The glycaemic index, a method established to rank foods based on the rate of carbohydrate absorption they trigger, is seeing increasing interest from researchers and the food industry as a way of reducing risk for obesity and obesity-related disease. More than 300 papers investigating the relatively new approach have been published in the last year.
But research still has a long way to go, notes Dr Julian Stowell, director of scientific affairs for Danisco Sweeteners.
"For people with established diabetes, there is quite clear evidence that moving to a low GI diet is advantageous. But for healthy individuals, it is not so clear," he told NutraIngredients.com.
But with one-third of western European consumers currently overweight, rising to almost half by 2006, there is a clear incentive to invest in new approaches to diet. And emerging evidence shows that eating foods with a low glycaemic index may help people to eat less calories, said Dr Stowell, also chairman of the US-based Calorie Control Council , which represents the reduced calorie foods and ingredients industry.
A study published in Pediatrics (Nov;112(5):e414) last year found that children eating a low GI breakfast tended to eat more moderately throughout the day while those eating a high-GI breakfast were more likely to be hungry by lunchtime.
But intervention studies, to assess the benefits of a low-GI diet over the long-term in a larger population group will require significant resources, and means that definitive proof for the value of the glycemic index may be some way off.
In addition, the forthcoming European regulation on health claims does not include a reference to GI in its initial draft and while an informal dialogue with regulators has been initiated by industry to allow for GI health claims, it not yet clear whether these claims will be allowed.
However those willing to invest in low-GI foods early on will benefit the science, according to Dr Stowell, in turn helping to support the bid for a future health claim.
"Only by consumers adopting low-GI nutrition strategies will we convince sceptics," he said.
UK supermarket chain Tesco has begun introducing GI labeling on some of its foods while some food manufacturers are making reference to the nutritional strategy in supporting literature.
"I think food manufacturers have a moral obligation to offer healthy foods. Even if you can't market a food by saying that it has reduced GI, if you can actually produce it and offer it to consumers, that's a start," he said. "The baked goods, dairy and confectionery sectors all have something to offer."
He added that the Atkins diet, which focuses on low GI-foods in its latter stages, already embraces the low-GI nutritional approach and companies developing 'low-carb' foods could be seen as contributing to support for the GI.
"It is wrong to view GI as a rival to Atkins. I see it as a continuum," he said.
A quarter of the Europe or US-based food and drink companies recently interviewed by Reuters Business Insight said they are actively investing in the research and development of new low-carb products. And the whole European dieting market is forecast to be worth over €100 billion in 2007.
Dr Stowell was a speaker at a recent Leatherhead Food conference on the Glycaemic Index.