Carrageenan is a
broad term used to describe a variety of
food-grade polysaccarhides (and a non food-grade derivative
which is technically known as poligeenan)
obtained from many different species of
seaweed. Food-grade carrageenan has been
used in cooking for hundreds of years as a
thickening, stabilizing and gelling agent.
Carrageenan is commercially produced in three forms:
iota, kappa and lambda. Each form is derived
from different species of seaweed, possess
different molecular structures and are used
for different purposes in food applications.
Lambda carrageenan is widely used in many
commercial vegan foods, such as salad
dressings, veggie dogs, plant milks and ice
creams, just to name a few. Irish Moss
(Chondrus crispus) is a commonly
known source of carrageenan (it contains about 55% by
weight) and is frequently used in the
homebrewing of beer as a clarifying agent.
For the block and wheel cheeses in The
Non-Dairy Evolution Cookbook, kappa
carrageenan is used as a firming agent to
provide textures ranging from soft to very
firm. It is essential for producing the
finest non-dairy cheeses that mimic dairy
cheeses in texture and melt-ability. Iota
carrageenan is used to replace the function
of gelatin in my marshmallow recipe. Please
note that these specific cheeses are the
only recipes that call for kappa carrageenan
and the marshmallows are the only recipe
that call for iota carrageenan. This keeps carrageenan consumption
to a minimum.
However, I occasionally have readers who
still express concerns over the inclusion of
carrageenan in these recipes and I have
found it necessary to defend its use. Their
concern is based upon research studies of
carrageenan by Dr. Joanne Tobacman, an
associate professor at the University of
Illinois in Chicago, who made claims that
this naturally occurring seaweed derivative
causes gastro-intestinal inflammation and
pre-cancerous lesions when fed to small laboratory animals.
What many don't realize is that Dr. Tobacman
was actually studying a moleculary
degraded form of carrageenan called
poligeenan, which has never been
used in food applications, and is used in
other applications such as barium contrast
solution for X-rays and CT scans
(unfortunately, the broad term "carrageenan"
is often and erroneously used to describe
both poligeenan and food-grade carrageenan,
which causes confusion between the two). She then
suggested that human digestive acids can
convert food-grade carrageenan into the
degraded form, but without any living
organism studies to support her theory.
Conducting a controlled study of food-grade
carrageenan would seemingly be impossible
since the term does not refer to a single
substance derived from a single source.
Dr. Tobacman filed a petition with the FDA
in 2008 asking a revocation of carrageenan as a food additive, but the FDA denied
her petition in June of 2012. She also
lobbied the National Organic Standards Board
and was rejected. Her research credibility
is also flawed by the fact that she tried to
have carrageenan declared as an unsafe food
additive based upon weak technical arguments
a decade before the University research
regulatory agencies in the United States,
the European Union and the United Nation's
Food and Agriculture Organization/World
Health Organization (FAO/WHO) repeatedly
review and continue to approve carrageenan
as a safe food additive.
Regardless of the flawed studies and
rejected theories, a number of professional
and self-appointed consumer watchdogs have
revived Dr. Tobacman's anti-carrageenan
crusade, producing numerous web pages filled
with words condemning carrageenan as an
unsafe food additive for human consumption.
This negative media hype has prompted a
demand for food companies to remove carrageenan as a food
additive. While some food companies are
yielding to this consumer pressure, other
food companies are treading more cautiously
since the research studies are flawed and
scientific evidence is lacking.
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.”
Poligeenan (previously known as "degraded
carrageenan" in scientific and regulatory
publications) is considered a possible
carcinogen to humans; food-grade carrageenan
is not. The only relationship between food
grade carrageenan and poligeenan is that
carrageenan is the starting material for
creating poligeenan. Poligeenan is not an
inherent component of carrageenan and cannot
be produced in the digestive tract from
carrageenan-containing foods because the
production process for poligeenan requires
high temperature treatment of carrageenan
with strong acids for an extended period of
time. This completely alters its molecular
structure and molecular weight and renders
it useless for food applications.
Animal feeding studies which
began in the 1960s have demonstrated that
once poligeenan enters the blood stream in
large enough amounts, pre-cancerous lesions
begin to form, but these lesions have never
been observed in animals fed with foods
containing food-grade carrageenan.
