World Obesity Day: What is obesity, why is it a problem, and the truth about fat loss

Obesity is a risk factor for health conditions like diabetes. Conversely, insulin resistance and diabetes are also risk factors for obesity. (Image: Julia Larson via Pexels)

The conversation around obesity and weight loss needs to rapidly evolve, to reflect a deeper scientific understanding of obesity, its health effects, why some people put on weight faster and have greater difficulty shedding it than others, and how to get to a healthier body and mind.

An easy and inexpensive way to diagnose obesity is to look at the body mass index - a BMI of 30kg/m2 or more is categorized as obesity. BMI measures the body's fat percentage relative to height and weight.

The fifth annual World Obesity Atlas, 2023 reported that approximately 2.6 billion people suffered from obesity in the year 2020. This number is expected to rise to more than 4 billion (excluding children under 5 years) by 2035. At this rate, the global economic burden of obesity will be US$4 trillion of potential income in 2035 (3 percent of the global GDP).

Reasons why more people are getting obese

Obesity is a multifactorial health condition. Some of the biggest factors for obesity, including genetic factors, are out of our control. The latest science is also pointing to how fat loss isn't just a matter of will power, and that fitness experts may have done a disservice to society by overemphasizing the usefulness of certain diets or exercise routine - if only people stick to them.

Having said that here are some reasons, including environmental factors, why people gain weight and have a high BMI:

1. Poor diet: Highly processed, cheap and high-calorie foods that are typically low on nutrition are easily available - what's worse, these high-salt, high-sugar, trans-fat-containing foods are designed to induce cravings. Prolonged, frequent or excessive consumption of these food items may result in obesity. Ultra-processed foods include ice-cream, chips, and most things that come out of ready-to-eat food packets.

2. Sedentary lifestyle: Long desk hours at work, lack of exercise and inactivity may be contributing factors for a number of health conditions, including obesity.

3. Lack of sleep and increased stress: Lack of sleep and high levels of stress can affect the hunger hormones that regulate our appetite, increase appetite or reduce the feeling of fullness, lower our energy levels during the day, making people more sedentary and posing them at a higher risk of resistance to insulin, a hormone that helps the body in metabolising carbohydrates.

4. Genetics: Genetic factors are correlated with the way the body metabolises food, regulates appetite hormones, stores fat and energy, and an individual’s behaviour around food choices and preferences. Hence, some people are at a higher risk of becoming obese than the others.

5. Medication: Medicine for certain health conditions may also result in weight gain in the long run. These include antidepressants, antipsychotics, steroids, medications for diabetes, heart disease and high blood pressure.

Overall, a combination of these factors has contributed to the global rise in obesity rates, which can lead to a range of health problems, including diabetes, heart disease, and certain types of cancer.

A global issue

The high prevalence of obesity worldwide can have a range of consequences, both for individuals and society as a whole. Here are some examples:

1. Health problems: Unhealthy weight gain can ultimately result in obesity, which increases the risk for developing a range of chronic and sometimes fatal health problems, including diabetes, heart disease, stroke, certain types of cancer, and joint problems. These health problems can have a significant impact on an individual's quality of life and may also reduce life expectancy.

2. Economic burden: As the Atlas 2023 suggests, obesity is not just associated with increased healthcare costs, it also reduces the overall productivity of the population. This can place a significant economic burden on society as a whole, including governments, businesses, and individuals.

3. Social stigma: Individuals who are obese often face discrimination and social stigma, which can lead to low self-esteem and productivity and overall quality of life. This can also contribute to mental health problems such as depression and anxiety. For some people, it can become a trigger for stress-eating.

The high prevalence of obesity is not limited to one country or region. It is a complex issue that requires cross-border collaborations between scientists and policymakers.