Science weighs in on sugar substitutes and its relationship to cancer.
Artificial sweeteners promise the taste of sugar without the calories, a trade-off leaving some medical professionals and scientists cautious and others confident in the safety of sugar substitutes.
Weighing the risks and benefits is of growing importance since 86 percent of Americans use low-calorie, reduced-sugar or sugar-free foods and beverages, according to a 2007 survey by the Calorie Control Council.
Concerns, in part, focus on possible connections between artificial sweeteners and cancer. The
history of saccharin—used first in foods in 1900—offers an example. In the 1970s, research on rats linked the sugar substitute to urinary bladder cancer, but later studies indicated the risk was limited to rats.
Similarly, the Food and Drug Administration regulates artificial sweeteners, and no studies have found clear evidence tying FDA-approved sweeteners to cancer. The FDA has approved five sugar substitutes: saccharin, aspartame, acesulfame potassium, sucralose and neotame. Rebaudioside A, a purified component of the stevia plant, received a GRAS notice, marking it “Generally Recognized As Safe.”
However, research continues. A 2007 study conducted on rodents points to possible links between aspartame and cancer, including lymphomas and leukemias. Other studies support aspartame’s safety.
For the average consumer, unraveling all of the sometimes conflicting science is difficult, says Linda A. McCauley, dean of Emory University’s Nell Hodgson Woodruff School of Nursing, who co-authored a study evaluating artificial sweeteners.
There are no clear guidelines for evaluating the risks. And most consumers would be shocked by the limited research done before products like sweeteners appear on store shelves, McCauley says.
Information is often limited because many studies are funded by companies developing the products, and the information is not released to the public, she says. “It’s not exhaustive testing,” she adds. “It’s very select testing, and it only studies the amount that would be a safe dose and not cause acute toxicity in humans.”
When used in moderation, however, sweeteners are likely OK for most people, McCauley says. “We go through our lives making decisions about the level of risk we expose ourselves to—including smoking, artificial sweeteners and using cell phones,” she says.
With fears about artificial sweeteners often ramping up online, consumers should take a step back, says D. Milton Stokes, MPH, RD, a private-practice nutritionist in Connecticut.
“Despite the urban legends and despite the chain emails that won’t go wherever emails should go to die, I have not seen systematic evidence confirming that non-nutritive sweeteners cause health problems,” he says. “In 20 years, we may have a study that shows a cause-and-effect relationship, but we don’t have that data. The only thing we have now is speculation and anecdote, and it really leads to patient confusion.”
Two servings of non-nutritive sweeteners daily is the recommended limit, about two cans of diet soda or two cups of diet yogurt, Stokes says. Also when faced with losing weight, people should look beyond sugar intake. “We want consumers to have a total-diet approach, meaning we want to see some real whole foods in their diets,” he says.
Particularly for patients receiving treatment for cancer, diet needs typically focus on weight maintenance and not weight loss, Stokes says. “That said, I have zero hesitation saying to someone with cancer that they can have a diet soda or a light yogurt, if that’s what they want.”
Despite the urban legends and despite the chain emails that won’t go wherever emails should go to die, I have not seen systematic evidence confirming that non-nutritive sweeteners cause health problems.