As of this writing, it is thought in Canada that 59% of people are overweight (OW) and 23% are obese with a body mass index (BMI) greater or equal to 25 or 30 kg/m2 respectively. While BMI is not the only way to assess adiposity, it is the main measure used for assessment in research, management guidelines and as a benchmark for weight loss and maintenance. It may under or over diagnose excessive weight depending on sex, age, ethnicity and those with greater or lower lean body mass. The Edmonton Obesity Staging System is widely recognised; it incorporates additional considerations such as risk factors, functional limits, psychological factors and wellbeing.
Different terminologies have been suggested as alternatives to Obesity such as, excessive weight, unhealthy weight, or affected by weight. Currently the term Obesity is used for medical diagnosis for the purposes of consistency in terminology for research and clinical care, insurance coverage and other factors.
How Excessive Adiposity Affects the Health and Function of the Body.
It is currently recognized that body fat is not simply a storage organ. When excessive, it becomes physiologically active in many unhealthy ways. It can exert harmful effects both through its influence on the body’s metabolism, called “sick fat disease” and the effects of mass on the body the body through the excessive load and dysfunctional forces on body structures such as on the joints or chest wall and airway; “fat mass disease”.
OW and Obesity need to be recognised as chronic diseases. As with other important diseases the condition is heterogeneous in its causes. Nutrition and eating patterns and inadequate activity are often cited as main contributors but as research is discovering genetics, hormones, and the immune and nervous systems play an important role in the genesis and perpetuation of OW and obesity and its consequences.
How Unhealthy Fat Affects Body Function Leading to Poor Health.
Fat is the largest organ in the human body; when the fat mass grows beyond healthy levels the adipose tissue signaling affects the body’s metabolic function leading to further weight gain, insulin resistance, and the development of the important risk factors for the diseases of aging. As such, OW or Obesity is a major risk factor for development of: type 2 diabetes, dyslipidemia (abnormal lipids), high blood pressure, heart disease, common cancers, forms of liver disease and possibly premature death. Not all people with OW or Obesity develop harmful metabolic consequences.
The adipose fat mass effect contributes to Obstructive Sleep Apnea, degenerative joint disease, dysfunctional changes in body alignment and balance, reflux, hernias and numerous skin conditions. Commonly, persons with OW and Obesity suffer from mental health consequences such as poor self esteem, depression and anxiety. The effect on mental health may be neurophysiologic effects in the brain and /or the effects of bias and stigma people may face in workplace, social and/or healthcare settings.
Obesity Should be Treated as Disease State and Cause of Other Important Diseases.
Obesity experts argue that treating OW or Obesity, especially in those with risk factors or downstream disease, is addressing root cause rather than managing each of the consequences as separate, silos or entities. The goal in treating OW and Obesity is harm reduction; that is improving health, quality of life and longevity. Some of the most common health challenges that we face in Canada could be addressed by lowering OW and Obesity prevalence; we need to recognize it as a common denominator in common diseases and offer proven, effective and achievable solutions and support systems to improve health outcomes through weight loss and weight loss maintenance. A 5-10% reduction in weight has been shown to improve both metabolic and fat mass disease severity.
Managing OW and Obesity.
While weight loss is a goal, the harder and more important aspect is sustained weight loss maintenance for improving a person’s current and future health. Improved nutrition and activity with behavioural support remain the mainstays of addressing OW and Obesity. When these measures are insufficient to reach goals such as adequate BMI reduction and improvement in risk factors or disease measures then medical interventions such as approved drug therapies or surgery may be added to the treatment scope for weight loss and for improved heath and quality of life outcomes in the short and longer term.
New developments in medication such as the glucagon-like peptide-1 receptor agonists, GLP-1RA, (semaglutide and liraglutide) have greatly benefited patients with Obesity and Type 2 Diabetes; the conditions for which they were developed and initially approved. There are also other classes of medication available in Canada that influence other pathways involved in certain forms of unhealthy weight. As with medication treatment benefit for other chronic diseases, such as high blood pressure, the drugs effect on adiposity reduction works only while it is being used. Additionally, as in other medical treatment examples, obesity medication does not work in all people to the same extent or may not work at all for some. Ideally, assessment, monitoring and longitudinal care should be provided by an experienced practitioner incorporating a holistic, patient- centered approach. Despite an uptick in influencer promotion and media focus, anti-obesity drugs should be used for the purposes for which they were developed, not in healthy persons without the conditions for which they were designed.