Morbid Obesity, also known as Class III Obesity, is a serious medical condition characterized by excessive and unhealthy amounts of body fat that may have a detrimental impact on an individual’s health. Alongside being classified as a chronic disease, it is also one of the leading causes of preventable deaths worldwide. Class III obesity is a complex and multifactorial disorder, and is often associated with numerous comorbidities including cardiovascular disease, type 2 diabetes, musculoskeletal complications, and sleep apnea. In this article, we will discuss the symptoms, causes, diagnosis, treatment options, prevention, and complications of class III obesity whilst also giving insight on how to live with obesity.

Symptoms of Class III Obesity

The symptoms of class III obesity are often characterized by the presence of an excessive and unhealthy amount of body fat, which can be measured via body mass index (BMI). BMI is a measure of body fat based on an individual’s height and weight. For adults, those with a BMI greater than or equal to 40 are considered to be morbidly obese. Children and adolescents are assessed using percentile ranges, with a BMI greater than or equal to the 95th percentile being considered obese.

Alongside this, some common symptoms of Class III Obesity include difficulty in physical activity, hypertension, shortness of breath, joint pain, and emotional stress. These symptoms can severely impact an individual’s quality of life, social interactions, and physical and mental health.

Symptoms of Class III Obesity

Causes and Risk Factors

Class III obesity is often a result of a complex interplay between various genetic and environmental factors that can lead to an excessive accumulation of body fat over time. Many factors can contribute to the development of class III obesity, including genetics, dietary intake, sedentary lifestyle, and medical conditions such as hypothyroidism, Cushing’s syndrome, and polycystic ovary syndrome (PCOS).

Additionally, various social and cultural factors such as low socioeconomic status, limited access to healthy foods, inadequate education, and other environmental factors can also play a significant role in the development of class III obesity. Evidence also suggests that stress and mental health issues, such as depression and anxiety, can further contribute to the development of obesity.


Class III obesity can be diagnosed through a physical examination, personal and family medical history, and various laboratory tests, such as blood tests and imaging studies. Through these tests, healthcare providers can identify the underlying causes of the obesity and assess the possible complications and comorbidities, such as high blood pressure, type 2 diabetes, and heart disease.

Treatments for Severe Obesity

Class III obesity can be challenging to manage, and it requires a comprehensive and individualized treatment plan. The primary goal of treatment for Class III obesity is to achieve sustainable weight loss and improve overall health. There are a variety of treatment options available, including lifestyle changes, medications, surgery, and devices.

Treatments for Severe Obesity

Lifestyle Changes

One of the fundamental treatment approaches for Class III obesity is to promote a healthy lifestyle through regular physical activity, a nutrient-dense diet, and behavioral modifications, such as cognitive-behavioral therapy. These changes can often result in modest weight loss and can provide numerous health benefits, including the prevention and management of chronic diseases.

Treatments for Severe Obesity


Medications may be prescribed to individuals with Class III obesity if lifestyle interventions are ineffective. These medications can help to promote weight loss and reduce the risk of medical complications. However, the use of medications for the treatment of obesity is typically reserved for individuals with a BMI greater than 30 and for those who have obesity-related comorbidities.


If lifestyle modifications and medications have not produced favorable results, your healthcare provider may suggest weight loss surgery. The objective of weight loss surgery is to decrease the size of your stomach and induce a sensation of fullness more quickly after meals.

Individuals with severe obesity (those with a BMI exceeding 40) may find weight loss surgery beneficial. Your healthcare provider might also recommend surgery if you are dealing with additional health issues such as heart disease or sleep apnea.

If weight loss surgery is deemed suitable for you, your provider may propose one of the following procedures:

Vertical sleeve gastrectomy: A procedure in which most of the stomach is removed, leaving behind a small, banana-shaped pouch. This type of surgery is non-reversible.

Gastric bypass: A surgical process involving the stapling of the top section of the stomach to create a small pouch, which is then connected to the middle part of the small intestine. Reversing this type of surgery is challenging.

Adjustable gastric band: A surgical method in which an inflatable band is placed around the upper part of the stomach to form a small pouch. This type of surgery can be altered or reversed as needed.


In addition to medications and surgery, medical devices such as gastric balloons, stomach electrical stimulators, and duodenal-jejunal bypass liners can also assist in the management of Class III obesity.

Prevention and Complications
Class III obesity can lead to numerous complications, including cardiovascular disease, stroke, hypertension, type 2 diabetes, and certain cancers. Thus, prevention is crucial in managing class III obesity. Implementation of a healthy lifestyle, including regular physical activity, maintaining a balanced and nutrient-dense diet, and stress management, may prevent the onset and health consequences of the condition.

Living with Obesity

Living with Class III obesity can be challenging, physically, and mentally. Therefore, it is essential for individuals with Class III obesity to seek professional help for not only weight management but also the management of any comorbidities and mental and emotional health concerns that may come along with this condition. Studies have shown that support from healthcare providers, family, and peer groups can positively impact mental and emotional health and provide motivation and encouragement for weight loss and lifestyle modifications.
(To learn about Obesity Management , please refer to this article)


Class III obesity or morbid obesity is a chronic condition that affects millions of people worldwide and is often associated with numerous comorbidities and complications. Various factors, including genetics, health behaviors, environmental, and social factors, can contribute to the development of Class III obesity. While treatment options such as lifestyle changes, medications, surgery, and devices are available, prevention and early intervention remain essential in mitigating the health consequences of Class III obesity. Moreover, individuals living with Class III obesity must seek professional help to manage the physical, mental, and emotional aspects of this condition.

According to statistics, approximately 13% of the global population is affected by Class III obesity. In the United States alone, the prevalence of obesity and severe obesity has increased substantially in recent years, with recent data from the Centers for Disease Control and Prevention (CDC) reporting that 42.4% of adults in the U.S are obese. The increased prevalence of Class III obesity comes with increased healthcare costs and morbidity and mortality rates. Thus, there is an urgent need for comprehensive public health interventions that address the complex and multifactorial nature of Class III obesity.


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