Too much choice can make us overeat, study finds

Choice is usually a good thing - except when we have too much to choose from. This is true in most aspects of life, but particularly when it comes to food. Researchers have found that too much choice can actually be bad for our health.

People who eat different types and brands of a particular food, such as pizza, are more likely to overeat than those who tend to stick to the one brand, researchers from the Universities of Liverpool and Bristol have found.

Since the 1970s, the number of varieties of the same food product has increased astronomically. The calorie content of these foods can vary widely, thanks to the use of low-energy sweeteners and fat substitutes.

Having identified more than 70 different types of pepperoni pizzas available through supermarkets and takeaway suppliers, the researchers examined the eating behaviours of nearly 200 participants. The participants fell into one of two camps: those who ate many different brands and varieties of pepperoni pizza; and those who generally consumed the same brand and type of pizza.

Within these 70 different brands and types, the calorie content differed by more than 300%, with a calorie range of 501 to 1909 calories per pizza.

The researchers found that participants who regularly ate different varieties failed to compensate for the calories at a later eating occasion and went on to eat more additional food than the participants who stuck to the same brand - and were more likely to believe that a slice of pizza would be less filling.

“We used pepperoni pizza in this study, but it could apply to other mass-produced food items which are available to buy in many varieties and by many manufacturers,” said Dr Charlotte Hardman from the University of Liverpool’s Institute of Psychology, Health and Society.

“It would appear that this high variability of food items makes it more difficult for people to learn about food and manage their consumption, which exposes a new feature of Western diets and which has potential health implications.”

The research was published in the journal PLOS ONE