Food-grade carrageenan passes
through the digestive system intact, much
like food fiber. In fact, food-grade carrageenan is a
combination of soluble and insoluble
nutritional fiber. Even if food-grade
carrageenan had exhibited toxicity in small
animals, one cannot make an assumption that
human biology will respond the same way,
especially when small laboratory animals are force fed amounts much
larger than a human would ever consume. This
would be like saying, “since chocolate is
toxic to dogs it must therefore be toxic to
humans”. And since when do vegans rely upon
animal research studies, the very
practice which we so vehemently oppose?
The Standard American Diet (SAD) consists of
a high percentage of processed, animal-based
foods loaded with preservatives, hormones,
artificial dyes and other chemicals. Making
such claims about food-grade carrageenan
without also ruling out these factors is
scientifically invalid. Negative effects can
be linked to just about any food or food
ingredient that is consumed in excess or by
individuals who are sensitive or allergic. This same ingredient
bashing has occurred with soy, gluten and
Consumer watchdogs have not conducted
any controlled laboratory experiments
themselves and are merely repeating inaccurate
conclusions based upon Dr. Tobacman's
flawed studies (which have been
repeatedly rejected by the scientific
community). This kind of fear-mongering can
be very damaging to the non-dairy food
movement. These individuals would do far more service
to consumers by researching their sources
thoroughly and presenting only what can be
substantiated by good science. Unfortunately
we live in an era of media frenzy that rewards controversy.
It should be noted that in over 70 years of
commercial use in processed foods, not a
single substantiated claim of an acute or
chronic disease has been documented as
arising from carrageenan consumption.
While it's true that some people
may be sensitive to food-grade carrageenan,
this is not due to toxicity but due to its
nature as a food fiber. Psyllium is also an
inert and non-toxic food fiber and ingestion
can cause bloating and cramping in sensitive
individuals. Consuming too many raw greens
can also cause intestinal distress in some
individuals but this doesn't make raw greens
the enemy. Stomach discomfort in sensitive
individuals is a far cry from the misguided
claims that food-grade carrageenan causes
intestinal lesions and is a proven
carcinogen. This has never been demonstrated
or proven in humans. If
this were true, federal law would require
labeling of any food item containing
carrageenan as potentially cancer-causing.
In a small percentage of the population, carrageenan
may provoke an allergic response,
although this can occur with many other food
substances, and does not infer toxicity but
rather a personal immune reaction to a
The food-grade carrageenan
used in the block and wheel cheeses in my cookbook is derived from a species of seaweed called
Kappaphycus alvarezii, hence the name "kappa carrageenan". Research has actually proven that
Kappaphycus alvarezii has
significant anti-cancer activity. Gigartina is another species of red seaweed
and is used in the extraction of lambda carrageenan,
in a similar manner as Irish Moss. Gigartina is wild harvested in various forms including
Gigartina Skottsbergii off the coast of Argentina and Chile, and
Gigartina Stellata from the coast of France.
Research has been done on Gigartina Skottsbergii
in treating the herpes simplex virus,
revealing that it actually stimulates an immune
response that can fight the virus and keep
it at bay.
I have researched both sides of the
carrageenan controversy thoroughly and with
an open mind. My opinion about carrageenan
safety is not influenced by any carrageenan
manufacturer because I don't work for any
such manufacturer. My opinion is based upon
the scientific data I have examined, but
more importantly by my own experience with
this ingredient. I've been consuming kappa
and iota carrageenan for several years now
in the course of developing my non-dairy
cheeses and plant-based marshmallows and I
have never experienced a single negative side
effect from its consumption. If I felt it
was dangerous, I wouldn't consume it.
The bottom line is that you’ll have to
decide for yourself who and what to believe,
and weigh the unproven health risks against
the culinary benefits of using carrageenan.
Only you can determine what's right and
wrong for your body. And don't just rely on
my opinion; do your own research - but keep
an open mind. You will find many opinions in
the media but you will not discover any
documentation of acute or chronic disease in
humans associated with this ingredient
because it doesn't exist. However, if you
still feel certain that you are sensitive to
carrageenan, or you are concerned about its
use, simply avoid the block and wheel cheeses and the
marshmallows in my cookbook. There are many
other non-dairy recipes to choose from.
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