Fasting is becoming more and more fashionable, whether for detoxify either lose weight or help treat some disease. We hear about intermittent fasting, other people fast with juices, others fast only one day a week… there are many different versions of fasting, so here I explain the basics to understand a little more about each one.

He fast It is the voluntary abstinence from the consumption of solid foods and stimulants (such as caffeine, tobacco and alcohol) for a certain period of time to obtain different benefits as intended. In addition, fasting has been used for many years and continues to be used in many religions, since it is believed that fasting helps people to purify themselves, renew themselves and reach a spiritual level or get closer to the divine.

Types of fasting

There are different types of fasting and each one affects the body differently. Here I explain the characteristics of the most common ones.

1. Long fast: This fast is carried out by completely eliminating calories from the diet and consuming only liquids such as natural water or infusions (teas) for weeks or months, as necessary.
2. Intermittent fasting:This type of pattern involves consuming food and then fasting for periods of 12 hours or more. Most people who do intermittent fasting usually set specific times in which they consume food and fast the rest of the time. For example, eating from 8 am to 8 pm to fast for 12 hours.
3. Alternate day fasting: In English this method is called fast and feast and involves days of complete fasting and days of free food consumption.
4. Periodic fasting: It is usually a fast of 1 day a week.
5. Juice fast: It is a food restriction, rather than a fast where only fresh fruit and vegetable juices are consumed. This is usually done with the goal of obtaining the benefits of nutrients from vegetables without the body having to do extreme digestion to absorb these nutrients, allowing the body to focus on repairing tissues and nourishing itself quickly.

How long could you fast without damaging your health?

This completely depends on each person, since we all have different energy and nutrient reserves. When we stop eating and our body needs energyit can obtain it from different tissues in our body. The main source will be fats, since the body makes these fat reserves for times when there is no food. Although there are also other places from which we can obtain energy (calories) such as muscle glycogen and liver and muscle proteins.

On average, a healthy 70 kg man has enough energy to fast for approximately 98 days. More than you thought right? Of course, this is just an estimate and each person is different. A person with obesity could surely fast for longer due to the amount of fat accumulated in the body.

Another consideration is micronutrients such as vitamins and minerals, it is important that if you are going to do long fasts you have medical supervision to avoid health problems.

Side effects and contraindications

Fasting can have beneficial health effects, but it is not for everyone. The following diseases or conditions are contraindicated:

• Cachexia
• Anorexia nervosa or another eating disorder
• Uncontrolled hyperthyroidism
• Dementia and advanced cerebrovascular insufficiency
• Advanced kidney or liver failure
• Pregnancy and lactation

Depending on the fast you decide to do, there are several side effects that people can have and are usually normal in most cases:

• Headaches or migraines
• Mild hypoglycemia
• Changes in electrolyte levels
• muscle cramps
• Acute back pain
• fluid retention
• Changes in sleep patterns

In order to evaluate whether the symptoms you have are normal or not, medical supervision is needed; especially in the case of some diseases where it is necessary adjust medicationsIn this case, it is highly recommended to have medical supervision throughout the entire process, before and after.

How is a long fast carried out?

Due to so many types of fasting and lack of research What is there about the effects of prolonged fasting to treat different diseases, before starting a fast it is crucial to go to a health professional who is an expert on the subject to avoid complications.

Germany is a country that has seen the benefits of fasting to help improve different conditions, which is why fasting is used as a public health strategy following certain standards and indications published in a review carried out by the University of Berlin where a group of experts established different guidelines for subjecting patients to fasting.

Before fasting

Before starting a fast it is important that people leave preparing physically and mentally. As recommended in the book Fasting and Eating for Health from Dr. Joel Fuhrman, it is important that before and after fasting you clean your diet (completely avoid processed foods) and reduce foods of animal origin, to begin preparing the body for this purification process.

There are studies, such as in the German guides for fasting as therapy that I mentioned previously, where it is also recommended to make a calorie restriction the day before, prepare schedules and activities to have enough time to rest, have some type of enema and perform physical activity at a mild to normal intensity.

during fasting

During fasting it is important to be aware of why you are fasting and be aware of physiological changes that occur. Normally, the consumption of dietary supplements is not necessary, but during prolonged fasts, symptoms must be monitored to avoid deficiencies.

When finished

Breaking the fast is as important as the fast itself. It is important to do slowly and gradually and it will begin with the introduction of vegetables – a single type and avoiding combining foods at the beginning – preferably organic, local and completely natural. This is a great time to identify how the body responds to different foods and simple food combinations to avoid if discomfort occurs.

Finally, it is important to maintain a healthy eating rich in plant-based, whole and organic foods so that the effects of fasting last as long as possible.

Remember that There are no “miracle” treatments.Rather, there are effective processes and treatments as long as they are accompanied by changes in habits that in the long run will help you have a fuller life.

If you are thinking about doing a long fast, consult with a health professional to make sure you are a good candidate and that you will do it appropriately.