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Obesity is a growing health problem worldwide. 13% of adults worldwide considered obese and obesity is the cause of premature death for 4.7 million people in 2017. This was close to three and four times higher than estimated road accidents and HIV/AIDS respectively. Yes, obesity is a growing health concern worldwide. Unfortunately, there are still many misconceptions around what exactly obesity is and how to go about treating it.

What is obesity?

Obesity is a medical condition whereby a person carries excess weight or body fat that might negatively affect their health. The most common way to test if someone is obese is to use the Body Mass Index (BMI). This is a tool that doctors use to evaluate a person’s appropriate weight for their age, sex, and height. BMI is a person’s weight in kilograms divided by the square of their height in metres. A BMI between 25 and 29.9 shows that a person is carrying excess weight. A BMI of 30 or over indicates a person may have obesity.

Obesity is frequently subdivided into categories:

  • A Class 1: BMI of 30 to <35.
  • Class 2: BMI of 35 to < 40.
  • Class 3: BMI of 40 or higher. This is sometimes categorised as ‘extreme’ or ‘severe’ obesity. obesity

What causes obesity?

Obesity being purely caused by a lack of physical activity and an unhealthy diet is a common misconception. Eating more calories than you burn is a major cause of obesity. However, there are other factors that can impact obesity including a lack of sleep and the so-called obesity gene.

Research has shown that sleep deprivation significantly impacts weight gain and obesity in both children and adults. This is because it leads to hormonal changes that stimulate appetite. A lack of sleep causes the body to produce more of the ‘hunger’ hormone ghrelin, resulting in an increased appetite. At the same time, a lack of sleep also decreases the production of leptin, the hormone that suppresses the appetite. The imbalance in these hormones could cause people to eat more resulting in increased weight gain.

 A faulty gene called the fat-mass and obesity-associated gene (FTO) is also responsible for some cases of obesity. FTO impacts the amount of ghrelin (the hunger hormone) a person produces. This might affect a person’s chances of having obesity. Ghrelin affects how the body stores fat. It might even play a role in eating conditions such as binge eating and emotional eating. This further impacts a person’s predisposition towards obesity. The FTO gene can also impact people’s eating habits, leading people to prefer high-calorie foods, having a higher intake of food, and an impaired ability to feel full. These are all factors that should be taken into consideration when diagnosing and understanding obesity.

Complications related to obesity

As obesity is a medical disease, it comes with several complications. Overweight and obesity are major risk factors for a number of chronic diseases, including heart disease and stroke, which are the leading causes of death worldwide. Obesity can further lead to diabetes and the conditions associated with diabetes complications such as blindness, limb amputations, and the need for dialysis. It also impacts the skeleton, and carrying excess weight can lead to musculoskeletal diseases including osteoarthritis. Obesity and being overweight can also lead to other diseases including hypertension, high cholesterol, many types of cancers, and mental illnesses such as clinical depression and anxiety.

What about the link between COVID-19 and obesity?

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According to Dr. Tobeka Boltina, head of Clinical, Medical & Regulatory Affairs at Novo Nordisk, obesity-related conditions seem to worsen the effect of COVID-19.

“The U.S. Centers for Disease Control and Prevention (CDC) reported that people with heart disease and diabetes are at a higher risk of COVID-19 complications.” explains Dr. Boltina, “Adults with obesity are, however, at an even greater risk during the COVID-19 pandemic, as having obesity increases the risk of severe illness from COVID-19, and obesity is linked to impaired immune function. Having obesity may triple the risk of hospitalisation due to a COVID-19 infection”

Persons with obesity who become ill may require intensive care and present challenges in patient management. Obesity reduces lung capacity and reserve and can make ventilation more difficult. It is more difficult to intubate patients with obesity.

