SHOPPERS are being duped by so-called low-fat foods that are packed with calorie-laden sugar, health experts warn.
Professor Kerin O'Dea, of St Vincent's Institute in Sydney, said food manufacturers were using increasing amounts of fructose — a cheap, sugary corn syrup — in the products to improve taste.
Fructose was high in calories and there was growing evidence that it was addictive, she said.
"The argument that obesity is driven by high fat intakes has led to a proliferation of low-fat processed foods," Professor O'Dea said. "But many of the lowfat products, especially the '99% fat free', are loaded with sugars and kilojoules," she said. "If you reduce the percentage of fat in a product, the proportion of other nutrients is altered; either carbohydrate or protein needs to increase."
Fructose can be found in many low-fat yoghurts, breakfast cereals, breakfast and snack bars, juice (especially apple), diet cordials, sauces, salad dressings and "lite" peanut butter.
Professor O'Dea said fructose was dangerous because it did not make people feel full as it did not stimulate insulin secretion or leptin, the two hormones that affect appetite and satiety.
"You can consume fructose and not feel like you have eaten much. It does not make people feel full and it is getting under the radar," she said. "And if you are well nourished and don't need it, then the fructose goes through the liver and is converted into fat.
"While fructose was added to low-fat products to improve the taste, food manufacturers found the holy grail because people started consuming more of it because they thought it was healthy and they were still hungry."
"People would be better off eating a full-fat plain yoghurt than a low-fat yoghurt."
Professor O'Dea said fructose was often identified with other chemical names or as sugars on labels.
Consumers should look out for corn syrup and hydrolysed corn starch on labels, which hide fructose content, and sucrose, which is half fructose.