Arguments For Calling Obesity A Disease #4: Limited Response To Lifestyle Treatments
Continuing in my miniseries on why obesity (defined here, as excess or abnormal body fat that affects your health) should be considered a disease, is the simple observation that obesity responds less to lifestyle treatments than most people think. Yes, the internet abounds with before and after pictures of people who have “conquered” obesity with diet, exercise, or both, but in reality, long-term success in “lifestyle” management of obesity is rare and far between. Indeed, if the findings from the National Weight Control Registry have taught us anything, it is just how difficult and how much work it takes to lose weight and keep it off. Even in the context of clinical trials conducted in highly motivated volunteers receiving more support than you would ever be able to reasonably provide in clinical practice, average weight loss at 12 – 24 months is often a modest 3-5%. Thus, for the vast majority of people living with obesity, “lifestyle” treatment is simply not effective enough – at least not as a sustainable long-term strategy in real life. While this may seem disappointing to many (especially, to those in the field, who have dedicated their lives to promoting “healthy” lifestyles as the solution to obesity), in reality, this is not very different from the real-life success of “lifestyle” interventions for other “lifestyle” diseases. Thus, while there is no doubt that diet and exercise are important cornerstones for the management of diabetes or hypertension, most practitioners (and patients) will agree, that very few people with these conditions can be managed by lifestyle interventions alone. Indeed, I would put to you that without medications, only a tiny proportion of people living with diabetes, hypertension, or dyslipidemia would be able to “control” these conditions simply by changing their lifestyles. Not because diet and exercise are not effective for these conditions, but because diet and exercise are simply not enough. The same is true for obesity. It is not that diet and exercise are useless – they absolutely remain a cornerstone of treatment. But, by themselves, they are simply not effective enough to control obesity in the vast majority of people who have it. This is because, diet and exercise do not alter the biology that drives and sustains obesity. If anything, diet and exercise work against the body’s biology, which is working hard to defend body weight at all costs. Thus, it is time we accept this reality and recognise… Read More »
Arguments For Calling Obesity A Disease #2: It Is Driven By Biology
Continuing in my miniseries on reasons why obesity should be considered a disease, I turn to the idea that obesity is largely driven by biology (in which I include psychology, which is also ultimately biology). This is something people dealing with mental illness discovered a long time ago – depression is “molecules in your brain” – well, so is obesity! Let me explain. Humans throughout evolutionary history, like all living creatures, were faced with a dilemma, namely to deal with wide variations in food availability over time (feast vs. famine). Biologically, this means that they were driven in times of plenty to take up and store as many calories as they could in preparation for bad times – this is how our ancestors survived to this day. While finding and eating food during times of plenty does not require much work or motivation, finding food during times of famine requires us to go to almost any length and risks to find food. This risk-taking behaviour is biologically ensured by tightly linking food intake to the hedonic reward system, which provides the strong intrinsic motivator to put in the work required to find foods and consume them beyond our immediate needs. Indeed, it is this link between food and pleasure that explains why we would go to such lengths to further enhance the reward from food by converting raw ingredients into often complex dishes involving hours of toiling in the kitchen. Human culinary creativity knows no limits – all in the service of enhancing pleasure. Thus, our bodies are perfectly geared towards these activities. When we don’t eat, a complex and powerful neurohormonal response takes over (aka hunger), till the urge becomes overwhelming and forces us to still our appetites by seeking, preparing and consuming foods – the hungrier we get, the more we seek and prepare foods to deliver even greater hedonic reward (fat, sugar, salt, spices). The tight biological link between eating and the reward system also explains why we so often eat in response to emotions – anxiety, depression, boredom, happiness, fear, loneliness, stress, can all make us eat. But eating is also engrained into our social behaviour (again largely driven by biology) – as we bond to our mothers through food, we bond to others through eating. Thus, eating has been part of virtually every celebration and social gathering for as long as anyone can remember. Food is celebration, bonding, culture, and identity – all… Read More »
Arguments Against Obesity As A Disease #4: Distracts From Obesity Prevention
