Fast Diet: Advantages, Disadvantages, Types and Risks

Diets represent a resource, along with the practice of sports, when we want to improve health and physical appearance.

But on important occasions we require some quick results in the physical aspect so we look for an emergency regimen to lose weight and opt for the so-called “fast diets”.

Fast diets have disadvantages and advantages that must be assessed when choosing the method to lose weight.

Most diets achieve a decrease in weight and volume, but not fat, because they concentrate on suppressing excess accumulated liquids.

A fast diet should not be maintained for a long time, since they are usually very strict and involve large nutrient restrictions.

Advantages and disadvantages of the Fast Diet

All these diets to lose weight in a short time, have their advantages and disadvantages that must be known before starting a diet and evaluate them avoiding problems in the future.

  • Advantage

This type of regimen offers the opportunity to achieve a very rapid weight loss.

The type of foods allowed are very low in calories, they do not contribute sugars or fats to the body.

When there is no carbohydrate intake, the body uses fat reserve tissue for its metabolic functions

  • Disadvantages

Most of these diets are unbalanced, usually based on a single nutritious element: proteins, in the diet of Dr. Atkins, or hydrates and fats in the South Beach diet.

They are regimens that can only be followed for a short time due to their nutritional deficiencies.

Most of the weight lost is due to the elimination of liquids contained in the cells.

The foods recommended by these regimens provide very little caloric content.

Once the diet is finished, the rebound effect occurs.

They can cause kidney or liver problems, as is the case of diets with high protein contents.

They do not modify the alimentary habits that allow to practice these regimes for a long time.

They can produce hypercholesterolemia, since many of these diets recommend foods with high levels of fats, such as the ketogenic diet.

Types of Fast Diet

There are balanced diets to reduce body weight, which are low in calories and are based on a combination of foods.

In order to provide the body with all the necessary nutrients that allow weight loss in a healthy way and without unwanted effects.

Others such as fast diets, which are highly restrictive and that are not only reduced in calories but also in most of the nutrients that the body needs to perform their metabolic functions.

These diets should only be followed in specific cases because they involve a risk of having the rebound effect.

Among these diets we have:

Apple diet

The diet lasts only four days.

The first day you can only consume liquids and eat the apple, either in juices or whole.

In the other three days are included progressively: vegetables, proteins such as cheese, soy, to introduce all the food sets in small quantities, with the apple as the main food.

Liquid diet

The liquid diet consists in detoxifying the organism, and all the foods that are consumed in liquid form, these foods do not accumulate in the intestines and are easier to digest.

This diet lasts five days and all food will be consumed in the form of juice, smoothie, cream and puree, and both plant and animal origin foods may be consumed.

Diet 5-2

In this diet for seven days alternating 5 days of meals to taste, avoiding excesses and 2 days in which a semi-fast is performed, in which the total of food eaten daily, should not be higher than 500 cal.

They can be eaten either in a single meal or distributed throughout the day, and should be consumed foods with low caloric content but that give the impression of satiety.


Most fast-diet regimens use methods involving creams, pills, starvation, dietary supplements, meal plans with very low calorie content and devices.

Which cause adverse effects such as:

Gallstones, dehydration, malnutrition, electrolyte imbalances, headaches, irritability, fatigue, dizziness, constipation, menstrual irregularities, hair loss and loss of muscle mass.