Altered Food May Be Harmful

A new study published in The Lancet found that lab mice fed genetically engineered potatoes developed thickening of their intestines. CBS News Correspondent Elizabeth Kaledin reports it's one of the only studies suggesting that genetically altered foods may cause physical problems ever to be published in a prestigious medical journal.

It's seen as vindication for those who have long condemned the proliferation of genetically engineered foods as dangerous and unnatural.

Andrew Kimbrell, Director of the Center for Food Safety, says "This study suggests that genetic engineering of foods can take a safe food and make it toxic."

Genetically altered foods, in which DNA is changed to improve flavor, survival and durability, have been on the market in the United States for about seven years. We've been consuming them while the debate about whether or not they are safe has been raging.

In the study, lab mice were fed genetically engineered potatoes.

But many scientists believe the new research does nothing to further the debate and clouds the issue with faulty research. The Lancet study is incomplete, they say, lacks adequate controls, and used too few animals, unlike the volumes of research which conclude that genetically altered foods are okay.

"I would give this an F at a high school science fair." says geneticist Val Giddings. "There are abundant data in the scientific literature that are relevant, and they all point out that the foods produced through bio technology are safe."

The British have long protested genetically modified foods and attempted to ban them from the market. Britain's Royal Society of Scientists is concerned that bad science will fuel the fire.

"The difficulty is the bad science is exposed not only to people who are able to criticize it -- other experts in the field -- but it is also exposed to lots of people who have to take it at face value." says Dr. Peter Collins of the Royal Society.

Genetically altered foods are not required to be labeled in the U.S., so perhaps it's no wonder that one small, flawed study saying they harm rats has struck such a nerve -- suggesting that we're uncomfortable with how little we know about how technology is changing our food supply.