Fad Diets and Effect on Metabolic Health
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Fad Diets and their effect on Metabolic Health

Fad diets are often taken up to lose weight rapidly. However, these diets do not take into consideration the nutritional needs of the body and are not backed by any scientific knowledge and gain popularity only because of celebrity endorsements and promotional material. Fad diets are usually temporary weight loss solutions, and you are bound to regain the weight you lost once you stop the diet. They are generally highly restrictive and can have a detrimental effect on your health in the long run. 

What are the identifying features of a Fad Diet?

  • They are promoted as quick-fix diets. 
  • They promise to give you drastic results in only a few days. 
  • They usually restrict or eliminate certain foods and food groups. 
  • The calorific value of these diets is severely restrictive. 
  • These diets promote rapid weight loss, detoxification, fasting or cleansing. 
  • They may suggesting replacing a meal with liquids. 
  • They are based on a single research study or personal experience. 
  • They forbid one particular macronutrient or, in some cases, overly encourage it. 
  • They have rigid rules that cannot be changed. 

One of the best ways of identifying if a diet is a fad diet is to ask yourself if you will be able to sustain the diet in the long term. If the answer is no, then it is sure to be a fad diet. 

What is Metabolic Health? 

A person is said to be metabolically healthy when all five critical parameters, such as the levels of blood sugar, high-density lipoprotein (HDL) cholesterol, triglycerides, blood pressure and waist circumference, are within ideal levels without using any form of medications. As metabolism and metabolic health have a close connection with nutrients, this form of diet can hurt an individual’s metabolic health in the long run. 

Effect of Fad Diets on Metabolic Health

Fad diets can have a lasting impact on the metabolic health of our bodies. Some start as soon as three days into the diet, while others can be experienced later. 

1. Reduced Thermic Effect

When you eat food, the body expends energy to digest, absorb and store the nutrients from the food. While beginning a new restrictive diet, your body will reduce its thermic effect as the food you consume is limited. The thermic effect is the increase in metabolism that occurs after the ingestion of your food. 

2. Lowered Resting Metabolic Rate (RMR)

RMR is the rate at which a body can burn energy when it is at rest. As your weight reduces, the RMR also reduces. RMR is an essential value as this is what determines your energy levels during the day. It accounts for almost 60 % of the total energy expended by the body in a day. It also helps to estimate the number of calories needed in a day based on the calories burned when the body is at rest. 

3. Decrease in Non-exercise Activity Thermogenesis (NEAT)

NEAT is the amount of calories that we burn while carrying out our day-to-day activities such as breathing, eating and sleeping. This value also reduces when you start a crash or fad diet.

4. Hunger Signals start accumulating. 

Once this starts to happen, you begin to crave various foods, and you may start feeling more and more hungry and overwhelmed. 

5. Slower Metabolism 

When the calorific value of your daily diet goes too low, then the body automatically goes into starvation mode, and the metabolism slows down to conserve energy. As the body is now metabolising slower, you may put on more weight once you go back to your regular dietary habits. 

6. Nutrient Deficiency 

As you limit yourself to eating only a specific type of food, you may miss out on other nutrients you need to keep your mind and body healthy. 

7. Digestive issues 

Anyone who has ever followed a fad diet can relate to the digestive issues that are very common with such diets. You may experience bloating, indigestion, constipation, and/or diarrhoea. The good microbes that are present in the gut also get affected, which in turn lowers their ability to keep the gut healthy.

How to have Healthy Eating Habits? 

As essential as eating right is for your body, is it just as scary and filled with indecision. The nutritional needs of two people will never be the same as it differs based on the individual’s age, genetics, fitness goals, and pre-existing health issues. You need to set your fitness goals realistically and choose the right nutritional plans to ensure optimum nutrition while you lose weight the healthy way. 

1. Nutritional Plans 

Having a nutritional plan will help you stay on track and induce accountability. They also give you all the nutrition you need throughout the day so that you do not crave ready snacks like chips or sweets. Setting long term goals and then making weekly or bi-monthly plans can help you reach your target better. 

2. Know your Macro and Micronutrients

There are two main categories of nutrients — macronutrients (Carbohydrates, proteins and fats) and micronutrients (vitamins and minerals). While macronutrients are the building blocks of muscle and tissue, they are also the primary sources of energy for the body. Getting the right amounts of macronutrients per day can ensure that you are energetic and have a solid and healthy body. On the other hand, micronutrients are essential in the body in smaller amounts and thus tend to get overlooked, leading to a deficiency of one or more of these micronutrients.


Now that you know how harmful fad diets can be to your body in the long run, it is best to avoid the urge for a quick fix and put in the time and energy you need to ensure that you healthily lose weight. Creating a diet plan can help you make sure that you get everything your body needs in the right amounts.

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  • https://www.betterhealth.vic.gov.au/health/healthyliving/weight-loss-and-fad-diets


This website's content is provided only for educational reasons and is not meant to be a replacement for professional medical advice. Due to individual differences, the reader should contact their physician to decide whether the material is applicable to their case.