The soaring rate of obesity that began in the 1970s and has been climbing ever since mirrors the introduction of a sweetener that's widely used in processed foods, including sodas and fruit juices, a Louisiana State University researcher points out.

In next month's issue of the American Journal of Clinical Nutrition, Dr. George Bray says there's evidence of a link between the use of high-fructose corn syrup (HFCS) and the obesity epidemic in the United States.

Bray -- an obesity expert at the school's Pennington Biomedical Research Center -- says HFCS appears to work differently than other sugars in that it stifles the body's ability to feel full, encouraging a person to eat more. He acknowledges, however, that this behavior hasn't been scientifically proven, according to an account from CBS News.

Many food manufacturers prefer HFCS to cane sugar, since it's cheaper and tastes sweeter, the network reports. A group representing HFCS manufacturers issued a statement denying Bray's hypothesis, saying the corn-derived substance is "compositionally equivalent" to table sugar. The statement points out that obesity also is on the rise in Mexico and Europe, both of which don't use HFCS to the extent that it's used in the United States.