Morbid Obesity
Metabolic Health
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Morbid Obesity: A Complete Guide

Morbid obesity is also known as Class III obesity. The classification for proper weight requirements is based on Body Mass Index. BMI is calculated according to your height and weight. It is calculated by dividing the weight of a person in kilograms by height in meters squared.  Below is the BMI classification:

BMI       Classification
<18.5     Underweight    
18.5 - 25 Healthy        
25 - 30   Overweight    
>30       Obese          

What Is Morbid Obesity?

Obesity is further classified into 3 classes. Class 1 obesity is classified between 30 to 34.9. Class 2 obesity is classified when the BMI is between 35 to 39.9. Morbid obesity BMI is when the BMI is more than 40. Class 3 obesity is also known as morbid obesity. It is a complex chronic disease that causes more health problems. Although BMI is not the most accurate way to measure the health of a body, it is a good indicator of how much you should weigh. 

How is Morbid Obesity caused?

Whatever you eat gets broken down into calories which the body uses for daily functions. The body needs calories for every bodily function starting from pumping the blood to physical acts like walking, sitting, and so on. Even when you are asleep, you end up spending a few calories. When the body does not spend the number of calories it ingests, it starts storing it in the body in the form of fat. When the fat keeps accumulating, the weight increases and it causes morbid obesity. 

What are the symptoms of Morbid Obesity? 

There are no classic symptoms of Morbid obesity BMI. The only sure way to identify morbid obesity is by calculating the BMI. A lot of healthcare providers consider other factors such as waist circumference and body fat distribution. Class 3 obesity can cause multiple complications and have adverse effects on the body. 

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Who is at risk?

There isn’t a proper way to determine who might be at risk for obesity. Here are some other factors that can be indicators of morbid obesity.

1. Genetic predisposition

This is a common factor. Obesity can run in families and the next generation is prone to weight gain even when they lead a healthy lifestyle. They may need to work extra hard or be vigilant when it comes to weight gain. 

2. Hormone imbalances

Hormones in the body have a specific function and when there is an imbalance it can cause weight gain. For example, cortisol, also known as the stress hormone, is essential for the body’s fight-or-flight response. When you are constantly under stress, your appetite increases but you don’t end up burning all the calories. Hypothyroidism can lead to weight gain as well.

3. Spending power and geographical factors

In today’s age, it is much easier to get processed foods and they are much cheaper compared to the healthy and organic foods available. This can contribute to weight gain and makes a lot of difference in the long run. If there is no access to a place where one can exercise, walk, and spend energy, it can be difficult. 

4. Medications

Apart from an inconsistent lifestyle, there are many medications that cause weight gain and lead to morbid obesity. Antidepressants are known to cause weight gain. 

5. Cultural elements

Marketing and exposure to advertisements that promote processed or packaged foods can affect one’s eating habits and contribute to developing obesity. 

5. Environmental elements

Exposure to certain chemicals can change your hormones and increase the storage of fatty issues in your body. This can lead to class 3 obesity. 

Apart from these factors, mental well-being also plays a large part in keeping weight under check.

How is Morbid Obesity diagnosed?

Most medical professionals diagnose morbid obesity by taking a look at the BMI. BMI is the weight-to-height ratio that determines whether one falls under the classification of obese. An adult may be considered class 3 obese if they meet any of these criteria. 

  • If a person is more than 80-100 pounds above their ideal body weight then they are referred as  super morbidly obese. 
  • A BMI of 40 or more indicates morbid obesity. 
  • A BMI of 35 or more with health issues like high blood pressure, diabetes, and so on is an indication of morbid obesity. 

BMI is not the only yardstick to measure one’s health. For example, there is a different scale to check the weight-to-height ratio of children. Healthcare providers may also consider the circumference of the waist to determine whether a person is obese or not. The scale for pregnant ladies is different and the scale for males and females is different in general. There may be differences in standards for measuring obesity based on ethnicity as well. 

