Obesity Research: Skipping from Links to Causes

Every day, news feeds are crammed with studies of more and more factors that link to obesity and health. But well-controlled obesity research to tell us about cause and effect is rare by comparison.

The latest example is a study published in the American Journal of Obstetrics and Gynecology that found a 32% higher risk of obesity for women who gave birth as teens than women who gave birth later in life. “Pass it on,” the health reports tell us without hesitation.

Does Facebook cause obesity? Air conditioning? Restaurants? Diet soda? These and scores of other facts of daily life are linked to obesity through inconclusive studies that show a link but prove nothing about cause and effect in free-living humans.

Similar links are made between dietary and lifestyle factors that raise hopes of solving our weight problems. Follow a Mediterranean diet. Eat more dairy. Eat more protein. This sort of advice circumnavigates a common sense question. How can eating more of anything lead to weight reduction? But in the world of wishful thinking, it works.

In a recent New York Times commentary, philosophy professor Gary Gutting cautions that “Media reports saying ‘studies show . . .’ are most often giving us highly tentative results — indeed, results that are likely to be false.  They need to be labeled as such.”

So we have an abundance of clues and a dearth of conclusions about causes and cures for obesity. Gary Taubes, David Allison, Francis Collins, and a litany of others have called for a more ambitious obesity research agenda to solve the problem. Says Allison:

Although experimental tests can be challenging, not all are unduly so. Many conjectures commonly advanced as recommendations to reduce weight gain or promote weight loss – “eat more meals with family members,” “reduce fast food availability,” “eliminate vending machines from schools,” etc. – could be tested and we should challenge ourselves to do so more often.

The time to take this challenge is now. The cost of educated guesses is too high.

Click here to read the study on teen pregnancy and obesity risk, click here for the Gutting commentary, click here for the Taubes commentary, click here for the Allison commentary, and click here for the Collins commentary.

Ripple Effect image © Agustín Ruiz / Wikimedia

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