Statistics show that more and more Canadians are overweight in every age group, even in children. How do we define obesity, and how can we prevent it?
Definitions, BMI and abdominal obesity
According to the World Health Organization (WHO), overweight and obesity are defined as “abnormal or excessive fat accumulation that presents a risk to health.”
In adults, the Body Mass Index (BMI) is usually used to estimate the health risk associated with a person’s weight. The BMI is calculated using weight and height, placing individuals into one of four categories. Each category (or sub-class) is associated with a health risk, which increases along with the BMI.
|Healthy weight||18.5 – 24.9||Low|
|Overweight||25 – 29.9||Increased|
|class I||30 – 34.9||High|
|class II||35 – 39.9||Very high|
|class III||≥ 40||Extremely high|
Despite being very useful, the BMI is not a perfect tool, since it does not take into account other factors such as race, gender, bone structure, muscle mass and age.
Another important factor is where the fat is accumulated in the body. For example, it has been established that abdominal obesity (i.e. fat accumulated in the abdomen, around the organs) increases the risk of many diseases.
Waist circumference is usually used to evaluate abdominal obesity. In men, a waist circumference greater than 94 cm (37 inches) is typically considered to be a sign of obesity. In women, the measurement is 80 cm (32 inches). The numbers are slightly different in Asian and South American individuals (> 85 or 90 cm in men, respectively, and > 80 or 90 cm in women).
Weight-related health risks
Being overweight, especially when combined with abdominal obesity, increases the risk of developing various health problems. Hypertension, type 2 diabetes and high LDL (bad) cholesterol are common among obese individuals, as are certain respiratory conditions such as sleep apnea.
In addition, excess weight also affects the muscular and skeletal system, since it can cause or aggravate back and joint pain (particularly in the hips and knees, which must support the weight of the body).
Lastly, many studies have found a link between obesity and certain cancers, such as those of the esophagus, pancreas, kidneys, uterus, cervix and prostate.
Humans today no longer eat simply to survive, and food has become closely connected to comfort and celebration. In industrialized countries like Canada, it’s easy to eat for no reason, even when we’re not really hungry, because food is so readily available. We tend to eat or drink to reward or console ourselves.
The body needs the energy supplied by food in order to function normally. The amount of energy we need is directly related to our physical activity level, i.e. people who are very active need more energy (calories) than those who are sedentary. However, it’s easy to eat more calories than we need when we’re inactive. The end result? Our body stores the excess energy as fat.
Tips for achieving a balance
In order to reach and maintain a healthy weight, it’s important to create a balance between physical activity and diet. Here are some tips for people who tend to eat too much or are not physically active enough.
- Eat a bit less at a time, but more often throughout the day (every 2 to 3 hours). This reduces the risk of overeating at a meal because we’re famished.
- Use smaller plates. It’s a simple way of reducing the risk of taking portions that are bigger than we need. The recommended portions are often much smaller than we think (and eat)!
- Avoid eating in front of the television. People who eat in front of the television don’t pay attention to the food they’re eating because they are focussed on the television. As a result, they usually eat much more than necessary.
- Watch out for liquid calories! Juices (even those with no sugar added) and alcoholic beverages are very high in calories.
- Out of sight, off the hips… Without demonizing them or forbidding them entirely, sugary or salty snacks (and other foods with little nutritional value) should not be part of your typical diet.
- Be active on a regular basis for short amounts of time, rather than less often for longer periods. Rather than trying to go to the gym for an hour three times a week, it may be more productive to find ways to move at home. Doing housework can count, if you take advantage of it to sneak in some dance steps as you vacuum!
- Team up! It can be hard to motivate yourself when you’re alone. Having an exercise partner can help (spouse, friend, colleague, child).
- Increase the pace gradually. When you want to do too much too soon, you risk getting discouraged. Slowly but surely is the way to go when increasing your physical activity level.
The best way to maintain a healthy weight is to adopt a lifestyle where there is a balance between the way you eat and your level of physical activity. This new lifestyle must be enjoyable, otherwise you will go back to your old ways!