In a statement, the National Soft Drink Association said the findings, which suggest artificial sweeteners may disrupt the body's natural ability to 'count' calories, contradict earlier research that shows the use of aspartame in foods and beverages can help with weight loss and long-term control of body weight.
"The Purdue University rat studies amounted to pure speculation and are in sharp contrast with the findings of a number of peer-reviewed scientific studies involving humans that have been published in prestigious journals," said Kathleen Dezio, spokeswoman for the National Soft Drink Association (NSDA).
"Those studies showed that the notion that sweetness in non-caloric or low-caloric foods leads to a disregulation of food intake in humans is simply untrue," she added.
The Purdue study, published in the July issue of the International Journal of Obesity, conducted by Professor Terry Davidson and associate professor Susan Swithers, suggests artificial sweeteners may disrupt the body's natural ability to 'count' calories based on foods' sweetness. They claim their findings may explain why increasing numbers of people in the US lack the natural ability to regulate food intake and body weight.
"Our hypothesis is that experience with these foods interferes with the natural ability of the body to use sweet taste and viscosity to gauge caloric content of foods and beverages," reported Swithers.
But, to the contrary, the drinks industry group quotes research conducted by Dr. George Blackburn at Harvard Medical School that found aspartame intake was 'positively correlated with weight loss and weight maintenance' as well as studies by researchers at the University of Illinois (Birch, et al, 1989) and the University of Toronto (Anderson, et al, 1989) that found replacing sugar with a high intensity sweetener in foods or beverages 'does not affect food intake or hunger in children'.
"The Purdue study also used flawed methodology, which brings into question the accuracy of its conclusions for rats or humans. The researchers did not report if the rats consumed equal amounts of low-calorie and regular sweeteners," asserted the soft drinks group.
Diet soft drinks claim the biggest market share for artificial sweeteners, with over 87 million consumers in the US alone. According to a 1998 survey commissioned by the Calorie Control Council, 144 million American adults consume low-calorie, sugar-free products on a regular basis.
Options for food and beverage makers in artificial sweeteners currently include FDA-cleared acesulfame potassium, aspartame and saccharin.