While there is a large segment of the population always looking for healthier, lower-calorie food options, there are some shoppers who like the things they buy just the way they are — and who react negatively when their favorite foods are tweaked. Is there a way to get these folks consuming fewer calories?

Maybe just don’t tell them they’re eating a lower-cal version, suggests a new study, published this week in the International Journal of Behavioral Nutrition and Physical Activity. Researchers at the University of Copenhagen wanted to find out if “silent reformulation” — cutting calories from store-brand processed foods without explicitly telling people it’s different — could be a good way for retailers to contribute to lower calorie intake in the population.

The researchers note that often when foods are reformulated to contain lower fat, sugar, or salt content, some consumers may feel like they can now comfortably get those uneaten calories, etc., from other foods.

In other cases, product reformulation might change the perceived quality of the products — for example, a reformulated product could be considered a “diet” product — which could undermine their effectiveness, the authors of the study point out.

The switcheroo

Researchers looked at a full year’s worth of sales data from March 2013 to 2014 that included figures on eight product categories from a Danish retail chain. In each category, certain store-brand products — mayonnaise, fruit yogurt, pumpkin seed rye bread, buns, yogurt bread, carrot rolls, whole grain rolls, and chocolate muesli — were reformulated with the intention of providing a healthier product to customers.

How many calories were cut differed for each product: Mayo and fruit-flavored yogurt cut calorie content by about 16-17%, while for bread products the reduction was 5-10%, and chocolate muesli only had 2-3% reduction in calories.

The reformulations were not truly secret. The nutrition label on each product was updated to reflect the changes. However, the supermarket chain made no effort to announce or advertise that reformulations had occurred, nor did it change any of the prices on the affected products.

The results

Researchers ultimately found that for all products, silent reformulation translated into a reduction in the sale of calories. In other words, shoppers generally continued purchasing these products, and the total amount of calories in their carts declined.

But in some products, the effects of substitution were outweighed by the positive effect.

The changes didn’t seem to have any drastic net effect on sales for the retailers. At worst, some of the products experienced “very moderate” dips in sales value, while other sales remained the same or even increased after reformulation.

“Based on these findings, ‘silent’ reformulation of retailer’s private brands towards lower energy density, seems to be a promising strategy for the retail sector to contribute to lower calorie intake in the population, and thus supportive of public health goals and industry’s incentive to undertake also modest and silent reformulations,” the study’s authors concluded.

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