Nutrition Superstition: Snacking

Nutrition superstition is front and center in an absurd fight over nutrition guidance in the UK. On the cover of the report that started the UK’s current tussle, you’ll find one such superstition: “avoid snacking to reverse obesity and type 2 diabetes.”

The purveyors of this superstition – the National Obesity Forum and the Public Health Collaborative – are apparently unburdened by the need for scientific evidence to support their claims.

In a 2015 review of myths and presumptions about obesity, Krista Casazza and colleagues described the idea that snacks contribute to obesity as a presumption. They found plenty of authoritative assertions that snacking is “a major culprit in the obesity epidemic.” They found evidence that it has increased. But they also found a lot of confusion about definitions for snacking versus eating frequency. It’s tough to study something that hasn’t really been defined.

But more to the point, when they looked for evidence from randomized, controlled trials of snacks, they found:

In none of these studies was a difference detected between the snacking versus the non-snacking study arms with respect to measurements of obesity including weight, weight change, BMI, body fat percentage, waist circumference, or waist-to-hip ratio.

Snacking, like any other eating habit, can get out of control. The solution is to cultivate healthy patterns of meals and snacks that are satisfying and sustainable. Simplistic prohibitions often prove to be unsustainable.

And more broadly, when health policy is governed by suspicions and presumptions, we risk replacing science with superstition. So we should not be surprised if epidemic rates of obesity do not yield to policies guided by mere presumptions.

Click here for the review of myths and presumptions by Casazza et al.

Snack Time, photograph © BPPrice / flickr

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

June 1, 2016