Health Reports, March 2026

Released: 2026-03-18

Almost one in five Canadian adults have obesity with at least one indicator of obesity-related impairment

New analysis, based on data from the Canadian Health Measures Survey (CHMS) from 2016 to 2019 ,provides the first population-level estimates of obesity that incorporate indicators of organ and tissue dysfunction, and limitations in daily activities. In the study "Assessing obesity beyond body mass index: Integrating physiological and functional indicators of impairment in national health surveillance" obesity, also referred to as excess adiposity, is defined as body mass index (BMI) in the obese range combined with elevated waist circumference. This approach reflects the 2025 recommendations of The Lancet Diabetes & Endocrinology Commission, which emphasize defining obesity based not only on excess adiposity but also on objective indicators of obesity-related ill health. The results of this study provide an important baseline for monitoring future trends in obesity-related physiological and functional indicators of impairment.

Obesity-related impairment

To assess obesity-related impairment, the study examined physiological dysfunction and activity limitation across eight domains: upper airways, respiratory, cardiovascular, metabolism, renal, liver, musculoskeletal and activities of daily living.

Clinical assessment was not available to confirm that the indicators of impairment measured in the CHMS were attributable to obesity. Therefore, a tiered classification system was used to define clinical obesity, applying progressively stricter criteria across three tiers. At Tier 1, clinical obesity required excess adiposity plus an indicator of impairment in at least one domain. Tier 2 required indicators of impairment in two or more domains, and Tier 3 required indicators of impairment in at least three. At each tier, presenting fewer indicators of impairment than the corresponding threshold for clinical obesity was considered preclinical obesity.

Clinical and preclinical obesity prevalence

Over the 2016-to-2019 period, Tier 1 clinical obesity affected 19% of adults and an additional 8% had Tier 1 preclinical obesity. At Tier 2, the prevalence of clinical obesity was 12% and the prevalence of preclinical obesity was 15%. Tier 3 estimates were 7% for clinical obesity and 20% for preclinical obesity.

Evidence of obesity-related impairment varied across domains and across age and sex groups. Younger adults and females with excess adiposity were less likely to present with associated physiological dysfunction or activity limitation, suggesting opportunities for targeted prevention.

Implications for health surveillance

By incorporating measures of dysfunction and activity limitation, this study provides a more nuanced picture of obesity in Canada. Results also suggest that BMI remains an adequate indicator of excess adiposity in population-level surveillance when additional body composition data are unavailable. However, integrating elevated waist circumference and assessing excess adiposity alongside obesity-related dysfunction could strengthen public health monitoring and support more effective intervention strategies.

Products

The article "Assessing obesity beyond body mass index: Integrating physiological and functional indicators of impairment in national health surveillance" is now available in the March 2026 online issue of Health Reports, Vol. 37, No. 03 (Catalogue number82-003-X).

This issue of Health Reports also contains the article "Validating the Warwick-Edinburgh Mental Well-being Scale for the positive mental health surveillance of adults in Canada."

Contact information

For more information, or to enquire about the concepts, methods or data quality of this release, contact us (toll-free 1-800-263-1136; 514-283-8300; infostats@statcan.gc.ca) or Media Relations (statcan.mediahotline-ligneinfomedias.statcan@statcan.gc.ca).