Virtual Food Components Take the Guesswork Out of Healthy Eating

Newswise — Nutritional information as provided on food labels tell us little about the effects various food components actually have on our body. But that could change, thanks to a novel concept described by New Zealand researcher Dr John Monro in Journal of the Science of Food and Agriculture this month " the use of virtual food components (VFCs) to evaluate the real physiological effects of what we eat.

VFCs are nutrient-like values that allow food data to say not only what a food is, but also what it does, and how well it does it.

"In a world flooded by functional foods, there is a real need for values that can represent food effects that can't be shown in traditional panels" , says Monro, of the New Zealand Institute for Crop and Food Research in Palmerston North. "Important though nutrient values are, they can be hopelessly inadequate for communicating the benefits of foods."

Like traditional nutritional information, VFCs are presented as weights. They provide information about the functional efficiency of a food, by comparing the effect of that food with a suitable reference material of known activity.

For example, Monro's first VFC " glycaemic glucose equivalent (GGE) " is a measure of the glucose-raising potential of a food, compared to glucose. The activity of the test food is deduced as a percentage of the activity of an equal amount of the reference food. Thus a food with a GGE of 15 would impose the same blood glucose level as 15g of glucose. It is like saying how much of the reference is in 100g of the food.

In JSFA, Monro and colleague Eva Martinet describe a second VFC " wheat bran equivalents for faecal bulk (WBEfb) " and show how an effective food product for bowel regularity could be designed from knowledge of the VFC content of its ingredients, but not from its dietary fibre content.

Whereas WBEfb expresses bulking efficiency, dietary fibre is a completely unreliable guide to the effect of fibre on the body, given that some fibres are actually destroyed by fermentation in the colon, and thus do not contribute bulk.

Both GGE and WBEfb have significant implications for human health. The blood glucose-raising potential of a food has been linked to obesity, heart disease and cancer, and in individuals with impaired glucose tolerance, e.g. those with diabetes, to blindness and kidney failure. And, despite its unglamorous nature, colonic bulk provides significant protection against a range of bowel disorders. Rates of colorectal cancer, (among the four most common cancers in the UK and US), soar as faecal bulk drops below 150-200 g per day.

"We now intend to build up the data so they can be used across a wider range of foods" , says Monro.

But some parts of the food industry have already cottoned on to the potential of VFCs; the hugely successful Atkins diet's 'Net Atkins CountTM' is none other than the GGE first described by Monro almost five years ago, before he coined the term VFC in 2004.

Despite their virtual nature, VFCs could show up the real performers amongst the hundreds of so-called functional foods that flood supermarket shelves these days.

"Virtual food components are a way of helping people to match their foods with their needs," says Monro. "Once they know how responsive they are to a certain level of a VFC in one food, they can use the information to predict how other foods will affect them."

About the Journal of the Science of Food and AgricultureThe Journal of the Science of Food and Agriculture (JSFA) publishes peer-reviewed original research and critical reviews in these areas, with particular emphasis on interdisciplinary studies at the agriculture/food interface. This international journal covers fundamental and applied research.