Body Mass Index (BMI) in Canada: Tips for Healthy Living

Body mass index (BMI) is a common tool in Canada for estimating healthy body weight and assessing the risks associated with being overweight or underweight.

Data from Canadian Community Health Survey shows that nearly 1 out of 4 Canadian adults is obese now based on their BMI. 

Being overweight or obese increases the risk of getting stuff like heart disease, diabetes, cancer, and other chronic illnesses by a lot. These illnesses can reduce quality of life and drive up healthcare costs. The good news is that keeping a healthy BMI by improving lifestyle habits can help lower these risks.

This article looks at how BMI is used to evaluate the weight status of Canadians. It also covers some concerning trends happening now. And it suggests practical solutions people and policymakers can use to reverse the obesity epidemic.

What is BMI and how is it calculated?

Body Mass Index (BMI) is a common measurement tool used to assess weight status and associated health risks in adults aged 20 and older. BMI provides a reliable indicator of body fat for most people.

More specifically, it is a mathematical formula calculated as follows:

BMI = Weight (kg) / Height (m)2

For example, an individual weighing 70 kg (154 lbs) and measuring 1.75 meters (5 ft 9 in) in height would have a BMI of 22.9, which falls within the normal range.

While BMI correlates with body fat percentage in most adults, it does not directly quantify body fat. BMI is a screening tool that produces a single number meant to give a general indication of whether a person’s body weight is low, normal, or high relative to their height. It provides a benchmark for comparing weight status within populations.

What are the BMI weight categories for adults?

Standard BMI ranges have been established to categorize weight status in adults aged 20 and over:

Source: What is Body Mass Index (BMI)? – www.news-medical.net

The obesity range can be further subdivided into Class I (BMI 30-34.9), Class II (BMI 35-39.9) and Class III (BMI 40+) obesity, with increasing health risks at higher levels.

Individuals classified as overweight or obese based on their BMI have an elevated risk for developing chronic conditions like heart disease, diabetes, cancer, and osteoarthritis, among others.

Those with a BMI below 18.5 may have nutritional deficiencies, osteoporosis, and also face health risks.

What are the BMI ranges for children and adolescents?

In children and adolescents aged 2-20, BMI is plotted on growth charts specific to age and sex to determine the corresponding BMI-for-age weight status percentile.

The Centers for Disease Control and Prevention (CDC) has established the following BMI categories for youth based on these percentiles:

• Underweight: Below 5th percentile
• Healthy Weight: 5th to 85th percentile
• Overweight: 85th to 95th percentile
• Obese: Above 95th percentile

Source: Child and Teen BMI Categories – cdc.gov

These pediatric charts account for the dynamic changes in height, growth rate, and body composition throughout childhood and puberty. BMI screening and growth monitoring in youth can identify early weight management issues and reduce long-term health risks.

What are the limitations of BMI as a health indicator?

Despite being the most widely adopted proxy measure for indicating body fat and weight categories, BMI does have limitations:

• Does not differentiate between body fat, muscle, bone density, etc. Athletes may have higher BMIs due to increased muscle mass.
• Does not consider fat distribution (abdominal vs peripheral). Abdominal fat increases health risks.
• Less accurate for individuals at weight extremes or with certain medical conditions.
• Does not account for age, gender and ethnic differences in body composition.
• Not adjustable for proportionally shorter or taller individuals.

Due to these constraints, BMI should not be solely relied upon as a diagnostic tool. Rather, it is best utilized as part of a health screening alongside other metrics like waist circumference, cholesterol levels, and blood pressure to evaluate weight-related health risks.

What are the health risks of having a high BMI?

