Zeewier wordt ook gebruikt als voedsel, al
is het in Europa veel minder bekend dan in landen als Japan. Het kan als groente worden
gegeten, maar ook worden gebruikt als decoratie. In sushi worden strookjes zeewier
gebruikt om de verschillende rijst- en visingrediėnten bij elkaar te houden door een
smalle strook om het hapje te wikkelen. Japanse zoutjes, een soort rijstcrackers of
rijstzoutjes, worden vaak ook met wat zeewier bedekt om ze een pittige smaak te geven.
Zeewier is rijk aan mineralen zoals jodium en calcium en spore-elementen. Afhankelijk van
de soort bevat het tevens vitaminen als vitamine C en E. Bruin zeewier bevat ongeveer
5-10%, rood en groen zeewier ongeveer 10-30% eiwit. Een deel van zeewier wordt niet door
het lichaam afgebroken en kan als voedingsvezel worden gezien.
Zeewier helpt ook radioactieve isotopen uit
het lichaam te verwijderen. Het gebruik van minstens enkele malen per week van dit zeewier
als condiment als ook als groente (zodat je ongeveer een halve kop er van binnenkrijgt) is
noodzakelijk zodat er chelatering plaatsvindt. Dus, buiten de universele vervuiling en het
leegvissen van onze visbestanden, zouden we rustig van onze vissen kunnen genieten!
Rijke hoeveelheid jodium in zeegroente
helpt tegen groei- en ontwikkelingsstoornis. Ook buiten de kring van veganisten en
macrobioten staat zeewier steeds vaker op het menu. Een gezonde ontwikkeling, zeggen
voedseldeskundigen.
David Wolfe discusses the importance of
natures original superfood: Sea Veggies, and Glyconutrients.
Mike
Irish seaweed
Their are many different types with
different benefits but most contain iron, calcium, vitamin A,E,K, B-complex
(B1,B2,B3,B5,B6,B12) & folic acid. Essential fatty acids, nucleic acids like RNA and
DNA, phyto-chemicals as carotenoids. Rich in fiber and natural polysaccharides. This
unique mixture of vitamins, minerals/trace elements, anti-oxidants and phyto-nutrients is
not common in land plants.
Seaweed draws an extraordinary wealth of
mineral elements from the sea that can account for up to 36% of its dry mass. The mineral
macronutrients include sodium, calcium, magnesium, potassium, chlorine, sulfur and
phosphorus; the micronutrients include iodine, iron, zinc, copper, selenium, molybdenum,
fluoride, manganese, boron, nickel and cobalt. Seaweed has such a large proportion of
iodine compared to dietary minimum requirements, that it is primarily known as a source of
this nutrient. The highest iodine content is found in brown algae, with dry kelp ranging
from 1500-8000 ppm (parts per million) and dry rockweed (Fucus) from 500-1000 ppm. In most
instances, red and green algae have lower contents, about 100-300 ppm in dried seaweeds,
but remain high in comparison to any land plants. Daily adult requirements, currently
recommended at 150 µg/day, could be covered by very small quantities of seaweed. Just one
gram of dried brown algae provides from 500-8,000 µg of iodine and even the green and red
algae (such as the purple nori that is used in Japanese cuisine) provides 100-300 µg in a
single gram.
New studies conducted at Hokkaido
University have found that a compound in wakame known as fucoxanthin can help burn fatty
tissue. Studies in mice have shown that fucoxanthin induces expression of the fat-burning
protein UCP1 that accumulates in fat tissue around the internal organs. Expression of UCP1
protein was significantly increased in mice fed fucoxanthin. Wakame is also used in
topical beauty treatments. In Oriental medicine it has been used for blood purification,
intestinal strength, skin, hair, reproductive organs and menstrual regularity
Video - Perspectives on Ocean
Science: Survival in the Sea - Biochemical Warfare
How do seemingly harmless invertebrates and
seaweeds defend themselves against predators? How do they ward off competitors for space
and ... all » resources, or stop deadly infection by millions of marine microbes in
seawater? Join Scripps Institutions' Melany Puglisi and find out the answer to these and
other compelling questions about microbial pathogens in the marine environment Series:
Perspectives on Ocean Science
Researchers have discovered that marine
seaweeds have a remarkable and previously unknown capacity to detoxify serious organic
pollutants such as TNT or polycyclic aromatic hydrocarbons, and they may therefore be able
to play an important role in protecting the ecological health of marine life.The studies,
conducted by scientists from the College of Engineering at Oregon State University and the
Marine Science Center at Northeastern University, were presented today at the annual
meeting of the American Association for the Advancement of Science.
