Do You Know Your Calories?
As I have blogged before, obesity is the physical manifestation of positive caloric balance and trying to manage your (or your clients’) weight without understanding (or teaching your clients) calories is like trying to balance your bank account without understanding money. Just imagine wanting to balance your bank account without any concept of how much money you make, what the bank charges to handle your money, and how much money you spend each month. Similarly, trying to manage your “calorie account” without any idea of how many calories you are eating (or drinking) in relationship to how many calories your body actually needs is probably not the smartest way to go about managing your weight. So do people with excess weight understand calories and do they have realistic perception of the caloric deficit required to achieve their weight-loss targets? This question was addressed by Gregory Kline and Sue Pedersen from the University of Calgary, in a paper published in Diabetes Obesity and Metabolism earlier this year. In this study, 130 subjects with type 2 diabetes participating in a weight loss trial were asked how much weight they would like to lose and to estimate the caloric deficit required to achieve this weight loss. Notably, all subjects had previously received dietary teaching from a dietitian and a nurse at a diabetes education center. While the desired weight loss ranged from 4.5 to 73 kg (average 26.6 kg), only 30% of participants were willing to estimate the caloric deficit required to lose their target weight. Among participants, who dared estimate the caloric deficit required to lose one kilogram, answers ranged from 0.7 to 2,000,000 calories/kg (median 86 calories/kg). Nearly half the subjects (47%) underestimated the total required caloric deficit to achieve their target weight loss by more than 100,000 calories! Thus, as the authors note, “Despite attendance at a diabetes education centre, this population of obese individuals had a poor understanding of the quantitative relationship between caloric deficit and weight loss.“ My guess is that many health professionals, who recommend weight loss to their clients, are probably not much better at estimating total caloric deficits than the participants in this study. I would imagine that few of the health professionals, who nonchalantly recommend that a patient go lose 50 lbs (e.g. before hip surgery), actually realise that they are prescribing a 175,000 calorie deficit (or almost the total number of calories that… Read More »
Plus and Minus of Teaching Obesity Genetics
One of the suggested ways to address weight-bias and discrimination amongst health professionals could be to teach medical students more about the genetic determinants of excess weight. But will this really reduce weight bias? This question was now addressed by Persky and Eccleston from the US National Institutes of Health in a study just published in the Annals of Behavioral Medicine. One hundred and ten third and fourth year medical students were first randomly assigned to read about genetic or behavioral mechanisms of obesity, or a control topic. Students were then asked to interact with an obese virtual patient in a virtual clinic. While the group of students that had to read up on genetic determinants of obesity showed less negative stereotyping of the virtual patient, they were unfortunately also less likely to recommend weight loss, exercise or dietary consultations. Thus, the authors caution, that highlighting genetic contributions to obesity may lead to both positive and negative outcomes. Clearly, while reducing negative stereotyping may be a worthwhile goal, students also clearly need to understand that despite strong genetic influences, obesity is a multifactorial condition that can be modified by lifestyle modification and other treatments. Or, as the authors point out, “Communication about the genetics of obesity should discuss the multi-factorial and non-deterministic nature of genetic risk“. AMS Edmonton, Alberta Persky S, & Eccleston CP (2010). Impact of Genetic Causal Information on Medical Students’ Clinical Encounters with an Obese Virtual Patient: Health Promotion and Social Stigma. Annals of behavioral medicine : a publication of the Society of Behavioral Medicine PMID: 21136226
Does Weight Discrimination Affect Glucose Control?
