Intermittent Fasting for Beginners

Intermittent fasting, besides being an excellent way to lose weight in a healthy way, is a powerful tool in the fight against many diseases. It also promotes healthy aging and longevity because it activates the production of growth hormone. Fasting has an anti-inflammatory effect preventing chronic diseases such as cardiovascular, autoimmune, and oncological diseases.

Intermittent Fasting for Beginners 

To do intermittent fasting it is important to follow some basic recommendations such as: 

• Do not eat solid foods during the fasting period and liquids with calories, such as fruit juice or coffee with sugar;
• Give priority to eating healthy foods in the intervals between fasting; 
• Drinking plenty of water and unsweetened teas throughout the day.

During the fast you can consume some beverages, such as coffee, water, and natural teas without sweeteners. When resuming your diet, it is important to prioritize healthy and low-carbohydrate foods, such as pumpkin or spinach, whole grains, legumes, lean proteins, and healthy fats like avocado, for example.

Practicing fasting regularly increases the burning of body fat, helping not only in weight loss, but also in strengthening the immune system, since it accelerates the cell renewal of the whole body, including the defense cells. It also improves physical and mental disposition, and prevents premature aging and diabetes.

How to start intermittent fasting 

There are different ways to do intermittent fasting, and the most well-known methods are:

16:8 method

In the 16:8 method, you fast for 16 hours without eating, with an 8-hour "window" for eating.

To follow this method you should stop eating at 8:00 PM, for example, and resume eating at 12:00 AM the next day.

In the 8-hour "window" it is recommended to eat seasonal fruits and fresh vegetables; whole grains, such as brown rice or whole wheat noodles; lean proteins, such as fish and eggs; and legumes, such as beans and chickpeas.

During all this time it is important to maintain good hydration, drinking at least 1.5 liters of water a day, and drinking coffee and natural teas without sweeteners or sugar is also allowed.

5:2 method

You should eat your meals normally for 5 days of the week, and go on a calorie-restricted diet for the other 2 days of the week, which should be alternated with at least one day in between.

To follow this method, on Monday, Wednesday, Friday, Saturday, and Sunday, for example, you can eat a balanced diet with no calorie restrictions. On Tuesday and Thursday you should keep your diet balanced, but reduced to only 20% or 25% of your daily caloric needs.

This means that a person who normally consumes 2000 calories a day, on the 2 alternate days of intermittent fasting, should consume only 400 or 500 calories a day, for example.

24-hour or alternate day method
 

This method can be a bit more challenging, as it consists of alternating days of complete fasting. That is, you must go without eating food for 24 hours straight, resuming a balanced diet the next day.

In this method, you must fast Monday, Wednesday, Friday, and Sunday, for example. On the other days of the week, food should be eaten at normal times, giving priority to a balanced diet.

On fasting days, drinking water and natural teas without sugar or sweetener is allowed and recommended to maintain hydration and help control hunger.

20:4 method

This method, known as the "warrior diet," may not be ideal for those just starting out, as it is the most restricted of all the intermittent fasting types. The period you must fast is 20 hours, and the "window" for eating is only 4 hours.

For example, you must stop eating at 8:00 PM and only resume eating at 4:00 PM the next day. Because it is very restricted, this method is usually better tolerated by people who are already used to doing other forms of fasting.

Because protein, carbohydrate, vitamin and mineral intake can be very low in this method, it is important that it be done under the supervision of a nutritionist to avoid nutrient deficiency.

What is the best method to start? 

To start intermittent fasting, the easiest method may be the 16:8, as it is the type of fasting where you go only a few hours without eating.

To get used to the method, you can start fasting for 6 hours during the day and gradually increase each day until you reach 16 hours, for example.

Another option that can make this start easier is to add sleeping hours to the total fasting time, sleeping 8 hours, for example, and only needing to fast another 4 to 6 hours until the next meal.

