Chapter 11. Weight Management
Introduction to Weight Management
Learning Objectives
By the end of this chapter you will be able to:
- Describe the process of calculating Body Mass Index (BMI)
- Describe factors that contribute to weight management
- Identify evidence-based nutritional recommendations
- Identify principles of Health at Every Size
“Obesogenic” is a word that has sprung up in the language of public health professionals in the last two decades. The Centers for Disease Control and Prevention (CDC) defines obesogenic as “an environment that promotes increased food intake, non-healthful foods, and physical inactivity.”[1]
According to Statistics Canada data on body mass index (BMI) of Canadians, 27% and 34% of Canadians were obese and overweight, respectively in 2017.[2] BMI is used to define obesity, but has limitations, which is explained further in this chapter. Overall Canadian obesity rates have remained relatively high, but stable over the past decade. [3] However, there are significant regional differences across Canada in obesity rates, with BC having the lowest regional obesity rate at 22% of British Columbians.
Numerous obesogenic agents that contribute to this public health problem have become a part of everyday life in Canadian society. The fast food industry has been growing for decades and continues to grow despite the latest economic slump. In America today there are over twelve thousand McDonald’s restaurants, while in 1960 there was one. Food portions have been getting bigger since the 1960s, and in the 1990s North American society experienced the “super-size” marketing boom, which still endures. Between 1960 and 2000 more than 123 million vehicles were added to the American society. Escalators, elevators, and horizontal walkways now dominate shopping malls and office buildings, factory work has become increasingly mechanized and robotized, the typical American watches more than four hours of television daily, and in many work places the only tools required to conduct work are a chair and a computer. The list of all the societal obesogenic factors goes on and on. They are the result of modernization, industrialization, and urbanization continuing on without individuals, public health officials, or government adequately addressing the concurrent rise in overweight and obesity.
With obesity at epidemic proportions in Canada it is paramount that policies be implemented or reinforced at all levels of society, and include education, agriculture, industry, urban planning, healthcare, and government. Reversing and stopping obesity are two different things. The former will require much more societal and individual change than the latter. The following are some ideas for constructing an environment in America that promotes health and confronts the obesity epidemic:
Individual Level
- Purchase less prepared foods and eat more whole foods.
- Decrease portion sizes when eating or serving food.
- Eat out less, and when you do eat out choose low-calorie options.
- Walk or bike to work. If this is not feasible, walk while you are at work.
- Take the stairs when you come upon them or better yet, seek them out.
- Walk your neighborhood and know your surroundings. This benefits both health and safety.
- Watch less television.
Community Level
- Request that your college/workplace provides more access to healthy low-cost foods.
- Support changes in school lunch programs.
- Participate in cleaning up local green spaces and then enjoy them during your leisure time.
- Patronize local farms and fruit-and-vegetable stands.
- Talk to your grocer and ask for better whole-food choices and seafood at a decent price.
- Ask the restaurants you frequently go to, to serve more nutritious food and to accurately display calories of menu items.
National Level
- Support policies that increase the walkability of cities.
- Support national campaigns addressing obesity, such as America on the Move.
- Support policies that support local farmers and the increased access and affordability of healthy food.
It is critical for the nation’s health to change our environment to one that promotes weight loss and/or weight maintenance. However, action is needed on multiple fronts to reverse the obesity epidemic trend within one generation. In this section you will learn how to assess body weight and fatness. You will also learn that it is not only society and environment that play a role in body weight and fatness, but also physiology, genetics, and behavior—and that all of them interact. We will also learn evidence-based solutions to maintain body weight at the individual level.
In the context of weight management, it is important to recognize that healthy eating according to dietary guidelines is relevant for everyone regardless of their weight. Ultimately, it is the health promoting behaviours that are key for reducing risk of disease as opposed to achieving an ideal body size or shape according to societal expectations, which might be attainable through short-term weight loss, but challenging to maintain over the long-term. Studies suggest that an overt focus of weight loss is not only ineffective to promote health and wellbeing, but can also have unintended negative consequences such as disordered eating*, eating disorders*, unhealthy cycling of weight loss and gain known as ‘yo-yo dieting’, neglecting other factors important for health, reduced self-esteem, weight stigmatization and discrimination.[4] These findings are supportive of the principles of ‘Health at Every Size’, which will be introduced at the end of this chapter.
*Although often used interchangeably disordered eating and eating disorders are not the same thing. Eating behaviours occur on a continuum from: “no rules or restrictions followed” –> “somewhat restrictive” –> ”disordered eating” –> “eating disorders”. An eating disorder is a psychiatric illness typically involving extreme body dissatisfaction and long-standing eating patterns that have a detrimental effect on body function. Severe food restriction, obsessive exercising, self-induced vomiting, and laxative abuse are common behaviors of individuals with eating disorders. Anorexia Nervosa and Bulimia Nervosa are the two most commonly diagnosed eating disorders. Disordered eating, on the other hand, is a more general term that describes a variety of abnormal or atypical eating behaviours that people use to obtain or maintain a lower body weight. Examples of these types of behaviours include going on and off diets or restrictive eating such as refusing to eat any high fat foods. Many people unknowingly experience problematic disordered eating and it is important to get help from medical professionals before the problem worsens. Refer to the following resources from the BC Children’s Kelty Mental Health Resource Centre on ‘Disordered Eating‘ and ‘Dangerous Eating Behaviours‘ for further information.
- Obesogenic Environments. Center for Disease Control and Prevention (CDC). https://www.cdc.gov/pcd/issues/2015/14_0559.htm. Published 2013. Accessed September 22, 2017. ↵
- Statistics Canada, 2016 and 2017. Canadian Health Measures Survey. Ottawa. ↵
- Statistics Canada, 2007 to 2009. Canadian Health Measures Survey. Ottawa. ↵
- Bacon L, Aphramor L. Weight science: evaluating the evidence for a paradigm shift. Nutrition journal. 2011 Dec;10(1):9. ↵