There’s been a lot of discussion in the news regarding the onslaught of American obesity, and the potential health risks attributable to a variety of different causes. Obesity is a comorbidity and has a profound impact on the risk of workplace injury, the delivery of appropriate remedial care, and the amelioration of the effects, following injury or accident.
And one recent post, I noted the extent to which obesity and or diet may contribute to the likelihood of cancer. See Disparity and Evolution (August 2024). In another recent post, I noted the distinction between causation and coincidence. Challenges with causation are deeply ingrained in many states' conceptualization of workers' compensation.
A new story regarding the content of foods is interesting from multiple perspectives. The British Broadcasting Corporation (BBC) reports that some experts have concluded that it is highly impractical, and may prove impossible, to determine exactly what the impacts are of various components of the American diet.
They note that we face a variety of additives and ingredients, and they express doubt that these can be each individually studied in a sufficiently controlled and significant manner such that the health impacts of each could be isolated, analyzed, and evaluated. The challenge is with variables, and in case you don't remember from high school, the more variables in the equation the more difficult it becomes.
For example, in the equation 4 + x = 6, even I can cipher out that "x" has to be 2 (if it is not, show your work when explaining why). There is only one variable. So that one element, "x," can be teased out, identified, and solved. But, 10x+4y = 3 is more difficult. First, the impact of two variables has to be considered. And, the values assigned to each is codependent on the value of the other. In fact, there is a population of values for both "x" and "y," each of which is potentially correct.
The challenge is thus illustrated, but even with the large group of numbers that could satisfy "x" and "y," this does not begin to parallel the challenge of food additives. There are a multitude of chemicals being added to foods for the purpose of enhancement. Some are for taste, others for texture, others for preservation, and so on.
Each of those additives may have the intended effect and yet also some potential unintended effect on our bodies. That result is reasonably easy to comprehend. But, how does that one chemical react to or interact with a second chemical in the same product? That reaches a bit deeper into the complexity, the two-variable equation. Next time you pick up a product, read the list of ingredients and you may appreciate the complexity of many variables.
The scientists involved with the BBC article explain that there is some hope of identifying the impacts of any particular substance. They isolate that substance and expose us to it. Reactions and outcomes are measured, recorded, and reduced to data. Across large data sets, reactions and outcomes can be predicted for people generally, though individual reactions might still vary.
The discussion made me think of the differential diagnosis, a process in which a medical expert arrives at a working hypothesis, and then through a series of evaluating tools, or testing, attempts to eliminate or establish indicia that support the hypothesis. So, when the complaint is knee pain, the doctor strives to identify the portion of the knee that is damaged and then assess the nature and extent of that damage. In this process, the physician is teasing out variables, and assessing what each may or may not represent.
The challenge has perhaps existed since we began eating foods that have been processed. The idea of food additives is not novel. The challenge being discussed, however, is "So-called ultra-processed foods (UPF)," and our diets are increasingly focused on them. The article's authors assure us that such foods now "account for 56% of calories consumed" in general, and they are more prominent in economically challenged communities.
In these UPF, the most recognizable ingredients may be the "fat, sugar or salt" that are predominant. The foods are perhaps convenient, long-lasting, and appealing. What they also are is complex in terms of how their contents may impact us. In that debate, various experts express opinions about the value of variables, but it is possible there are multiple solutions to the equation. There are actions and interactions.
However, there is apparently some room for disagreement about what foods are in the UPF category. Some are studying simply the definition. Thus, while there is trepidation about these products and our consumption habits, definition, and comprehension might hinder even the most dedicated consumer. The best definition offered is: "Generally, they include more than five ingredients, few of which you would find in a typical kitchen cupboard."
The second complication is ongoing debate as to whether UPFs are demonstrably unhealthy or problematic. In order to point to such a conclusion, one faces the challenge of the equation discussion above. If a particular food is or is not a UPF challenges study, and then the isolation of that particular UPF provides only more complication.
The end result seems to be that UPFs may be "linked to" things like "cancers, heart disease, obesity, and depression." Those who eat large quantities of these foods have "a roughly 10% greater chance of dying early." That is a troubling solution to the equation. But which UPF, which ingredient or combination, is a more challenging question. And, one cannot ignore the "large quantities." What volume of UPFs is not indicative of an increased risk?
The analysis that could answer such questions is elusive. The results of eating these foods, the resulting "health problems would be extremely complex." And because that equation has so many variables, there are distinct challenges in isolating and studying any particular one variable, that is one UPF or ingredient.
The experts suggest this would require studies in which people were in very carefully controlled groups. The people would have to start with reasonably similar eating habits. Their food intake would have to be measured, and "matched exactly for calorie and macronutrient content." The study would have to, effectively, remove all other variables so that only "x," the UPFs remained as a variable.
In short, a study of that complexity and specificity is perhaps beyond our capacity, or at least our economy. The experts concede that such an approach "would be expensive research," and there are limited resources from which funding might come. One expert contends that anyone providing such funding would potentially be "motivated to run these kinds of trials" by a preconceived notion of "what they want the conclusions to be."
This admission by the experts should caution us all when there is discussion of "causation."