We have detected that you are located in . Do you want to switch to the local site?
Obesity is now recognised as a chronic disease, or in other words a long-lasting condition, due to an excess amount of body fat.1-3 Chronic diseases often limit activities and daily living, and may require ongoing medication.4 Obesity is linked to other chronic diseases, such as heart disease, cancer, stroke, diabetes and many more — in fact, more than 200 medical conditions. It's also a serious condition (with its own symptoms, complications and causes) on its own.3,5
To find out if you're living with overweight or obesity and to get a formal diagnosis, it's important to talk to your doctor. One simple way to screen for obesity is to calculate your Body Mass Index (BMI).
The Body Mass Index (BMI) classifies underweight, overweight and obesity in adults based on their height and weight as follows:6
| BMI classification | Underweight — Below 18.5 kg/m² |
| Normal — 18.5–24.9 kg/m² | |
| Overweight — 25.0–29.9 kg/m² | |
| Obesity Class I — 30.0–34.9 kg/m² | |
| Obesity Class II — 35.0–39.9 kg/m² | |
| Obesity Class III — Above 40 kg/m² |
It's also important to know that this classification can vary in certain ethnic groups, such as Indigenous Peoples, South Asians, Chinese and other populations. Always check with your healthcare professional about the suitability of this BMI classification based on your own circumstances.6
If you are living with overweight or obesity, having an excess amount of fat on the body is the most obvious symptom. But there are also other symptoms you may experience. These can include:3,7-10
If these symptoms sound familiar, it may be a good idea to talk to your doctor. Understanding how your weight may affect you will be helpful when you explore what you can do to lose it and keep it off.
Understanding your weight is the first step. Our discussion guide can help you prepare for a productive conversation with a doctor about weight management.
Essential tools to monitor your health and have productive conversations with a doctor.
Talk to a doctor about treatment options that could help prevent the weight you lose from coming back.
Bray GA, et al. Obes Rev 2017;18(7):715–723.
World Obesity Federation. Obesity as a disease. Available at: hwww.worldobesity.org/what-we-do/our-policy-priorities/obesity-as-a-disease. Accessed May 2025.
World Health Organisation. Obesity and overweight. Available at: www.who.int/news-room/fact-sheets/detail/obesity-and-overweight. Accessed May 2025.
Lobstein T, et al. World Obesity Atlas 2022. London: Ludgate House, 2022.
Yuen M, et al. A systematic review and evaluation of current evidence reveals 236 obesity-associated disorders (ObAD). Poster T-P-3166 presented at Obesity Week 2016, 31 October – 4 November, New Orleans, LA, USA.
Rueda-Clausen CF, et al. Canadian Adult Obesity Clinical Practice Guidelines: Assessment of People Living with Obesity. Available at: obesitycanada.ca/guidelines/assessment. Accessed May 2025.
Yuen M, et al. A systematic review and evaluation of current evidence reveals 195 Obesity-Associated Disorders (OBAD). The obesity society 2016 abstract book 2016:92.
Christensen R, et al. Ann Rheum Dis 2007;66(4):433–439.
Guh DP, et al. BMC Public Health 2009;9:88.
Dong C, et al. Int J Obes Relat Metab Disord 2004;28(6):790–795.
Wright SM & Aronne LJ. Abdom Imaging 2012;37(5):730–732.
Gonzalez Jimenez E. Endocrinol Nutr 2013;60(1):17–24.
TimPascoePhoto0135_Teaser.png)
TimPascoePhoto0081_Teaser.png)
TimPascoePhoto0263_Teaser.png)
