Artificial Sweeteners: Are They Safe?

Feb. 13, 2006 — -- The debate over the safety of artificial sweeteners intensified over the weekend, when an article in The New York Times said Aspartame, the most popular sugar replacement in America, might cause cancer in rats.

Aspartame, which was invented in 1965, is found in more than 6,000 products, and most people know it by its trade names, NutraSweet and Equal. It is estimated that 200 million people consume Aspartame so if it is unsafe, the effects could be far-reaching. Dr. David Katz, ABC News' medical contributor, said that people should not jump to conclusions based on the rat study.

"If it caused any significant harm, we would know about it," he said. "If there was any potential for harm, it's a very low level … because of how widespread the use is and because it's been around long enough."

Katz, a Yale professor and the author of the "Flavor Point Diet," said that the latest study, which comes from Italy, demonstrated a "statistically significant increase in lymphomas and leukemias over three years." The Italian researcher studied the effects of about five sodas a day worth of Aspartame on each of the 1,900 rats -- that is the equivalent of 100 ounces of soda for a 150-pound person every day. The Italian doctor also increased the time the rats ingested the chemical.

Katz said: "This is an animal study. There's [nothing] to indicate this is the same threat in humans."

Katz said that rats had short life spans and were naturally more susceptible to cancer. He also pointed out that even healthy foods like broccoli, spinach and beans contained some potentially carcinogenic compounds.

Considering that the average American drinks 837 sodas each year, equivalent to 46 gallons -- and 27 percent of that is diet soda, sweetened with artificial sweetener -- the new study has alarmed many people.

There are alternatives to Aspartame like saccharin (Sweet'N Low) and sucralose (Splenda), which Katz said were not the same chemically, but served the same purpose.

"We seem to have the notion in our society that science is something to be suspicious of and the natural stuff is safe," Katz said. "But we know peanuts are dangerous to some people, and we never discuss banning peanuts."

Katz said there were bigger reasons to be wary of artificial sweeteners.

"I think artificial sweeteners are harmful and, not because of the cancer risk, but because as a class they are 300 times more sweet than sugar," he said. "You may not get calories from diet soda, but because you drink it, you develop a sweet tooth and have these cravings."

If people are worried about getting cancer, Katz said, they should keep their weight down and avoid tobacco. Katz said that the major conclusion he drew from the Italian rat study was that rats and humans were both more likely to develop cancer toward the end of their lives.

"More cancer was seen in this study, and the study's author, Dr. Morando Soffriti, was saying if you're studying cancer, it makes more sense to look at the stage of life when the cancer is likely to crop up."