Common questions when starting
 

1. Is intermittent fasting safe?

Yes, intermittent fasting is a safe tool for most people who wish to lose weight, improve metabolism, and strengthen the immune system.

2. Do you feel very hungry during intermittent fasting?

Some people may feel a little hungry at the beginning of intermittent fasting. To decrease the feeling of hunger it is suggested that you start intermittent fasting once a week, for 12 hours or less, and gradually increase the hours of fasting.

Another suggestion is, during the period when you can eat, have meals with low glycemic index foods, as this helps the body to slowly release sugar in the blood, helping to control hunger during fasting. Dehydration can generate signals in the body that confuse hunger with thirst. Therefore, drinking at least 1.5 liters of water throughout the day can also help control hunger.

3. Who cannot do intermittent fasting?

Intermittent fasting is not indicated when you have any disease, such as anemia, high blood pressure, diabetes, low blood pressure, or kidney failure. It is also not indicated for people with a history of anorexia, binge eating, bulimia, or who are underweight.

It is always advisable to consult with a doctor or nutritionist before starting and during intermittent fasting.

4. Can I train during intermittent fasting? 

It is recommended to train normally during the fasting periods, because the physical and mental disposition will be increased, contributing to the increase in metabolism and fat burning during physical activity.

However, on the more restricted fasting days, such as 24-hour, 20:4, or 5:2, it is recommended that you engage in lighter physical activity, such as walking and/or yoga.

If symptoms such as weakness, dizziness, or malaise appear during workouts, it is important to stop the activity until you feel better, and if symptoms persist, it is important to see a doctor.

Going through an evaluation with a nutritionist and a physical activity professional can also be interesting to evaluate the need to adjust the intermittent fasting or the level of physical activity.

5. What can I drink during intermittent fasting?

During intermittent fasting it is recommended to drink plenty of water and natural teas without sweeteners or sugar. These beverages are essential to maintain hydration, besides helping to control hunger, especially for the beginners of the method. Unsweetened coffee is also allowed during the fasting period.

6. Does intermittent fasting cause muscle loss?

Intermittent fasting doesn't cause the loss of muscle, because the method stimulates the increase of GH (growth hormone) levels in the blood. With this, besides the method facilitating the burning of fat in the body, helping in weight loss, it also preserves the muscle mass.

In addition, intermittent fasting can still contribute to the gain of muscle mass, because during the method there is an improvement in mood and physical endurance.

7. For how long can I do intermittent fasting?

Most studies evaluating intermittent fasting have been done for 6 months, but it is safe to do it for longer.

However, before starting intermittent fasting, it is important to consult a nutritionist who will evaluate the best method according to the goal you want to achieve and your tolerance.

8. Does intermittent fasting decrease the metabolism?

Intermittent fasting does not decrease the metabolism, except in cases of fasting done for more than 3 consecutive days. However, in controlled intermittent fasting and for up to 3 days, the low intake of calories reduces the levels of glucose and insulin in the blood, forcing the body to use the body's fat cells, and this even promotes an increase in metabolism.

9. Can I do intermittent fasting every day?

For people who are looking for general health improvement, mood enhancement, and strengthening of the immune system, intermittent fasting can be done daily.

For weight loss purposes, intermittent fasting should be done up to 3 times a week. This is because fasting for more than 3 days a week causes the body to adapt to the calorie restriction in the diet, slowing down the metabolism and slowing down weight loss.

10. Is there an ideal menu for intermittent fasting? 

There is no ideal menu for intermittent fasting. However, in the intervals of fasting it is recommended to maintain a balanced diet with fresh fruits and vegetables, legumes, and lean proteins, which are important to maintain the benefits achieved with the method.

11. Can children and pregnant women do intermittent fasting?

Children should not do intermittent fasting, because they are at a stage when the body needs more nutrients for formation and development. Intermittent fasting is also not recommended for pregnant and breastfeeding women, because these are times when the baby needs high amounts of calories and nutrients, which are provided through the mother's food.

Sources
www.hsph.harvard.edu