you will keep it .

Effects of intermittent fasting


There are several studies that have analyzed the effects of intermittent fasting on the human body in some of its modalities. Even more research is needed, but the results are very promising.

Intermittent fasting lowers blood insulin levels, especially after 16 hours of fasting, which makes it easier to burn fat and increase growth hormone levels , which makes muscles grow, improves the immune system and regenerates joints

Short-term fasting stimulates autophagy in the brain, a process by which neurons remove their damaged components, protecting themselves from neurodegenerative diseases .

It is a fact that restricting the amount of food prolongs life in tests with worms and rats, which can live twice as long. Intermittent fasting seems to work the same way, but without going through a sad life of constant hunger. By restricting the intake, sirtuins are activated, proteins that regulate inflammation and aging , protect cells from oxidation and prevent the proliferation of cancer cells.

Intermittent fasting seems to improve insulin sensitivity, lowering glucose levels and therefore could be used to prevent the onset of type 2 diabetes .

It has also been shown to be effective in reducing inflammation and oxidative stress , two of the factors that cause cardiovascular diseases.

On top of that, intermittent fasting lowers LDL cholesterol , increases HDL cholesterol, lowers blood pressure and triglycerides.


How to do it?


Testing the effects of intermittent fasting on oneself can not be simpler but keep these indications in mind:

The most comfortable way is by doing the most of the fasting time at night. For example, you can eat your lunch as you normally do but then you will not eat anymore in the day. The next day, skip breakfast and eat for the first time at noon.

During the fast, drink water like there’s no tomorrow. You can also drink tea, coffee and in general, any liquid without calories. No, you can’t add honey to your tea.

Start with one day of fasting per week. If you get used successfully then  you can do it in two non-consecutive days. For instance: Tuesday and Friday.

Make sure that the day you start fasting is a day off from your exercise program. The next day, exercise just before the first meal.

Avoid prolonged exercise while fasting. If you exercise strength or intervals, take a small portion of proteins, a shake or tablets of amino acids containing leucine , which will avoid burning muscle mass.

How can you fail with intermittent fasting?


If you use it to give you binge-eating : after the first day of fasting there are those who take revenge and throw themselves to eat junk food for the rest of the days. In a study with mice, after fasting they were put up, canceling out all the beneficial effects . You can fall into the same. Intermittent fasting only works if there is a reduction in total energy, and that is achieved by eating normally the rest of the time: proteins, vegetables and controlling carbohydrates. It’s not an excuse to eat donuts by the dozen.

If you do not do sports : the restriction of calories will always produce a loss of muscle, and the best way to avoid it is the exercise of strength . It’s a bad idea to do long runs at a jog, because your body can start to burn muscle instead of fat. It is best to do a short session of high-intensity exercises or weights just before the first meal after fasting.

If it is not intermittent : the proposals of the miracle diets, such as the maple syrup, the onion and others are a way to go hungry, lose muscle, lower your metabolism and your weight bounces as soon as you eat again.

If you wish to know more about our nutrition and detox programmes  do not hesitate to visit our BioClinica Marbella website.


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