The findings may have important
implications for seafood safety, since some of the marine organisms most at risk from
these toxins are marine invertebrates such as clams, shrimp, oysters or crab that tend to
"bioaccumulate" them. One possibility, the researchers say, might be to plant
appropriate seaweeds as a protective buffer around areas being used in aquaculture.
"We found that certain red seaweeds
had an intrinsic ability to detoxify TNT that was 5-10 times faster than any known
terrestrial plant," said Greg Rorrer, a professor of chemical engineering at OSU.
"Marine seaweeds have a more efficient uptake mechanism than even terrestrial aquatic
plants to at least neutralize organic pollutants."
The researchers call this process
"phycoremediation," derived from phykos, a Greek word for seaweed. The studies,
which are supported by the Office of Naval Research and the Oregon Sea Grant Program, are
of particular interest in the case of trinitrotoluene, or TNT, because of unexploded bombs
or military shells found in some places around the world's oceans. There is a general
concern these shells could potentially corrode.
"It's important to know how corals,
fisheries and plant life might respond to exposure to TNT or other toxins," Rorrer
said. The study is looking at not just TNT, which is commonly found in munitions, but at
polycyclic aromatic hydrocarbons, such as naphthalene, benzopyrene and other PAHs that are
sometimes associated with the use of motorcraft or other causes. Ongoing studies found
that marine seaweeds processed toxins to a much less harmful form, and in a way that did
not appear to harm the seaweed. The biochemistry involved, they say, is similar to that
found in many land organisms, but more powerful and effective. Until now, the capability
of marine seaweeds to deal with these toxins had never before been demonstrated.
It's unclear yet whether similar plants can
be identified, the researchers said, that will perform this function in terrestrial fresh
waters, such as streams or lakes. These research outcomes should lead to the development
of new bioremediation technologies that use seaweed in engineered systems to remove
organic contaminants from the marine environment, the scientists said. Studies to create
genetically engineered seaweeds that perform these functions even better are also
promising, the researchers said.
Seaweed could make junk food
healthier
Junk food could be made healthier by adding
an extract of an exotic type of seaweed, say British scientists. The highly-fibrous
seaweed extract, alginate, could be used to increase the fibre content of cakes, burgers
and other types of food which usually contain large amounts of fat and a low degree of
healthy nutrients, say the team.
Scientists at the University of Newcastle
upon Tyne publish their findings in the academic journal Critical Reviews in Food Science
and Nutrition, in a paper detailing alginate's many benefits to the body. They believe it
will be a valuable weapon in the international battle against obesity, diabetes and heart
disease and diseases such as bowel cancer. The research paper examines the properties of a
brown-coloured seaweed called Lessonia and Laminaria, found in the Far East, South America
and parts of Norway and Scotland. The seaweed is processed in the laboratory to produce
the extract, alginate, a carbohydrate compound which is a tasteless and odourless
off-white coloured powder.
The paper shows that alginate has been
proved to strengthen mucus, the body's natural protection of the gut wall, can slow
digestion down, and can slow the uptake of nutrients in the body. Moreover, alginate is
high in fibre and has been proved to be palatable and safe, and as such is already in
widespread use by the food industry as a gelling agent, to reconstitute powdered foods,
and to thicken the frothy head of premium lagers.
Studies have shown that eating high-fibre
diets can help reduce the incidence of diseases such as bowel cancer. Good sources of
fibre are fruit and vegetables, brown bread and cereals like bran flakes. One of the
research team, Professor Jeff Pearson, of Newcastle University's Institute for Cell and
Molecular Biosciences, said: "We're just not eating enough fibre, yet we need this to
keep us healthy. The problem is that a lot of people don't enjoy many of the foods that
are high in fibre, like fruit and vegetables, yet to consume the recommended daily amount
of fibre they would have to eat a lot of these types of foods.
"We believe it's hard to change
people's habits and that the most practical solution is to improve the food they do eat.
With a burger, for example, you would simply remove some of the fat and replace it with
the seaweed extract, which is an entirely natural product from a sustainable resource.