Some medical professionals also consider the thickness of the skin in these areas of the body –

1. Triceps

2. Biceps

3. Under your shoulder blades

4. Above your hip bones

Apart from this, there are some doctors who recommend getting a few tests done to get a definitive answer. Some of these tests are – 

  • Complete blood count or CBC
  • Metabolic Panel
  • Kidney function test
  • Liver function test
  • Lipid panel
  • Hemoglobin A1C(HbA1c)
  • Vitamin D levels test
  • Thyroid stimulating hormone test
  • Urinalysis

Risks & complications of Morbid Obesity caused

Those who are super morbidly obese face a long list of health issues. Here are some of the common ones experienced by those who are morbidly obese meaning they have a BMI higher than 40.

1. Diabetes

Type 2 diabetes is very common due to the increased insulin resistance in the body. This can be maintained using exercise and proper diet, and medication. 

2. Heart-related ailments

An increase in weight can be stressful for your heart as it needs to work overtime to pump blood throughout the body. In addition to proper circulation, the walls of arteries can get smaller due to fat deposits making the person at risk for stroke, heart attacks, hypertension, and other such cardiac ailments. 

3. Lesser life expectancy

Being obese may shave off a few years of your life due to the increase in health issues that come with it. 

4. Osteoarthritis

Your joints are burdened due to the unnatural increase in weight they have to carry which leads to wear and tear. The bones cannot take the weight and it can lead to inflammation, and eventually permanent damage. 

5. Respiratory problems

The increase of fat deposits around the neck and chest can suppress your airways and make it more difficult for you to breathe. 

6. Depression

This can be the cause and risk of class 3 obesity. It can be a greater risk when it gets added to a list of things that need medication. 

7. Infertility

This is a concern because of the unbalanced hormone levels and physical strain on the reproductive organs. 

8. Urinary stress

The added pressure on your urinary tract, and kidney, make it harder to hold in the urine when you sneeze, cough, laugh, or jump. 


There is no firm data on weight loss treatments for morbid obesity. Here are some of the ways people have lost weight effectively. 

1. Changes in diet and exercise

This is the healthiest way to lose weight and gradually drop those extra pounds. You can work with a trainer, dietitian, and your doctor to understand what your body needs and set realistic goals for you to achieve in a positive manner. The stress to lose weight can cause a reverse effect and you need to work with a team that has a positive attitude. 

2. Weight loss drugs

There may be medications that can cause you to lose weight. These should not be taken without a prescription from the doctor. Many people faced the issue of gaining weight back immediately after they stopped taking medicines. There may be some herbal supplements that claim to help you lose weight but ensure you are checking for proper approvals before you take any medicines. 

3. Better sleep schedules

If you have an issue with sleeping or sleeping soundly, you may gain weight as obesity has often been linked with lack of sleep. 

4. Stress management

Extreme stress can lead to weight gain. It is important to find a way to deal with stress in a healthy and mindful way. You can try breathing exercises or yoga. 

5. Psychological therapy

There are ways to change the mindset of the person with morbid obesity to ensure they have a healthy attitude towards losing weight. Motivational interviewing is a type of therapy that helps change behavior by gaining perspective about yourself. Cognitive Behavioral Therapy works with you to change your thinking and behavioral patterns that are negative. Dialectical Behavioral Therapy specializes in dealing with a self-destructive pattern

6. Surgery

Surgery is the most invasive option to lose weight. There is no guarantee of a long-term weight loss solution that involves surgery. This can cause complications and it should be considered after gaining all the information. Gastric Banding Surgery or Gastric Bypass Surgery is the most common ones that people opt for. 


Morbid Obesity or Class 3 obesity is just like any other health issue that should be arrested in time. It can be managed and the corresponding health issues can be managed too. There are many ways to lose weight and bring it back on track but the healthiest and most effective one with long-term effects is a proper diet and a rigorous exercise regime. 


1. What is the difference between obesity and morbid obesity?

Obesity is determined by the BMI of a person. BMI above 30 is classified as obese. However, class 3 obesity or morbid obesity is when the BMI is more than 40. 

2. How long do morbidly obese live?

There is no particular age defined to which morbidly obese live. However, studies show that their life expectancy is shorter than healthy people. 

3. Can morbidly obese lose weight?

Yes, morbidly obese meaning those with BMI higher than 40 can lose weight and there are lot of ways they can employ to do so.


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.