Many popular diets promote the benefits of intermittent fasting. Fasting may have many health benefits. However, when breaking a fast, there are no particular rules about what to eat for the best effects.

In recent years, intermittent fasting, alongside other types of fasting, has gained popularity, thanks to diets such as the 5:2 diet.

Different approaches advise someone to either reduce their calories or eat nothing on certain days or overnight.

What someone eats when they break a fast is not as important, but some experts advise a Mediterranean diet.

This article looks at fasting and its potential benefits. It discusses what to eat after fasting and provides tips for both short fasts and longer fasts.

lighter foods such as cous cous salad, pictured here, are a good example of what to eat after fastingShare on Pinterest
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Fasting has become popular because many people believe it may improve health, longevity, and weight loss.

Throughout history, people have practiced fasting for spiritual, survival, or religious reasons.

Popular approaches to fasting for health reasons include alternate day fasting, overnight fasting, and time-restricted eating.

According to a 2015 review, evidence from animal studies suggests that intermittent fasting could have benefits for weight loss and chronic disease prevention. The authors suggest this may be due to the effects of fasting on circadian rhythms, gut microbiota, and metabolic regulation.

Other research indicates that health benefits may be due to metabolic switching, where fasting triggers the body to switch its source of energy from glucose to fats and ketones.

The production of ketones, or ketogenesis, may enhance the body’s resistance to oxidative stress and inflammation, with beneficial effects for health and aging.

Some popular fasting diets, such as the 5:2 diet, advise someone to eat a Mediterranean diet because of its health benefits.

However, the critical aspect of fasting is restricting energy intake from food on certain days or hours. This method encourages metabolic switching to fat and ketones.

When someone starts eating again, their glucose levels increase, and the body transitions towards using carbohydrates as fuel. Therefore, it is more important what someone does and does not eat when fasting and less significant what they eat when breaking a fast.

However, for weight loss, someone may choose to eat less refined carbohydrates when they break their fast, as research suggests these can contribute to obesity.

A short fast may involve fasting for 16 hours overnight or reducing calories to 500–600 for 2 days per week.

During these fasting periods, someone will either eat nothing or limit eating to a certain number of calories, depending on their approach.

Many nutrition experts recommend the Mediterranean diet for periods of low calorie fasting or regular eating days.

Some fasting diets allow people to consume vegetable broths or soups or vegetable juices, so long as they are within the number of calories the diet allows. People should always ensure they hydrate with sufficient water.

Individuals should also be aware that taking supplements, such as protein powders, gummy multivitamins, and branched-chain amino acids, may counteract the fasting effect.

Research suggests that combining exercise with intermittent fasting can result in improved mental and physical performance.

Some research shows positive effects of longer-term fasting, but this is in a medically supervised environment.

In a 2019 study, 1,422 participants fasted for 4–21 days for a total of 1 year. During the fasting periods, they consumed only water, juice, and vegetable soup totaling 200–250 daily calories.

There was a subjective improvement in 85% of cases of a major health issue. The authors suggest the fasting was safe, and the subjects tolerated it well, with few side effects. These reported side effects included:

After fasting, the study researchers gradually reintroduced food over 4 days. They gave the participants organic vegetarian food increasing from 800 to 1,600 calories per day.

However, it is important to note that the study involved supervision by medical professionals. People should not undertake longer fasts without first consulting their doctor, particularly if they:

  • have a health condition
  • are taking medication
  • are pregnant
  • are breastfeeding

Fasting can have beneficial effects on health due to calorie restriction and metabolic switching.

Although not all fasts lead to ketosis, ketosis can decrease inflammation and oxidative stress and help people lose weight. It may also reduce their risk of chronic diseases.

There are various intermittent fasting approaches, some popular options being the 5:2 diet and 16-hour overnight fasting. What people need to eat depends on which method they choose. Generally, they will either consume nothing or reduce their calories on some days or hours of the day.

When breaking a fast, there are no particular rules about what to eat for the best effects.

However, some experts advise people to eat a healthy Mediterranean diet.

Avoiding added sugars and refined carbohydrates may also help people lose weight.

However, people should only take part in longer fasts after consultation with a medical professional.