You'd have a healthier burger and it's unlikely to taste any different. "This
compound can also be added to any number of foods, such as synthetic creams and yoghurts.
With pork pies, one of my favourite foods, it could replace the gelatine which usually
covers the meat, as the seaweed extract has gelling properties too." Prof Pearson,
who has already made loaves of bread containing the seaweed extract which passed the taste
test with colleagues, added: "Bread is probably the best vehicle to reach the general
population because most people eat it. Adding the seaweed extract could quadruple the
amount of fibre in white bread."
New study finds kelp can reduce
level of hormone related to breast cancer risk
Berkeley -- A type of vegetation that can
often be found washed ashore on beaches may soon emerge as a new player in the field of
cancer-fighting foods. A new study led by researchers at the University of California,
Berkeley, has found that a diet containing kelp seaweed lowered levels of the potent sex
hormone estradiol in rats, and raised hopes that it might decrease the risk of
estrogen-dependent diseases such as breast cancer in humans. "This study opens up a
new avenue for research leading to cancer preventive agents," said Martyn Smith, UC
Berkeley professor of environmental health sciences and co-author of the study. "Kelp
is a little studied nutrient, but there's good reason to look at it more closely."
Prior studies have shown that Japanese women have longer menstrual cycles and lower serum
estradiol levels than their Western counterparts, which researchers say may contribute to
their lower rates of breast, endometrial and ovarian cancers. Scientists have been
searching Asian diets for clues to the lower rates of cancer, with the lion's share of
attention being given to soy.
"Brown kelp seaweed makes up more than
10 percent of the Japanese diet," said Christine Skibola, assistant research
toxicologist at UC Berkeley's School of Public Health and lead author of the study.
"Soy has gotten most of the attention, but our study suggests that kelp may also
contribute to these reduced cancer rates among Japanese women." The researchers say
that the type of kelp used in this study, bladderwrack seaweed (Fucus vesiculosus), is
closely related to wakame and kombu, the brown seaweeds that are most commonly consumed in
Japan. Bladderwrack seaweed is the primary form of kelp sold in the United States. They
say these study results support the need for more research on wakame and kombu. Skibola
said she began the animal study after obtaining encouraging results from earlier case
studies of women with highly irregular menstrual cycles.
"The most profound thing I found was
that two women with endometriosis and a lot of menstrual irregularities experienced
significant improvement in their symptoms after three months of taking 700 milligrams of
seaweed capsules per day," said Skibola. "It reduced much of the pain associated
with endometriosis and significantly lengthened the total number of days of their
menstrual cycles. In one of these women with high estrogen levels, I also saw a drop in
blood estradiol levels from 600 picograms per milliliter down to 90 picograms per
milliliter after she included kelp in her diet. That led me to believe it was worth doing
further controlled studies on kelp."
For the new study, the researchers randomly
divided 24 female rats into three groups. One group was fed a high daily dose of 70
milligrams of dried, powdered kelp for four weeks, while a second group was fed a low
daily dose of 35 milligrams. Both groups were compared with a third control group of rats
that did not receive kelp. To ensure that all the kelp was eaten, Skibola and study
co-author John Curry, a UC Berkeley post-doctoral fellow in molecular and cell biology,
sprinkled the powdered kelp onto apple wedges, one of the rats' favorite foods. The
researchers said the experimental doses of kelp consumed by the rats were roughly
equivalent to the amount of brown seaweed eaten by people in Japan.
Skibola and Curry took on the task of
taking daily vaginal swabs to monitor the rats' menstrual cycles. The researchers found
that the rats' estrous cycles increased from an average of 4.3 to 5.4 days for the low
dose kelp group, and to 5.9 days for the high dose kelp group. Overall, dietary kelp
resulted in a 37 percent increase in the length of the rat estrous cycle. Studies in
humans have linked longer menstrual cycle lengths to lower risk of breast, ovarian and
endometrial cancers. "If you have longer cycles, you actually have fewer periods over
a lifetime, which means less time is spent overall in the phases where hormone levels and
breast and endometrial cell proliferation are at their highest," said Skibola. During
the early part of a woman's menstrual cycle, estradiol levels remain relatively constant.
Almost halfway through the cycle, estradiol levels surge, peaking just before ovulation.
These cyclic periods of high estrogen, which continues over a span of about 40 years from
puberty to menopause, stimulates the division of breast cells that already have DNA
mutations, as well as increases the chances of developing new mutations, factors that may
increase one's risk of breast cancer.
