1.4 Physical Inactivity & Obesity
Physical inactivity and obesity are among the most significant global health challenges. While they are closely linked, they are distinct issues that together contribute to rising rates of chronic disease, disability, and premature death.
Beyond the personal health consequences, these issues place a huge financial burden on health care systems, especially in countries like Canada that have publicly funded health care. In these systems, taxpayers ultimately cover the cost of treating preventable conditions related to inactivity and obesity, such as heart disease, diabetes, certain cancers, and mobility problems.
Physical Inactivity
Physical inactivity refers to a level of activity that is insufficient to meet current physical activity recommendations. The World Health Organization (WHO, n.d.) defines physical inactivity as engaging in less than:
Key Statistics:
- Globally, 33.8% of women and 28.7% of men are physically inactive (WHO, 2024).
- In the Americas, inactivity rates are even higher, with 40.6% of women and 30.5% of men not meeting guidelines (PAHO, 2024).
Obesity
A medical condition characterized by excess body fat that may impair health. It is commonly measured using BMI:
Image Description
The diagram is a pyramid chart illustrating Body Mass Index (BMI) categories, arranged from the lowest to the highest BMI values. The pyramid is divided into seven horizontal sections, with each section representing a different BMI classification. From top to bottom, the sections are:
- Underweight – BMI less than 18.5 kg/m² (smallest section at the top)
- Normal Weight – BMI between 18.5 and 24.9 kg/m²
- Overweight – BMI between 25 and 29.9 kg/m²
- Class I Obesity – BMI between 30 and 34.9 kg/m²
- Class II Obesity – BMI between 35 and 39.9 kg/m²
- Class III Obesity (Severe or Morbid Obesity) – BMI 40 kg/m² or higher (widest section at the bottom)
Key Statistics:
- According to the Financial Times (O’Hare, 2024), adult obesity has more than doubled since 1990:
- Men: from 4.8% to 14.0%
- Women: from 8.8% to 18.5%
- Over 1 billion people worldwide are now living with obesity (The Sun, 2024)
What is your Body Mass Index (BMI)?
You can calculate your own BMI by using this online BMI Calculator provided by Diabetes Canada. (Note: BMI is a quick screening tool but does not directly measure body fat percentage or distinguish between muscle and fat mass.)
Physical Inactivity vs. Obesity
| Aspect | Physical Inactivity | Obesity |
|---|---|---|
| Definition | Not meeting recommended activity levels | Excess body fat that impairs health (BMI ≥ 30 kg/m²) |
| Cause or Outcome? | Often, a contributing factor to obesity | It can be a result of inactivity, but it can also be influenced by diet, genetics, etc. |
| Health Risks | Increased risk of heart disease, diabetes, and poor mental health | Increased risk of heart disease, diabetes, cancer, and mobility issues |
| Modifiable? | Yes, through increased activity | Yes, through physical activity, diet, and medical interventions |
| Independent Risks? | Yes, even active people can experience health risks if sedentary for long periods. | Yes, obesity increases health risks regardless of activity level. |
Causes of Physical Inactivity and Obesity
Shared Causes:
- Sedentary lifestyles (desk jobs, screen time)
- Urban environments limit active transportation
- Reduced access to recreational spaces
- Increased reliance on cars
- Poor health literacy
Obesity-Specific Causes:
- Excess calorie consumption
- Poor diet (high in processed foods, sugars)
- Metabolic or genetic predispositions
- Hormonal factors
- Psychological factors (stress, emotional eating)
