Should Public Health Focus on Calories In?Friday, December 14, 2012
To many, obesity is simply a matter of calories in and calories out – they call on the laws of physics, forgetting that living organisms follow the laws of physiology (which I have referred to as “biology messing with physics”).
Thus, while on paper, a solution to eating an extra 100 calories could easily be countered by simply expending those extra calories in exercise, in real life this simply does not work.
Firstly, as argued before, the simplistic reasoning that a few extra calories a day can account for pounds of annual weight gain are simply wrong. It does in fact take consistent and long-term daily excess caloric intake in the order of several 100 extra calories a day to sustain progressive weight gain (see here for a more detailed discussion of this point). Expecting anyone to compensate for a daily excess of 100s of calories through volitional activity is bound to fail.
Furthermore, as also argued before, much of the benefit of regular physical activity on weight loss is probably mediated through its effect on energy intake – thus physical activity is far more related to energy in than energy out.
But this is not what this post is about.
Rather, in a paper just published in BMC Public Health, Jacob Shelley (winner of a Canadian Obesity Network Student award) from the University of Toronto, argues that public health messaging with regard to the obesity epidemic should be reframed as policies to address caloric overconsumption.
As he states:
“A policy cacophony exists when different policy solutions have been developed to address a single issue, and then must compete with one another for support, funding, and implementation. With competing theories about the root causes of obesity, and many plausible although limited solutions being proffered, the resulting “noise” renders it nearly impossible to determine what policies would be most effective. Consequently, as policymakers call for stronger evidence, the evidence continues to support competing policy options, leaving policymakers unsure of which policies to implement. More evidence may simply exacerbate the obesity policy cacophony, especially given the difficulty of translating evidence into policy.”
“This paper argues that to address the policy cacophony it is necessary to rethink the problem of obesity, and more specifically, how the problem of obesity is framed. This paper argues that the frame “obesity” be replaced by the frame “caloric overconsumption”, concluding that the frame caloric overconsumption can overcome the obesity policy cacophony.”
Shelley puts forward two key arguments to support reframing the obesity discussion as caloric overconsumption:
“As a frame, “obesity” does not identify any specific causes – and obesity certainly is not the cause of itself! Thus the frame obesity remains open to be interpreted and influenced by competing theories about what does cause obesity. This makes it difficult to identify or assess potential policies or interventions. The second rationale stems from the potential benefits of using the proposed frame, caloric overconsumption. The frame caloric overconsumption minimizes some of the framing competition by identifying a specific cause of obesity, energy input. Moreover, the frame caloric overconsumption will permit a more critical analysis of the various policies and interventions that can be used in obesity prevention.”
As to why focus on energy in rather than energy out, Shelley has the following to offer:
“However, research is increasingly demonstrating that energy output actually plays a very small role in obesity. Recent estimates suggest that 60% to 100% of obesity amongst Canadians is related to excess calorie consumption, and not inadequate energy expenditure. In fact, exercise and physical activity has been shown to play a limited – and sometimes counterproductive – role in weight control….This is not to suggest that exercise or physical activity is not important. It certainly is, and for a variety of reasons, including physical and mental health. But as a strategy for obesity prevention (or treatment), the evidence does not support physical activity as a promising solution, particularly at a population level. The proposed frame, caloric overconsumption, has the potential to change the policy environment by focusing on a specific cause of obesity, energy input.”
But Shelley is not naive enough to think that such a reframing of obesity as an energy-in problem will be easy:
“The greatest challenge, however, will come from the food and beverage industry. Even if policymakers are willing to address caloric overconsumption, they will continue to face the power of food and beverage industry. At present, the industry has been opposed to most, if not all, food policies that would bring about meaningful changes in obesity rates….Any reframing that places more responsibility on industry is likely to be met with considerable opposition. Industry can also be expected to emphasize the personal responsibility on the part of those that do overconsume…. As frames do not require evidence, industry can dominate framing competitions by manufacturing uncertainty, a tactic perfected by tobacco companies.”
This brings us full circle to where the food and beverage industry needs to fit into the discussion.
As noted before, to become part of the solution, food and beverage companies have to step up to the plate and fully acknowledge that obesity is a problem of calories in, for which they bear a considerable part of the responsibility.
This step of acknowleding their responsibility, however, has to be followed by real efforts to find and provide solutions.
Putting calories on packages is one thing – changing consumer practice by also ensuring that consumers know what those numbers actually mean is a whole different story.
Discovering how to stay profitable (or make even more money) while selling fewer calories, I believe, is the Holy Grail that food and beverage companies will have to solve.
But it is not only up to food companies to solve this problem.
For food companies to remain profitable while selling fewer calories, policy makers will need to change (or level) the playing field and consumers will need to be willing to pay more for less (fewer calories).
Nevertheless, as Shelley points out,
“…reframing holds considerable potential to shift the policy environment, particularly if public health advocates strategically present the frame of caloric overconsumption as a logical and foreseeable outcome of toxic food environments. Importantly, reframing will allow for policymakers to more readily decipher the current policy cacophony by identifying policies that will address energy input….Aimed at caloric overconsumption rather than obesity, these policies promise to be more effective. Effectiveness would not be measured by reductions in obesity rates, which may take years to develop (and is a point on which many current obesity prevention policies fail), but by more proximal (and temporally closer) outcomes, such as reductions in calories consumed or diet quality.”
Shelley JJ (2012). Addressing the policy cacophony does not require more evidence: an argument for reframing obesity as caloric overconsumption. BMC public health, 12 (1) PMID: 23199375