In summary, an analysis of the findings from evidence published during the COVID-19 pandemic suggested that obesity was strongly associated with poor outcomes in patients who were infected with COVID-19. Patients living with obesity were at a higher risk of severe COVID-19, and disease progression, and showed an increased need for hospitalisation, ICU care, and ventilation. Efforts to better understand the impact of obesity on COVID-19 and the death of COVID-19 patients are ongoing.

Eating behaviours and stigma

In many countries around the world, weight stigmatisation and discrimination from society and family create psychological obstacles to obesity treatment. Growing evidence shows that weight bias can have a negative impact on people struggling with obesity and weight loss, leading to internalised weight bias and potentially disordered eating behaviours. Understanding the psychological reactions to weight and stigma could play a key role in treating obesity, including the knowledge of what causes obesity and exacerbates it, and how to treat obesity effectively.

How does maintaining a healthy weight protect one against complications?

“Treating obesity and each associated complication also contributes to the healthcare-related spend in South Africa, creating a burden to the country’s economy, ” explains Dr. Boltina. She goes on to add that a weight loss of 5 –10% is associated with significant clinical benefits which may include the following amongst others:



  • A reduction in risk of type 2 diabetes
  • A reduction in cardiovascular death
  • Improvements in cardiovascular risk factors such as blood lipid profile and
  • blood pressure
  • Decreased severity of obstructive sleep apnea
  • Improvements in health-related quality of life

It is therefore in the patient’s interest that obesity be treated early using an individualised treatment plan that encompasses multiple disciplines, to prevent complications or to reduce the negative impact of existing complications on a patient’s quality of life.

Treating obesity

There are a variety of treatment methods that can be used to help treat obesity, from changing diets and increasing physical activity to using weight loss medications, prescribed by a medical professional. As obesity is a complex medical condition, it is important that a healthcare professional is consulted when it comes to treating obesity, as each person requires a different approach based on their condition.

Diet and exercise

Dieting and physical exercise should be done carefully. Crash dieting should be avoided as it could cause new health problems or vitamin deficiencies, and can even make achieving weight loss more difficult.

People should do approximately 150 minutes of moderate exercise a week to have a positive impact on their weight and health.


obesityWeight loss medications can also play an important role in weight loss and will be prescribed by healthcare professionals if dietary changes and exercise have not resulted in weight loss, or a person’s weight poses a significant health risk. Weight-loss medications are not meant to replace lifestyle changes. However, they can supplement weight loss by aiding dietary changes and exercise.

Medications can assist with weight loss by focusing on the hormones that control hunger and the feeling of fullness. For example, GLP-1 (glucagon-like peptide-1) molecules are naturally occurring and can affect the body’s feeling of hunger after eating. There are studies focused on how synthetic GLP-1 molecules can potentially be used to suppress appetite or increase energy and kickstart potentially long-lasting weight loss. As obesity is a medical condition, medication can play a vital role in assisting people with weight loss.

A challenge to lose weight

The body reacts to losing weight by trying to regain the weight. Once you start losing weight, hormonal changes lead to increased feelings of hunger and decreased feelings of fullness as the levels of satiety hormones decrease and the levels of hunger hormones increase. These changes also result in fewer calories being burnt.

The SetPoint Theory states that every person has a certain ‘set’ weight that their body accepts and is genetically disposed to. Thus any attempts to lose weight results in the body’s survival instincts kicking in to regain weight to stay at that ‘set’ weight. These hormonal changes may last for up to three years. Additionally, it may be part of the reason why most people end up regaining lost weight in the long run. 

Obesity is a complex medical condition. It is the result of a variety of factors, not only a lack of physical exercise and unhealthy eating. Understanding these factors is an important step in tackling obesity and the misconceptions surrounding the disease. All the causes for obesity need to be considered and understood before treatment can occur. Due to the complex nature of obesity and weight loss, seeking the help of a health care professional, and creating a treatment plan tailored to individual needs is an important step in treating obesity.

Guest Writer

Guest Writer

This post has been curated by a Longevity Live editor for the website.


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