For Immediate Release
Lab Tests Point to Problems With Trendy New Stevia Sweetener
CSPI Urges More Testing Before Stevia Extract Is Used in Food, Drinks
WASHINGTON - Coca-Cola and Pepsi are planning to introduce new drinks made with
rebiana, an extract of stevia leaves that is 200 times sweeter than
sugar. But according to a new 26-page report by toxicologists at the
University of California, Los Angeles, several, though not all,
laboratory tests show that the sweetener causes mutations and DNA
damage, which raises the prospect that it causes cancer. In a letter to the Food and Drug Administration,
the Center for Science in the Public Interest says the agency should
require additional tests, including a key animal study, before
accepting rebiana as Generally Regarded as Safe, or GRAS.
"A safe, natural, high-potency sweetener would be a welcome
addition to the food supply," said CSPI executive director Michael F.
Jacobson. "But the FDA needs to be as sure as possible that rebiana is
safe before allowing it into foods that would be consumed by tens of
millions of people. It would be tragic if the sweetener turned out to
cause cancer or other problems."
One key animal study has not been conducted, according to
the UCLA experts and CSPI. The FDA's guidelines advise testing
prospective major new food additives on two rodent species, usually
rats and mice. The new sweetener has only been tested on rats, but not
mice. The toxicologists' report said that because several studies found
mutations and DNA damage, a lifetime mouse study designed to evaluate
the risk of carcinogenicity and other health problems was particularly
The new report
was prepared for CSPI by Sarah Kobylewski, a graduate student in the
Department of Molecular Toxicology, and Curtis D. Eckhert, Ph.D., a
professor of Environmental Health Sciences and Molecular Toxicology, at
UCLA. They were assisted by Professor Joseph R. Landolph, Jr., Ph.D.,
of the Department of Molecular Microbiology and Immunology, and
Pathology, Keck School of Medicine, and the School of Pharmacy at the
University of Southern California.
The UCLA toxicologists emphasized the need for more
genotoxicity tests, because of the evidence that derivatives of stevia
that are closely related to rebiana damage DNA and chromosomes. Their
report noted that much of the recent research on rebiana was sponsored
by Cargill and urged the FDA to obtain independently conducted tests to
ensure that corporate biases don't influence the design, conduct, or
results of the tests.
Rebiana is shorthand for rebaudioside A, a component of
stevia. It is obtained from the leaves of a shrub native to Brazil and
Paraguay. Coke, Pepsi, and other companies are excited about rebiana,
because it supposedly tastes better than crude stevia, which is sold as
a dietary supplement in health-food stores. After all the controversies
pertaining to saccharin, aspartame, and other artificial sweeteners,
the food industry expects many calorie-conscious consumers to eagerly
opt for this natural sweetener.
Two companies - Cargill and Merisant - have told the FDA that
rebiana should be considered GRAS, a category given less scrutiny by
the FDA than ordinary food additives. A third company, Wisdom Natural
Brands, has declared that its stevia-based sweetener is GRAS and will
market it without giving evidence to, or even notifying, the FDA. That
company gave CSPI only a heavily redacted report prepared by scientists
it hired to declare its stevia derivative, which is of unknown purity,
Stevia is legal in foods in Japan and several other
countries, but the United States, Canada, and the European Union bar
stevia in foods because of older tests that suggested it might
interfere with reproduction. New tests sponsored by Cargill did not
find such problems.
"I am not saying that rebiana is harmful, but it should not
be marketed until new studies establish that it is safe," Jacobson
Cargill's version of rebiana is called Truvia and would be
used by Coca-Cola. Pepsi's version is called PureVia and is produced by
Merisant's Whole Earth Sweetener division. Merisant is best known for
marketing the Equal brand of aspartame.
CSPI has not questioned the safety of two artificial
sweeteners, sucralose (Splenda) and neotame, but says that suggestive
evidence indicates that saccharin, aspartame (Equal, NutraSweet), and
acesulfame-K pose small risks of cancer.
"The whole issue of what gets GRAS status needs to be
reviewed by Congress," Jacobson said. "It's crazy that companies can
just hire a few consultants to bless their new ingredients and rush
them to market without any opportunity for the FDA and the public to
review all the safety evidence."
Two of the most harmful ingredients in the food supply are considered GRAS: salt, which raises blood pressure and causes thousands of unnecessary heart
attacks and strokes every year, and partially hydrogenated oil, which is the source of artery-clogging artificial trans fat. CSPI has long campaigned to get partially hydrogenated oil out of the food supply and to reduce salt to safe levels.