Regular readers will recall previous posts on the very real negative health impacts of the weight-bias and discrimination that people with excess weight face everyday. Now, a paper by Vera Tsenkova and colleagues from the University of Wisconsin-Madison, just published in the Annals of Behavioral Medicine, suggests that perceived weight discrimination may directly affect glycemic control. The study included over 900 non-diabetic participants of the Midlife in the United States (MIDUS II) survey and found a clear relationship between measures of adiposity (BMI, waist circumference) and HbA1c levels (a marker of glycemic control). Participants were also asked “how often on a day-to-day basis do you experience each of the following types of discrimination?”: (1) “you are treated with less courtesy than other people”, (2) “you are treated with less respect than other people”, (3) “you receive poorer service than other people at restaurants or stores”, (4) “people act as if they think you are not smart”, (5) “people act as if they are afraid of you”, (6) “people act as if they think you are dishonest”, (7) “people act as if they think you are not as good as they are”, (8) “you are called names or insulted”, (9) “you are threatened or harassed.” Respondents who indicated that they had ever experienced any such mistreatment were then asked “what was the main reason for the discrimination you experienced?” A dichotomous indicator was created based on whether one had ever (at least once) experienced due to weight or height. Interestingly, the highest HbA1c levels were seen in people with high waist circumference levels who also reported having experienced weight discrimination. These negative effects of weight discrimination appeared independent of health behaviors, such as smoking, exercise, and fast-food consumption. As the authors discuss, “Previous studies have documented that obese individuals might not seek timely healthcare or comply with proper healthcare regimens due to fear of mistreatment, teasing, and the demoralization that results from this mistreatment. Thus, perceptions of persistent mistreatment may exacerbate the already harmful consequences of central adiposity for a range of physical outcomes, including glycemic control.“ In addition there may be physiological mechanisms that may account for this relationship. Thus, chronic psychosocial stress such as perceived discrimination might introduce the major stress hormones (norepinephrine, epinephrine, and cortisol), which may have adverse effects on lipid and glucose metabolism. As the authors note, “Understanding how biological and psychosocial factors interact to increase… Read More »
Is There Value in Obesity Management?
This week, the New England Journal of Medicine published an extensive perspective on the value in health care by Harvard Business School’s Michael Porter. The article is of particular interest as we call on health professionals and health systems to provide more more weight management services for clients with excess weight. Although an overwhelming body of evidence supports the impact of excess weight on a health conditions ranging from diabetes to heart attacks, sleep apnea to osteorarthritis, and infertility to cancer, health systems are still spending virtually no money on managing obesity itself – rather, they appear addicted to pouring ever increasing amounts of money and resources into treating its complications. While the taxpayers I speak to are not generally opposed to supporting the Canadian public health care system, they do appear increasingly interested in whether or not the money spent actually provides the best value. As outlined by Porter, “Achieving high value for patients must become the overarching goal of health care delivery, with value defined as the health outcomes achieved per dollar spent….system. If value improves, patients, payers, providers, and suppliers can all benefit while the economic sustainability of the health care system increases.” Porter furthermore emphasises that “value” should always be defined around the customer and should be measured by outcomes achieved rather than by volumes delivered. In addition it is important to note that, “To reduce cost, the best approach is often to spend more on some services to reduce the need for others.” This later statement is of course well documented for obesity interventions both in terms of preventing complications in high-risk individuals as well as in terms of the tremendous savings seen with bariatric surgery in severely obese individuals. Thus, while even modest weight loss of only 5% can reduce the risk for type 2 diabetes by 60%, bariatric surgery for someone with diabetes virtually pays for itself in health cost savings within 2-3 years. There is therefore little doubt that obesity treatments can provide substantial value for money. However, is this value perceived by the recipients and payers? Anecdotally, the “thank you” notes and accolades we regularly receive from our patients certainly support the notion that our services are highly “valued” – but is this enough to convince decision makers that these are dollars well spent? One of the key determinants of “value” according to Porter is the sustainability of the health improvements… Read More »
Weekend Roundup, December 10, 2010
As not everyone may have a chance during the week to read every post, here’s a roundup of last week’s posts in order of popularity: Obesity Management: Handguns versus Slingshots Developing a Research Agenda for Bariatric Care Supersizing Health Care FDA Panel not Contra Contrave Mapping Chronic Disease in Canada Have a great Sunday! (or what’s left of it) AMS Edmonton, Alberta You can now also follow me and post your comments on Facebook
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