It's bye-bye to Atkins and hello to GI

Manufacturers have a "tapestry of opportunities" to capitalise on the low-glycaemic index (GI) diet by altering processes or reformulating products, a leading scientist has claimed.

Jeya Henry, professor of human nutrition at Oxford Brookes University, said manufacturers had the opportunity to "exert real control over GI by the judicious use of raw materials, formulations and processing conditions". Tesco plans to add GI labels to 1,000 products by the end of 2005 and Sainsbury launches GI labels this month.

Henry added: "If the manufacturing process builds a structure that hinders gelatinisation [swelling of starch granules] and enzyme access, GI will be lowered. If it destroys the native structure of the starch, GI will be high."

The low-GI diet was "the single most important nutritional revolution" in recent years and a massive commercial opportunity for manufacturers, he added. "This is going to change the face of our approach to weight control and to an array of diseases from diabetes to obesity. It is not a passing phenomenon."

However, replacing sugars and flour with a host of artificial ingredients or added fat or flavours to mask unsavoury tastes was not the way forward, he said. "You have to be responsible or you send out mixed messages. You can use natural ingredients like barley and oat fibre."

The GI measures how quickly carbohydrates are broken down and released as glucose into the bloodstream. High-GI foods such as sugary snacks, white bread and rice release energy quickly but leave you feeling hungry again soon afterwards. In contrast low-GI products assist weight control by releasing energy more slowly, staving off hunger pangs.

"We've moved on from Atkins. Carbs are not all bad," said Tesco's head of brands, diet and health, Hamish Renton. The concept of "foods that make you feel fuller for longer" was moving into the mainstream, he said and Tesco was keen to engage with "pro-active suppliers" looking at ways to reformulate.