Excess weight classified by a BMI in the overweight or obese ranges places individuals at heightened risk for developing an array of chronic health conditions, disabilities, and psychosocial issues:

• Cardiovascular diseases: Hypertension, coronary artery disease, congestive heart failure, stroke
• Metabolic disorders: Type 2 diabetes, dyslipidemia, fatty liver disease
• Respiratory problems: Obstructive sleep apnea, asthma, pulmonary embolism
• Musculoskeletal diseases: Osteoarthritis, back and joint pain, decreased mobility
• Mental illnesses: Depression, anxiety, eating disorders, low self-esteem
• Cancers: Breast, uterine, colon, kidney, esophageal
• Increased mortality risk: Up to 9 years reduction in life expectancy

This wide range of detrimental health consequences shows the pressing need to address Canada’s high and climbing overweight and obesity rates revealed through BMI screening data.

Given the many health risks linked to having a high body mass index, Canadians seeking life insurance with a high BMI may encounter challenges finding affordable premiums and coverage.

What are the health risks of having a low BMI?

While overweight and obesity are far more prevalent in Canada, a low BMI below 18.5 also poses health concerns of its own.

Underweight individuals may suffer from:

• Malnutrition: Insufficient energy and nutrient intake can arise from poverty, eating disorders, chronic diseases, substance abuse, or mental illness.
• Anemia: Underweight BMI can signify deficiencies in iron, folate, vitamin B12, or other nutrients vital for red blood cell production.
• Osteoporosis: Too little mechanical loading on bones over long periods can precipitate accelerated bone loss and fractures.
• Reproductive issues: Underweight women may experience irregular menstruation, infertility, or complications during pregnancy.
• Weakened immunity: Malnutrition hampers immune defences, raising risks for frequent or severe infections.

Therefore, an underweight BMI can be a vital red flag for underlying medical causes requiring further evaluation and care. It may also necessitate interventions to improve diet, nutrient status, and self-care behaviours in some patients.

Canada’s Overweight and Obesity Trends Based on BMI

Obesity rates vary notably by province across Canada. According to 2017 data, the national average prevalence of obesity among adults was 27%.

Obesity rates vary notably across Canada’s provinces and territories. The table below shows the prevalence of obesity among Canadian adults by province based on 2017 data:

As shown, obesity rates were lowest in British Columbia at 22% and highest in New Brunswick and Newfoundland/Labrador at 38%. The prairie and Atlantic provinces generally had higher obesity prevalence compared to the national average of 27%.

Source: Obesity in Canadian Adults, 2016 and 2017 – Statistics Canada

How is BMI trending among Canadian adults?

Obesity rates in Canada have climbed over the past few decades. The table below shows the obesity prevalence by BMI for Canadian adults in 2003, segmented by age group and gender:

In 2003, 15.9% of Canadian men over 18 were obese, based on a BMI over 30 kg/m2, compared to 13.9% of women. Obesity prevalence increased with age, reaching 19.4% for men and 17.5% for women aged 45-64. This data shows worrying obesity trends among middle-aged adults, especially.

Source: Body mass index (BMI), by age group and sex – www150.statcan.gc.ca

How does Canada’s average BMI compare internationally?

The rise in obesity has impacted countries globally, but BMI levels vary significantly by nation. The table below shows the mean BMI values for selected countries in 2014:

The highest BMIs were seen in Pacific islands like Nauru, while Japan maintained lower BMI. The U.S. and Mexico had a high mean of over 28 among industrialized nations. Canada was above the OECD average of 26.6. Higher mean BMIs indicate greater obesity prevalence over time.

Monitoring BMI globally allows for the identification of high-risk regions and the sharing of best practices. Canada and other countries should act to improve nutrition and physical activity.

Source: List of sovereign states by body mass index – en.wikipedia.org

What strategies and policies address high BMI in Canada?

To counteract Canada’s high and rising BMI statistics, various initiatives have been undertaken by government agencies and public health groups:

• National public health campaigns promote healthy weights through engaging fitness tips and nutrition education.
• Provinces like Ontario, Alberta, and Nova Scotia have expanded access to no-cost or low-cost bariatric care, behavioural weight loss programs, and specialized obesity management clinics that are covered under provincial health plans.
• Proposed federal bills like C-211 aim to impose restrictions on marketing unhealthy foods and beverages to children in order to curb childhood obesity rates.
• Electronic medical records increasingly integrate BMI documentation prompts to standardize obesity screening and monitoring across providers.
• Federal grants fund research on emerging weight management solutions and subsidize programs targeting groups with high BMIs.

