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‘It’s Low-Fat, So I Can Eat All I Want!’

Consciously or not, that seems to be what we tell ourselves as we shop for food.

By Tom Jacobs


(Photo: Spencer Platt/Getty Images)

Ever wonder why, after switching to low-fat foods, you haven’t lost weight — or even gained a few pounds? Well, newresearch presents one possible reason: People who choose these relatively healthy items tend to purchase larger amounts of such foods, which increases the amount of calories they consume.

What’s more, researchers in the Netherlands report, this “overconsumption effect” persists over time, as eating larger amounts of food becomes the norm.

“Instead of reducing the obesity problem, low-fat products may enhance the problem in this long run,” a research team led by Kathleen Cleeren writes in the International Journal of Research in Marketing. “Motivating consumers to buy these products can result in negative long-term consequences, in which consumers persistently continue buying more products, and consuming more calories.”

Previous research has produced similar results: A 2006 study found a “low-fat” label leads people to overeat snack foods, especially if they’re already overweight. Cleeren and her colleagues wanted to see if these laboratory studies would be duplicated in the real world, and whether their effects would persist over time.

“Instead of reducing the obesity problem, low-fat products may enhance the problem in this long run.”

They used data from the Dutch Gfk household scanner panel, focusing on 311 households that met a specific criterion: Each “made the first purchase of a low-fat chips/crisps product between 2004 and 2007.” Their patterns of purchasing foods in this category (potato chips, corn chips, and the like) were noted for the year before this first sampling of a low-fat option, and the year after.

The good news is people who switched to, say, baked chips did not compensate by buying more high-fat items. The bad news: They did purchase — and, presumably, eat — more of their new low-fat snack than they did of the old, higher-fat variety.

As a result, “The first low-fat purchase leads to an increase in monthly purchase volume and calories, in the short- and long-run,” the researchers report. “Overpurchasing, in the long run, is due to adding too many low-fat items to the basket, without decreasing the amount of regular products.”

The results suggest consumers need to be educated as to how much low-fat food is actually healthy. But the researchers caution such a campaign may not be effective, since the effect they found is likely driven by “psychological mechanisms that are rather complex and unconscious.”

“Policy makers should thus be very careful in embracing the introduction of low-fat products as a solution for the obesity problem,” the researchers conclude. “In the end, it seems that consumers and society are worse off, as (a consumer’s) first low-fat purchase increases food consumption and calorie intake.”

Perhaps just a small amount of a truly satisfying snack is better than opting for a low-fat version that has you eating more in the forlorn hope of getting the same buzz.