Spitballs Taking Flight in the Guise of Theories

Beware these words: I have a theory. Science defines theories as:

Coherent groups of propositions formulated to explain a group of facts or phenomena in the natural world and repeatedly confirmed through experiment or observation.

Writing in the New York Times, Stephen Kearse tells us that our present age of truth decay is distorting the meaning of a theory. He says that routine conversations are disconnecting theories from facts and reason:

Without shared evidence or explicit reasoning, a theory is just a befuddling spectacle — spitballs taking flight.

This should not be surprising. After all, the word literally doesn’t necesarily mean that something is literally true anymore. As a matter of fact (yes, facts still count), every major dictionary now says that literally can mean figuratively. Of course, it can also mean exactly. But you can’t count on it.

A Few “Theories” to Ponder

Speculation is not the same thing as a scientific theory. Nonetheless, we see quite a bit of speculation that readily flies in obesity and health, as if it were a scientific theory. Too often, it’s unencumbered by pesky data. Promoting fruits and veggies will surely work to prevent obesity. Taxing sugar-sweetened beverages will help us turn obesity trends around. Teaching kids to cook, garden, and appreciate good nutrition will surely put a dent in childhood obesity. Promoting physical activity at school will help, too.

Now, all of those things will probably work to improve health. Fruits and veggies are good for all of us and we don’t get enough of them. Many people get too much of those SSBs and taxing them will likely drive down consumption. Knowledge of cooking, gardening, and nutrition will have lifelong value. And finally, the health benefits of physical activity are undeniable.

Put all of these things together and it’s reasonable to think that population health will improve. Unfortunately, though, we have no evidence that obesity prevalence goes down as a result. In fact, public health policy has been pushing these ideas for some time now and the trends are not cooperating.

So it’s reasonable to ask, are we testing out scientific theories here? Or are we just hurling spitballs?

For further perspective on the need for rigor in obesity policy formulation, click here. For perspective on rigor in nutrition research, click here.

White Sox Pitcher Ed Walsh (made the spitball famous), photograph by Paul Thompson / Wikimedia

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December 29, 2018