CARRAGEENAN UNDER FIRE
CARRAGEENAN UNDER FIRE
Should clients avoid this popular food
additive to protect gastrointestinal health?
Carrageenan may be the most
controversial food additive that many people have never heard of. Although it
has been used for decades as a thickening agent in a wide variety of foods, a
growing body of evidence is raising questions about its safety. Those who seek
its removal from the food supply point to studies that have linked carrageenan
to digestive diseases, inflammation, and even cancer.
To date, the FDA
has rejected calls to ban the additive, citing several studies that have not linked carrageenan to harmful health effects. This lack of agreement may leave nutrition professionals wondering how best to counsel clients.
has rejected calls to ban the additive, citing several studies that have not linked carrageenan to harmful health effects. This lack of agreement may leave nutrition professionals wondering how best to counsel clients.
A recent report by the Cornucopia
Institute, a corporate and governmental watchdog group, makes a case for
banning carrageenan.
The March report cited several studies
that have used animal models as well as human cell cultures to demonstrate carrageenan’s
harmful effects. The report stated that experts have known about these adverse
effects for decades.
“Starting in the late 1960s, research
linked the type of carrageenan used in food to gastrointestinal disease in
laboratory animals, including ulcerative colitis-like disease, intestinal lesions,
and colon cancer,” according to the report.
Part of the controversy stems from the
fact that carrageenan has been used in food for a long time; it was
grandfathered in as a safe additive in the 1970s, avoiding a lengthy regulatory
process.
The FDA doesn’t believe the available
evidence makes a strong enough case to ban it, noting that none of the studies have
been done on human subjects, and they did not replicate the conditions that
exist in the human digestive system.
Why All the Hubbub?
Carrageenan can be found in many types
of products, including cheese, ice cream, bread, jelly, jam, and some processed
lunchmeats. It’s often used as a stabilizer in beverages whose contents are
known to separate, such as chocolate milk and
nutritional supplements. It also may be
found in products made with a carrageenan-containing ingredient, such as pies
that use condensed milk, although it may not be listed on the product’s ingredient
list. It doesn’t contribute any nutritional value or
improve taste, safety, or shelf life.
Carrageenan is derived from red seaweed,
and alkali or acids are used to separate it from its source. When acid is used,
it causes the carrageenan to degrade to a lower molecular weight than
carrageenan processed with alkali. Highermolecular- weight carrageenan often is
referred to as “food grade,” while low-molecular-weight carrageenan is referred
to as “degraded.” This difference presents a significant challenge in assessing
the additive’s safety.
In June 2008, Joanne K. Tobacman, MD, an
associate professor in the department of medicine at the University of Illinois
at Chicago, filed a citizen petition with the FDA to ban carrageenan. In her petition,
Tobacman cited several studies she coauthored that found harmful effects
associated with the additive. The studies used amounts of food-grade carrageenan
that are lower than those ingested in the typical American diet. In each study,
the food-grade carrageenan caused inflammation.
Tobacman says carrageenan, whether food
grade or degraded, predictably causes inflammation because of its chemical
structure and says thousands of studies over several decades have demonstrated
this effect. She adds that the acidic conditions in the human digestive system
likely will cause foodgrade carrageenan to degrade in the body.
In response, the FDA wrote, “Data from
published studies are divided on the issue of possible degradation of
carrageenan in the body. While the possibility of carrageenan
degradation has been raised in some in
vitro and in vivo studies, more recent carefully designed dietary studies have failed
to confirm significant carrageenan breakdown in the gastrointestinal tract.”
But the broader question is whether it’s
possible to effectively separate high- and low-molecular-weight carrageenan. FDA
regulations don’t include a specification that addresses low-molecular-weight
carrageenan, but the European Union has proposed a threshold of no more than 5%
of the total volume of carrageenan.
In an attempt to quantify the ideal
ratio of degraded to food-grade carrageenan, Marinalg International, a
carrageenan producers consortium, wrote a technical paper in
2003 to determine whether there’s a
reliable method of measurement.
Eight of the 12 samples studied exceeded
5%, with the highest approaching 25%. In November 2005, the paper’s authors
concluded that “the Working Group has not found a method for molecular weight
distribution measurement that is sufficiently accurate and reproducible to
yield a validated and defensible method.”
