Perspectives That Go Beyond the Research
On January 16, 2025, The Lancet Commission released a report that challenges traditional methods of diagnosing and understanding obesity. Moving beyond Body Mass Index (BMI) as the sole metric, the report advocates for a more personalized and evidence-based approach. It defines clinical obesity as a chronic disease caused by excess adiposity affecting organ function, distinct from preclinical obesity, where excess fat does not yet cause health issues.
This shift aligns with the World Obesity Day theme, “Changing Systems, Healthier Lives”, emphasizing a need for systemic transformation in obesity care, diagnosis, and treatment. To better understand public sentiment, Obesity Matters and its French division, Parlons Obésité conducted a nationwide survey, collecting 166 responses from individuals across Canada.
What is BMI?
Body Mass Index (BMI) is a widely used tool to categorize individuals based on their weight relative to height. It is calculated using the following formula:
BMI = weight (kg) / height (m²)
Originally developed as a population-level measure, BMI provides a simple method for assessing body weight categories, including underweight, normal weight, overweight, and obesity. However, it does not directly measure body fat or overall health, which has led to concerns about its effectiveness as a sole diagnostic tool.
How to Measure BMI
Measuring BMI is straightforward:
- Weigh yourself in kilograms (kg) or pounds (lbs) and convert to kg (1 lb = 0.45 kg).
- Measure your height in meters (m) or inches (1 inch = 0.0254 m).
- Apply the BMI formula: weight (kg) / height (m²).
- Compare your result to standard BMI categories:
- Underweight: BMI < 18.5
- Normal weight: 18.5 – 24.9
- Overweight: 25 – 29.9
- Obesity: BMI ≥ 30
What is a Good BMI?
A “good” BMI varies based on individual health factors. While a BMI in the normal range (18.5 – 24.9) is often considered ideal, it does not necessarily indicate good health. Factors such as muscle mass, bone density, fat distribution, and metabolic health should also be considered. The Lancet Commission suggests that BMI should be used alongside other metrics to create a more comprehensive health assessment.
Community Insights: Awareness and Understanding of BMI
Survey results indicate that awareness of The Lancet Commission’s report was relatively low, with only 31.3% of respondents familiar with it. However, most participants demonstrated high familiarity with BMI, though many expressed concerns about its accuracy as a standalone measure of health.
A significant proportion of respondents—nearly 90%—felt that BMI alone is not an adequate indicator of overall health. Several participants noted that BMI does not account for factors such as muscle mass, fat distribution, and metabolic health. One individual shared, “BMI has never reflected my health. My fitness levels and blood markers tell a different story.” Another remarked, “BMI oversimplifies a complex condition and fails to capture the full picture of an individual’s health.”
Support for a More Comprehensive Diagnostic Approach
The Commission recommends including waist circumference, body fat assessments, and metabolic health indicators in obesity diagnoses. The survey reflected widespread support for this approach, with most respondents agreeing that a broader assessment could lead to improved accuracy and better patient outcomes. One respondent stated, “This approach could finally ensure that individuals are assessed on more than just their weight.”
Experiences with Healthcare and Access to Treatment
Discussions surrounding BMI in healthcare settings generated mixed responses. While some respondents reported that BMI was not discussed in their consultations, those who did encounter it had varying experiences. Some described instances where BMI was used to justify treatment recommendations, while others felt that it led to stigma or dismissal of their health concerns. One individual shared, “My doctor told me my health issues were solely due to weight, even though my lab results were normal.”
Regarding treatment accessibility, opinions were divided. While some respondents felt that the Commission’s new framework might improve access to care, others were uncertain whether healthcare and insurance systems would adapt accordingly. One participant questioned, “Will insurers recognize these new criteria, or will new barriers emerge?” Meanwhile, others expressed optimism that a more comprehensive diagnostic system could lead to better-targeted treatments and improved patient care.
Stigma and the Need for Personalized Care
The issue of weight stigma in healthcare was also a recurring theme. Many respondents reported experiencing bias when seeking medical care, reinforcing concerns about the limitations of BMI-based diagnosis. When asked whether moving beyond BMI could reduce stigma, over half of respondents agreed. Additionally, 63% felt that BMI contributes to negative biases in healthcare. One respondent reflected, “Perhaps a new system will help individuals be seen as whole people rather than just numbers on a scale.”
Health Concerns and Support Needs
Participants highlighted several key concerns related to obesity, including access to effective treatments, managing related health conditions, and the psychological impact of weight stigma. Many expressed a need for better access to obesity care, improved physician training, and expanded mental health support.
Looking Ahead: Implications of The Lancet Commission’s Report
The findings from this survey reflect the broader conversation around obesity diagnosis and management. The Lancet Commission’s report underscores the need for a more nuanced approach, moving away from reliance on BMI alone. However, the effectiveness of these changes will depend on how they are implemented within healthcare systems and whether they lead to meaningful improvements in access to care and patient outcomes.
Obesity Matters remains committed to providing a platform for informed discussions on obesity research, healthcare policies, and patient experiences. As the conversation around “Changing Systems, Healthier Lives” continues, it will be essential to track how these proposed changes are adopted and their impact on individuals living with obesity.