Continuing in my mini series on the pros and cons of considering obesity a chronic disease, I would like to now discuss the perhaps most illogical argument against recognising obesity as a disease that I often hear, “Calling obesity a disease will reduce our efforts at prevention”. This argument makes virtually no sense at all, as I cannot think of a single “preventable” disease, where calling it a “disease” would have reduced or thwarted prevention efforts. Whether the aim is to prevent heart disease (dietary recommendations, fitness, smoking cessation), cancers (physical activity, healthy diets, smoking cessation, sunlight exposure), infectious diseases (vaccinations, food safety, hand washing, condom use), road accidents (helmets, seat belts, speed limits), in no instance has calling something a “disease” ever stopped us from doing the utmost for prevention (although more can always be done). Rather, if you truly embrace the concept that obesity, once established, becomes a life-long problem for which we have no cure (the very definition of “chronic disease”), we should be doubling or even quadrupling our efforts at prevention. After all, who would want to be stuck with a chronic disease, if it can indeed be prevented? Governments, NGOs and individuals should be even more enthusiastic about preventing a “real” disease than simply modifying a “risk factor” (which sounds a lot less threatening). Indeed, if I was working in population health, I’d be all for emphasizing just how terrible and devastating the disease of obesity actually is – all the more reason to double down on efforts to do what it takes to prevent it. In fact, considering obesity a “real disease” would put all the folks working hard to prevent obesity right up there on par with those working to prevent “real” diseases like cancer, HIV/AIDS, or Alzheimer’s disease. Thus, the argument that calling obesity a “disease” would somehow distract from efforts to prevent it makes absolutely no sense at all. @DrSharma New Orleans, LA
Arguments Against Obesity As A Disease #2: Inconsistent Relationship Between Body Fat And Health
Yesterday, in my brief series on the pros and cons of calling obesity a chronic disease, I addressed the issue of BMI as a poor definition of obesity (understood here as “abnormal or excess body fat that affects health”). Another common argument I hear from those who do not support the notion of obesity as a chronic disease, is that there is an inconsistent relationship between body fat and health. This is no doubt the case. Indeed, whether or not your body fat affects your health depends on a range of factors – from your genetic predisposition to certain “complications” to the “nature” of your body fat, factors that cannot be captured or assessed by simply stepping on a scale. Often, this variability in the relationship between excess body fat and its impact on health, is used to argue against a “causal relationship” between the two. This argument is often presented along the lines of, “If obesity is a disease, how come I don’t have diabetes?”. Where the direct impact of excess body fat on health should be evident, is when the amount of excess fat poses a direct “mechanical” problem that impedes physical functioning. This impact, however, is likely to vary from one person to the next. A good example of this, is obstructive sleep apnea, where an increase in pharyngeal fat deposition is directly and causally related to the airway obstruction. The causal relationship of pharyngeal fat and the symptoms is directly evident by improvement in symptoms following surgical removal of the excess fat (an operation that is seldom undertaken due to possible complications and redeposition of fat). There is also substantial evidence that significant weight loss (such as induced by bariatric surgery) results in a dramatic improvement in apnea/hypopnea index and sometimes even in complete resolution of the problem. Yet, not everyone with excess weight develops obstructive sleep apnea. One of the factors that explains this variation, is the anatomical dimension of the pharyngeal space, which varies significantly from one person to the next. So, just how much excess fat in the neck region results in symptoms (if any) will necessarily be highly variable. This is not an argument against the relationship between excess body fat and obstructive sleep apnea, it is just the expected variation between individuals that is evident in many diseases. Likewise, when the amount of excess fat impairs the body’s capacity to perform essential functions (from mobility… Read More »
Stretching The Rubber Band
I remember as a kid having a pair of pyjamas that were held up by an elastic rubber band. It must have been a pretty cheap rubber band, because every few months it would wear out and lose its stretch, so it had to be replaced it with a new band. Unfortunately, this is not what can be said about the rubber band that I used in my recent TEDx talk to demonstrate what happens when you try to lose weight. Unlike the cheap band in my pyjamas, the rubber band I used to represent our physiology trying to gain the weight back, never seems to lose its stretch. No matter how hard or how long we pull, the rubber band keeps wanting to bring our weight back to where we started. Yes, perhaps for some people, eventually the rubber band may relax (these would certainly be the exceptions) or may be the “muscles” that we use to pull on the band just grow stronger, which makes it seem easier to keep up the pull – but for all we know, in most people, this “rubber band” is of pretty good quality and seems to last forever. So, how do we take the tension out of the rubber band ? Well, we do know that people who have bariatric surgery have a much better chance of keeping the weight off in the long-term and we now understand that this has little to do with the “restriction” or the “malabsorbtion” resulting from these procedures but rather from the profound effect that this surgery has on the physiology of weight regain. Thus, we know that many of the hormonal and neurological changes that happen with bariatric surgery, seem to inhibit the body’s ability to defend its weight and perhaps even appears to trick the body into thinking that its weight is higher than it actually is. In other words, bariatric surgery helps maintain long-term weight loss by reducing the tension in the rubber band, thus making it far easier for patients to maintain the “pull”. And that is exactly how we think some of the anti-obesity medications may be working. For example, daily injections of liraglutide, a GLP-1 analogue approved for obesity treatment, appears to decrease the body’s ability to counteract weight loss by reducing hunger and increasing satiety, thus taking some of the tension out of that band. Think of it as sprinkling “magic dust” on that rubber band to reduce the… Read More »
Watch Dr. Sharma in the News!
Listen to Dr. Sharma!
