Obesity is one of the foremost challenges in medicine, yet its prevalence has continued to skyrocket since 1960. The accumulation of excess body fat has dramatically increased from 13% to 42% from 1960 to 2021 in the United States. Although we may be healthier than our southern neighbors, Canadians still struggle with this problem, having recorded a substantial 26.8% obesity rate as of 2018.
Obesity is a slippery slope, accompanied by impairments in metabolic, physical, and mental health that continue to amplify the further you slide down the slope. As individuals put on excess fat, a cascade of metabolic effects, – including insulin resistance, hormonal imbalances associated with hunger and satiety signaling, hypertension and cardiovascular impairment, and gradual decreases in physical mobility – can all have a snowball effect that is very difficult to slow down or reverse.
For the majority of our time on earth, humans have commonly lived with low food abundance. During these periods, we developed biochemical adaptations to conserve energy in times of starvation. However, times have changed, food is essentially unlimited in many parts of the world, and past adaptations are becoming maladaptive. These guardrails that were initially put in place to protect us from starvation and allow us to retain some necessary fat are now making it more challenging to achieve our fat loss goals.
Based on CDC guidelines, obesity can be broken down into different classes: Class I is a BMI of 30-35, Class II is a BMI of 35-40, and Class III is a BMI of 40 or higher. Unfortunately, BMI is a crude metric as it can be skewed by high levels of muscle mass and can often hide the more complicated body composition changes that occur during weight loss. Using newer technologies, we can look beneath the skin’s surface at aspects of physiology that tell a much greater story. While many of us spend a lot of time and effort to keep our body fat percentage (subcutaneous fat) at a minimum, a more valuable metric to focus on is the fat between our organs, also known as visceral adipose tissue (VAT). Excess VAT produces harmful inflammatory cytokines around organs, which can promote chronic inflammation and increase the risk for disease. For example, VAT accumulation around the liver can build over time leading to the development of non-alcoholic fatty liver disease (NAFLD), the leading cause of liver transplants today.
Although it is much easier to gain weight than lose weight, it can be even more difficult to keep that weight off once you’ve lost it. Many individuals often experience a rebound effect after significant weight loss, during which they will regain some, if not most, of the weight they had previously lost. To combat this response, it is especially important to take a moderate approach to diet and exercise in the first place. Focus on sustainable diet and exercise practices that can be maintained even after the weight loss goal is achieved to ensure that the weight is kept off for the long term. Increasing protein consumption can be helpful during these periods as protein is highly satiating and will help you build muscle, which can further improve your metabolic rate and help keep fat off your body.
Fortunately, up-and-coming research in the field of obesity has revealed some novel methods to more effectively achieve fat loss and combat obesity. A major discovery in the field of obesity medicine is the use of GLP-1 agonists, a powerful pharmaceutical tool that helps increase insulin secretion and works to reverse the effects of insulin resistance that often accompany obesity. GLP-1 agonists mimic the hormone GLP-1 in our bodies, a molecule that plays an important role in glucose metabolism, insulin sensitivity, and gastric clearance. GLP-1 agonists slow the rate of gastric clearance, meaning that food stays in your stomach longer, giving a greater sense of satiety and helping combat hunger sensations.
It is important to remember that our bodies can always adapt back towards a healthier state of food consumption and exercise if we consistently maintain good practices. It will be challenging, and there will be times when the progress may seem slow or non-existent, but consistent exercise and diet control are key aspects of reversing metabolic dysfunction and ultimately achieving your weight loss goal.
Dr. Rohan Bissoondath,