While the question of how to separate
degraded from foodgrade carrageenan may not be clear or whether it’s even possible,
a larger point of contention is how food-grade carrageenan affects the human
body. Although the harmful effects of degraded carrageenan have been well
documented, as mentioned, studies of food-grade carrageenan have focused on
only animal and cell culture models. The FDA doesn’t consider these models to
be analogous to the way people come in contact with carrageenan.
“All the studies discussed in the five
publications submitted in Dr Tobacman’s citizen petition used in vitro cell or tissue
culture models,” the FDA states. “The regulations
for carrageenan permit its use on or in
food for human consumption. As such, a safety study in which the test subjects are
exposed to carrageenan as part of their diet would be more appropriate for
evaluating the safety of exposure to carrageenan through human consumption.”
Because of carrageenan’s inflammatory
properties and potential to cause other harmful effects, along with the fact
that Tobacman is convinced degraded carrageenan can’t be effectively isolated
from food-grade carrageenan, she believes it would be unethical to perform
studies on humans. For these reasons, she advocates banning the additive. She
also notes that carrageenan consumption varies widely, and some people may be
consuming significantly higher amounts than what’s considered average:
250 mg/day, up from 100 mg in the 1970s.
Tobacman’s advice to dietitians is to consider carrageenan as a possible source
of digestive illness in their clients.
“I think dietitians who confront
patients with inflammatory disorders should clearly recommend they try to avoid
carrageenan in their diets and see if that makes any difference,”
she says. “And as we become more and
more aware of inflammation being a factor in other chronic disorders, in
addition to colitis—as we see it in diseases such as atherosclerosis and
diabetes—I think there’s even more of an imperative to advise people to avoid
something that clearly can bring on inflammation.”
RDs Weigh In
Not everyone, however, agrees with
Tobacman. Joy Dubost, PhD, RD, CSSD, a food scientist and spokesperson for the
Academy of Nutrition and Dietetics, believes the FDA is correct in taking a
slow and steady approach, and she sees no reason to sound the alarm about
carrageenan. She believes researchers will continue to study the effects of
carrageenan but says she has no plans to alter her advice to clients based on
the current scientific literature.
“Now, with that said, there’s still
individual choice,” Dubost says. “So if consumers are concerned about
carrageenan or feel that they may be having a specific flare-up, then of course
I’m going to advise them that they may want to read the labels. Some companies
are removing it from their products, but there are quite a few that aren’t. The
key would be reading the product label and the ingredient statement. But at
this point, as far as general guidance,
I would not say to avoid it based on the scientific evidence.” Lona Sandon,
MEd, RD, LD, an assistant professor in the department of clinical nutrition at
the University of Texas Southwestern Medical Center at Dallas, says there are
several difficulties in applying existing research to a typical diet. One is
that there are no studies showing what happens, for example, when someone eats
salad dressing containing carrageenan. The presence of other foods and
ingredients may change the way carrageenan reacts with intestinal cells.
Furthermore, no studies
exist that quantify a toxic dose in the
context of a human diet and, as Sandon notes, “the dose makes the poison.”
Typically, carrageenan is low on the list of ingredients in foods, indicating that
it’s present in small amounts.
Like Dubost, Sandon isn’t changing the
way she counsels clients at this time, but she does believe the existing
research raises important questions and more studies must be done.
In the meantime, the debate about
carrageenan’s safety is likely to continue, but there’s one piece of advice on
which everyone can agree: “If people are concerned about something like
carrageenan, it kind of goes back to the message we often give and that’s to
choose most of your foods from whole, natural foods,” Sandon says. “If most of
your diet includes fruits, vegetables, and whole grains, you’re avoiding this
additive.”
All Fitness __ CARRAGEENAN UNDER FIRE
— David Yeager is a freelance
writer and editor based in Royersford, Pennsylvania.
Foods That May Contain Carrageenan
Chocolate milk
Ice cream
Sour cream
Cottage cheese
“Squeezable” yogurt
Soymilk
Almond milk
Hemp milk
Coconut milk
Soy desserts
Soy pudding
Sliced turkey
Prepared chicken
Nutritional drinks
Canned soup
Broth
Microwaveable dinners
Frozen pizza
— Source: Cornucopia Institut
Foods That May Contain Carrageenan
Chocolate milk
Ice cream
Sour cream
Cottage cheese
“Squeezable” yogurt
Soymilk
Almond milk
Hemp milk
Coconut milk
Soy desserts
Soy pudding
Sliced turkey
Prepared chicken
Nutritional drinks
Canned soup
Broth
Microwaveable dinners
Frozen pizza
— Source: Cornucopia Institut
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