Obesity is defined as abnormal or excessive fat accumulation in the body that often leads to health risks in the long term. The most widely accepted standard for classifying obesity is the Body Mass Index (BMI). BMI is calculated by dividing a person’s weight in kilograms by the square of their height in meters (kg/m²). According to the World Health Organization (WHO):
A muscular individual may have a high BMI but low body fat, whereas someone with a “normal” BMI may have a high percentage of body fat, especially visceral fat, which increases cardiometabolic risk. Therefore, BMI alone is insufficient for a comprehensive obesity assessment.
Tools like waist circumference (WC) and waist-to-hip ratio (WHR) provide crucial insight into central obesity. A WC >102 cm in men and >88 cm in women is associated with a significantly higher risk of cardiovascular disease and type 2 diabetes. Additionally, body composition analysis using methods like bioelectrical impedance or DEXA scans helps quantify fat mass, lean body mass, and visceral fat levels, allowing for more targeted interventions.
Obesity is not just about how much fat is stored but also where it’s stored.
Visceral adiposity, often seen in central or abdominal obesity, poses a more significant health threat than general weight gain. This underlines the importance of incorporating imaging and anthropometric tools in routine assessments.
Ethnic background plays a crucial role in how obesity is expressed and its associated risks. For instance, Asian populations tend to develop central obesity and metabolic complications at lower BMIs compared to Western populations. Age is another important factor. With aging, muscle mass declines and fat mass increases, even when BMI remains stable. This leads to sarcopenic obesity, where reduced muscle function coexists with excess fat, requiring nuanced clinical approaches.
Understanding these classifications and their implications is essential for delivering individualized care and avoiding underdiagnosis or mismanagement. A deeper, more accurate classification of obesity enhances not only risk prediction but also the effectiveness of therapeutic interventions.
Obesity is not simply the result of excessive calorie intake or lack of physical activity. It is a complex, chronic disease influenced by hormonal, neuroendocrine, genetic, and inflammatory mechanisms that affect energy balance, metabolism, and fat storage.
Leptin, secreted by adipose tissue, signals the hypothalamus to suppress appetite and increase energy expenditure. In obesity, although leptin levels are high due to increased fat mass, leptin resistance develops, impairing satiety signaling and promoting continued weight gain.
In contrast, ghrelin, known as the "hunger hormone," is produced by the stomach and stimulates appetite. Obese individuals often have dysregulated ghrelin secretion, contributing to increased food intake.
Additionally, insulin resistance, a hallmark of obesity, develops as visceral fat accumulates. This reduces the body’s ability to utilize glucose efficiently, setting the stage for type 2 diabetes and metabolic syndrome.
While environmental factors, such as sedentary behavior, poor diet, and maternal obesity during pregnancy, play a key role, in some cases, genetics also plays a key role in body weight. Understanding the underlying biology of obesity helps plan simple, evidence-based management for obese individuals.
Obesity management requires a multimodal approach, which integrates nutritional, behavioral, pharmacological, and in severe cases, a surgical (bariatric treatment) approach. Healthcare professionals need to understand the core components and gain mastery over them to deliver improved patient outcomes.
Effective obesity management requires a comprehensive, patient-centered approach that addresses not just weight loss but long-term health and behavior change. Nutritional counseling remains the cornerstone, focusing on creating a sustainable calorie deficit through personalized meal planning and balanced macronutrient intake. This is complemented by structured physical activity, ideally at least 150–300 minutes of moderate-intensity exercise weekly, tailored to individual preferences and physical limitations. Together, these lifestyle modifications form the foundation of care.
Equally important is behavioral support through methods like cognitive behavioral therapy (CBT) and motivational interviewing, which help patients build self-awareness, improve coping strategies, and stay committed to lifestyle goals. In cases where lifestyle changes alone are insufficient—particularly in individuals with a BMI ≥30 or ≥27 with comorbidities—FDA-approved medications can assist in appetite regulation and metabolic improvement. For those with severe obesity (BMI ≥40 or ≥35 with complications), bariatric surgery may offer significant and sustained benefits, though it requires lifelong monitoring.
A multidisciplinary team, including physicians, dietitians, psychologists, physiotherapists, and surgeons, plays a vital role in delivering integrated care. This team-based approach ensures that both the physiological and psychological aspects of obesity are addressed, increasing the likelihood of long-term success and improved patient outcomes.
Obesity remains one of the most untreated or unaddressed aspects in primary healthcare settings. If weight management is done at the ground level, a physician's scope of controlling the risk of many NCDs becomes broader, which eventually leads to better health outcomes. By integrating obesity management in regular practice, by simple steps like measuring waist circumference, providing an evidence-based nutrition plan, and counseling on lifestyle changes, and by coordinating with a multidisciplinary team.
This is where structured learning becomes essential. A focused course like the Essentials of Obesity Management by Medvarsity equips clinicians with a practical, scientific, and holistic framework for managing obesity. From understanding pathophysiology and behavior change techniques to pharmacological options and surgical criteria, this course covers the full spectrum of care. It is designed for busy healthcare professionals, offering flexibility without compromising depth.
Doctors who upskill in this domain improve patient outcomes and also build trust, enhance their practice, and contribute to reversing a global health crisis. As the burden grows, so does the responsibility on healthcare providers to respond with confidence, competence, and compassion. Evidence-based obesity care is currently a clinical imperative.