Why Do Crash Diets Fail?

Crash diets are one of the popular eating plans today, but there are loopholes to this. Find out why this meal plan fails in the details below.

RELATED: What You Need To Know About Fasting, Starvation Diet, And Caloric Restriction

In this article:

  1. What Are Crash Diets?
  2. What Are the Different Types of Popular Crash Diets?
  3. Why Do People Call It Crash Diets?
  4. How Much Weight Can You Lose on Crash Diets?
  5. Are Crash Diets Good for Teenagers?

Reasons Why Crash Diets Won’t Work

What Are Crash Diets?

Before we talk about the reasons why crash diets fail, let’s first take a look at its definition to better understand what this eating plan is all about.

Fast crash diets are basically those meal plans with a very restrictive calorie requirement per day. It’s like cutting back your 1,000 calories a day to 500 only.

Crash diets may also mean eating one or two foods per week or simply doing juice cleansing. The period of the diet plan depends on the type of crash diet you are following, like a 3-day crash diet, but all of them have an end date.

What Are the Different Types of Popular Crash Diets?

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The following are the types of crash diets you may need to take note of:

  • Western Dietary Pattern

As the name implies, this diet promotes the Western type of meal plan. The foods introduced here are typically eaten in developed countries, such as puddings, milk, white bread, and meat.

  • Subway Diet

This crash diet allows a dieter to eat Subway sandwiches instead of fast foods high in calorie count.

  • Monotrophic Diet

This extreme dieting promotes consuming one food item or type for some time to reach the dieter’s desired weight goals.

  • Grapefruit Diet

This fad diet uses grapefruit to promote fat loss as the dieters consume the fruit in large quantities during mealtime.

  • Cabbage Soup Diet

It’s another fad diet which relies on consuming heavy amounts of cabbage soup to lose weight quickly.

  • Beverly Hills Diet

This low-calorie diet lets a dieter consume fruits only for the first few days. As the diet progresses, a dieter slowly increases the food choices until the 6th week.

Why Do People Call It Crash Diets?

A crash diet simply refers to the fast weight loss process in a particular period of the meal plan. You can see results immediately, but the problem is there is a high possibility you will gain your weight back after the diet period.

This can be ideal if you will attend upcoming events. But, crash diets are not basically for long-term purposes.

The diet may sound like a helpful weight loss program, but it won’t give you positive results long term. Here are the following reasons why:

1. Temporary Starvation Slows Down the Metabolism

Understandably, crash diets have long been popular with those who yearn to lose weight fast. There is no argument that starvation will result in weight loss.

But, what happens when we induce a metabolic starvation mode? Why do crash diets fail?

Simply put, temporary starvation slows down the metabolism. The basal metabolic rate declines, and our physiology slows down as well.

Not surprisingly, the dieter feels tired, sluggish, and cranky.

2. Extreme Metabolic Economy Leads to the Shrinking of Your Mitochondria

Here’s what is occurring behind the scenes of that promising new crash diet. Since the body must start consuming its reserve energy (fat), it enters a period of extreme metabolic economy.

This results in a metabolic fuel shortage, and your mitochondria tend to shrink and go “offline” in the interest of preserving this economy. If you keep to starvation mode long term through the ingestion of a very-low-calorie diet, the metabolism rebounds.

Typically, however, starvation mode ends, and food intake is resumed. You might think, “Hey, that doesn’t sound so bad for a dieter,” but you’d be wrong.

3. A Short Starvation Period Can Result in Rapid Weight Gain

Under the context of starvation-induced slow metabolism, the first priority of our physiology is to restore the reserves consumed. So, even resuming a “normal” calorie diet after a short period of starvation will result in rapid weight gain.

4. Crash Diets May Put Your Health at Risk

Starvation also puts your health at risk with other possible complications such as vitamin and mineral deficiencies, hormonal imbalance, and the potential for psychological and behavioral disorders related to food.

RELATED: “Mind” Your Diet For Better Brain Aging

5. The Brain and Central Nervous System Need Glucose, Not Fat

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If we have fat reserves, it seems like starvation would be good, right? Well, it’s not so simple.

The heart and skeletal muscles are efficient users of mobilized fat energy, but the brain and central nervous system are strict metabolizers of glucose, not fat.

So, during the starved state, the body focuses on making glucose for the brain, not mobilizing fat for the muscles. This keeps you alive, but muscle metabolism shrinks because mitochondria shrink in size and population.

This state is often referred to as a shrunken or slow metabolism, and it can have a lasting negative impact on your health. What’s the most irksome piece of this puzzle?

Your altered metabolism makes it easier to gain weight and hard to lose weight in the future. It’s exactly what you were trying to avoid!

6. You Will Miss Out on Taking Major Essential Nutrients

One downside to following a low-calorie diet is you will miss out on consuming many essential nutrients. You can’t make sure if you are getting enough B vitamins, iron, calcium, amino acids, fiber, or protein in most crash diets.

These are the “good stuff” your body needs for growth and development on a daily basis. Without enough of these nutrients, your blood cells, cognitive function, bone, and many other body parts and functions may suffer.

7. Dehydration Is Extreme

Crash diets like juicing may let you lose weight fast. This is because you are losing water weight from your body, but this is not ideal long term.

Glycogen stores, which are your energy source that binds water, deplete more quickly than fat cells responsible for water release. This can result in dehydration.

When you go back to your normal eating amount, your glycogen and water stores replenish, but weight gain follows.

8. Crash Diets Are Not Sustainable

Weight loss needs time to fully get rid of excess fat, especially if you gained weight long term. You need to take note that crash diets do not deal with moderation.

These rapid weight loss diets have their own rules to follow, which include cutting out whole food groups. This significantly affects your social life because you have food limitations if you go to a loved one’s party.

You cannot enjoy what everyone is trying to enjoy. Aside from that, your appetite may also increase even after you had the diet because your body may try to compensate for the calorie loss during your meal plan period.

Crash diets are not sustainable like other long-term diets because they only make you lose weight when on the meal plan but cannot maintain their purpose after the eating plan period.

How Much Weight Can You Lose on Crash Diets?

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Crash diets can let you lose weight up to 10 pounds or 4.5 kg in a week. Their aim is to let you lose weight in a very short period, so it’s not a good idea to assume you are going to lose excess weight continuously.

If your purpose is long-term weight loss and to reach a desired weight for good, this diet may not be an option for you.

Are Crash Diets Good for Teenagers?

Weight loss diets are good for people who are overweight or obese and who want to achieve a healthy weight. But, it’s not ideal anymore to follow a diet if you only want to look and feel good, especially for teenagers.

Ages 13-19 years are in a growing phase, and following crash dieting may hinder their growth and negatively affect their mental health. But, if you need to really lose weight, again, it’s best to seek for a dietitian’s help and get your own diet chart that suits your nutritional needs.

Aside from that, diet alone does not make you lose weight completely because you also need to be physically active to be fit and improve muscle mass. The combination of a healthy diet and regular exercise is a wonderful way to achieve a healthy weight and lean muscle.

Crash diets might be tempting, especially if you want to lose weight quickly for an upcoming event. But, you need to consider its side effects if you want to achieve your body goals healthily.
The best way for you to lose weight healthily is to seek advice from a health professional so you know how to deal with your weight the right way.

Have you tried a crash diet? How was your experience? Tell us in the comments section below!

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Editor’s Note: This post was originally published on April 3, 2014, and has been updated for quality and relevancy.