Recommendations for BMI Screening in Canada

Canadian clinical practice guidelines provide the following evidence-based recommendations for BMI screening and interpretation in order to guide obesity prevention efforts:

• All adults aged 18 years and older should have their BMI assessed minimally once annually, with increased frequency for those overweight or obese.
• BMI should be interpreted in conjunction with age, gender, ethnicity, and muscle mass, not in isolation.
• For children/youth, BMI should be plotted on CDC BMI-for-age growth charts starting at age 2 years at each pediatric well-child visit.
• BMI screening should occur alongside other health assessments like waist circumference, blood pressure, and cholesterol.
• BMI results should inform individually tailored nutrition, exercise, and lifestyle recommendations to promote healthy weights.

While some limitations exist, routine, standardized BMI screening remains a crucial tool for tracking population health and facilitating timely interventions.

How to Improve Your BMI through Lifestyle Changes?

If your BMI is in the underweight or overweight ranges, you can aim to reach a healthier weight through lifestyle adjustments:

• Consult your doctor for individualized weight loss or weight gain advice
• Increase physical activity to 30-45 minutes per day to expend excess calories if overweight or obese.
• Reduce calorie intake modestly if BMI is high by eating more vegetables, fruits, and whole grains while limiting processed foods, sugar, and unhealthy fats. Aim for a maximum daily deficit of 500 calories for weight loss.
• Gain weight healthfully if underweight by adding nutritious, high-protein and high-calorie foods to your diet under medical guidance.
• See a dietitian to help formulate a personalized nutrition plan for your BMI goals.
• Set realistic weight loss targets up to 2 lbs per week if overweight or 1 lb weekly if obese. More rapid loss may signal muscle wasting.

With time, consistency, and support from your healthcare team, reaching and sustaining a BMI in the normal range is an attainable goal that can optimize your health. Monitor your BMI over time to assess your progress.

Aside from BMI, other common stats like average IQ, average height and weight for men and average height and weight for women also offer insights into overall health and these factors can sometimes play a role in life insurance assessments.

The bottom line

As a Canadian, understanding your BMI can provide helpful insights, but this metric does not define your worth or health. Focus on feeling your best through balanced nutrition, regular activity, and positive lifestyle habits aligned with Canada’s Food Guide and physical activity recommendations.

Stay motivated by monitoring your BMI over time and celebrating healthy improvements. Remember to be kind to yourself throughout the process. If you have concerns about your weight or BMI, reach out to your Canadian healthcare providers for personalized guidance.

Maintaining your BMI in the healthy range is an achievable goal with commitment and support. This number on a scale does not determine your value – your power lies in the paths you take each day to care for your remarkable body.

FAQs related to Body Mass Index in Canada

How is BMI calculated in Canada?

BMI is calculated the same way in Canada as other countries: by dividing a person’s weight in kilograms by their height in meters squared.

What is considered a healthy BMI range in Canada?

In Canada, a BMI between 18.5 and 24.9 is considered healthy for most adults. Those with a BMI of 25-29.9 are considered overweight, while a BMI over 30 indicates obesity.

Where can Canadians find their BMI on medical reports?

Canadians can find their BMI listed on medical reports and lab results under the "Vitals" section, along with their height, weight, and other metrics.

Why do doctors in Canada use BMI to assess health?

BMI is an easy, inexpensive way for Canadian doctors to broadly assess body fat and predict obesity-related health risks like diabetes and heart disease. It is commonly used for population statistics.

Do all doctors in Canada use the same BMI scale?

Yes, all doctors and health professionals in Canada use the standard BMI scale as outlined by Health Canada and the World Health Organization guidelines.

Can BMI be inaccurate for certain groups in Canada?

Yes, BMI can be less accurate for very muscular Canadians, seniors who have lost muscle mass, and some ethnic groups. Doctors may interpret BMI differently for certain individuals.