The Gray Tree

True, False, and Shades of Gray

How are we doing these days on quizzes of true and false? In public affairs, it’s become quite a challenge. In nutrition and obesity science, the challenge is nothing new. Some things are clearly true. Obesity is a highly heritable condition, for one example. Other things are clearly false. For example, to lose one pound does not simply require cutting 3,500 calories. However, many shades of gray lie in between those extremes of black and white. In that zone, we have speculation about what might be true. Or false. But speculation presented as if it were a matter of fact is common, and it’s misleading. In fact, it’s dishonest.

The Role of Speculation and Suppositions

Because we have much to learn about obesity and nutrition, we have much speculation. For example, many people believe that taxing sugar-sweetened beverages will lead to less obesity and better health. It’s clear enough that taxing these beverages will lead to changes in behavior. Multiple studies show this to be true.

But one change in human behavior often leads to other behavior changes that no one anticipates. And some of those changes can have effects on health, just as drinking less soda might. So the thought that SSB taxes will lead to less obesity and better health is a presumption. It springs from very reasonable speculation. If it is true, then ongoing experiments in taxing these beverages will eventually have a measurable effect.

It’s all good so long as we don’t present the speculation as if it were a matter of fact.

But It Might Be True

In the U.K., the rollout of Boris Johnson’s Better Health campaign unleashed fierce debates. What will work to reduce obesity? Those debates are still raging. Writing in the Guardian, Sarah Boseley laments:

The plan does nothing to capitalise on the gains already made by imposing the sugar tax on soft drinks. Public Health England has been pleased by the amount of sugar taken out of drinks through reformulation by manufacturers. It worked because government wielded a big stick, imposing a levy on drinks with higher sugar levels.

It worked? Not exactly. It might yet have an effect on obesity and health. So far, though, obesity is still high and rising in the U.K.

People crave certainty. But especially in matters of health, we need reliable information. We need to know what is true, what is false, and what is reasonable speculation.

Sticking with the Truth

The truth about obesity is that we don’t know how to prevent it because we don’t precisely know everything that contributed to its rise. Not even close. We have some good ideas about both of those questions, but we don’t have definitive answers. We know how to manage obesity pretty well for most people who have it. But we don’t have any cures. What works for one person doesn’t work for all.

It’s not sparkling or sensational, but honesty works best in the long run – honesty about what’s true, what’s false, and what’s merely our best guess. Serving up speculation as fact is dishonest.

For an intriguing analysis of the language, facts, and speculation in biological science publications, click here. For more on our estrangement from the truth, click here.

The Gray Tree, painting by Piet Mondrian / WikiArt

Subscribe by email to follow the accumulating evidence and observations that shape our view of health, obesity, and policy.


August 6, 2020