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Spoilt by Choice

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By David Raubenheimer & Stephen J. Simpson

Our supermarkets provide a wide variety of foods, so why do more than a billion people worldwide eat more poorly than hunter-gatherers? A study conducted in a Swiss chalet was the starting point to test a theory.

David Raubenheimer is Professor of Nutritional Ecology and Director of the Bachelor of Natural Sciences degree at Massey University. Professor Stephen Simpson is ARC Laureate Fellow in the School of Biological Sciences, and Academic Director of the Charles Perkins Centre, the University of Sydney.

The full text of this article can be purchased from Informit.

The variety of foods now available is unprecedented in history, yet more than a billion people worldwide are overweight or obese. Considering the immense disease burden that this imposes on society, it seems that humans are not very good at making the most of the privileged times in which many of us live.

The same cannot be said for other animals, even humble invertebrates. For example, when fruit flies and hunting spiders are given combinations of foods that vary in their nutritional balance, they select a diet from these that supports maximal reproduction (which, in evolutionary terms, is the best possible outcome).

Why do people overconsume energy rather than selecting a healthy diet from the great variety of foods available? Much of the research into this question has focused on the two nutrients that are commonly associated with obesity: fats and carbohydrates (notably sugar). Our research has suggested that to understand the curious nutritional behaviour of our species we need to focus on the relationship between these and the third energy-providing macronutrient: protein.

Our first experiment, performed with the help of Oxford undergraduate student Rachel Batley, provided a fascinating clue. We offered 10 of Rachel’s colleagues free board and lodging in a Swiss chalet on the condition that they selected their meals from a prescribed menu and...

The full text of this article can be purchased from Informit.