To test the impact of dietary kelp on
estradiol levels, researchers took baseline blood samples from 19 rats immediately before
their low dose diet of kelp began. After just two weeks of eating 35 milligrams a day,
estradiol levels were reduced from an average of 48.9 nanograms per liter to 40.2
nanograms per liter. After four weeks, estradiol levels dropped further to 36.7 nanograms
per liter. In a separate test of human ovarian cell cultures, conducted in collaboration
with colleagues at UC Davis, dosing with kelp extract led to a 23 to 35 percent decrease
in estradiol levels.
"One possibility is that the kelp may
be acting as an estrogen antagonist by preventing estradiol from binding with its estrogen
receptors," said Skibola. "Our next step is to try to isolate the active
compound in kelp that is having this hormone-modulating effect."
She noted that seaweed contains several
complex compounds, including polyphenols that are considered antioxidants. Kelp
supplements are available in health food stores since they are taken as a source of iodine
by people with thyroid conditions. However, the researchers caution against a run on kelp
because of these early results, particularly because kelp can accumulate heavy metals.
"People should be careful about excessive kelp intake," said Skibola. "The
high levels of iodine and the low levels of heavy metals contained in kelp means that it's
not recommended for people who are pregnant, nursing, or who have hyperthyroid
conditions." The researchers say they are working to isolate the active compounds in
kelp that affect estradiol levels to avoid the possible toxicity of the iodine and metals.
They say there is hope that kelp could eventually be used as an anti-estrogen in the
treatment of hormone-dependent cancers if further tests demonstrate its effectiveness in
humans. "It's a study that points to the need for more studies," said Smith, the
study co-author. "But this certainly suggests that there are other elements of the
Asian diet beyond soy that should be explored." Other study co-authors are Catherine
VandeVoort, a UC Davis associate adjunct professor at the California National Primate
Research Center, and Alan Conley, UC Davis associate professor of veterinary medicine.
Chemicals in brown algae may
protect against skin cancer
Substances extracted from a marine seaweed
may protect against skin cancer caused by too much sun, new research suggests. The animal
study indicates that chemicals called brown algae polyphenols (BAPs), which are found in a
type of brown marine seaweed, might protect against skin cancers caused by ultraviolet B
(UVB) radiation.
UVB radiation in sunlight is thought
responsible for 90 percent of the estimated 1.3 million cases of non-melanoma skin cancer
diagnosed in the United States annually. Researchers applied the BAPs to the skin of
hairless mice and fed it to the animals in their diet. In both cases, the substances
reduced the number of skin tumors by up to 60 percent and their size by up to 43 percent.
They also reduced inflammation. The study, led by researchers at the Ohio State University
Comprehensive Cancer Center, is published in the Dec. 15 issue of the International
Journal of Cancer. "These compounds seemed to be dramatically effective at fairly low
doses both orally and topically," says principal investigator Gary D. Stoner,
professor emeritus of internal medicine and a cancer chemoprevention researcher.
"These findings suggest that, even
when eaten, these compounds get to skin cells and neutralize the cancer-causing oxygen
radicals that are produced by UV exposure." Laboratory research has shown that BAPs
are strong antioxidants and may have anticancer properties. For this study, Stoner and his
collaborators used a strain of hairless mice that are particularly susceptible to
UVB-induced skin cancer. Nine experimental groups were used, each with 20 mice. In two
groups, BAPs were applied to the skin in concentrations of 3 milligrams or 6 milligrams in
a mild solvent. In two other groups, BAPs made up 0.1 percent or 0.5 percent of the diet.
A group of untreated control mice was also exposed to UVB. The remaining groups were
additional controls: Two were fed the standard diet with and without UV exposure, and two
had the BAP solvent applied to the skin with and without UV exposure. The mice received
the BAPs for two weeks before UVB exposure began, followed by 24 weeks of increasing UVB
exposure according to a standardized schedule. The researchers then counted the number of
tumors in the treatment and control groups and calculated their size.
Animals exposed only to UVB developed an
average of 8.5 skin tumors. The animals fed the lower and the higher dose of BAPs
developed an average of 4.7 and 3.7 tumors respectively. Of those given the topical
treatment, the lower and higher doses developed 3.4 and 4.6 tumors respectively. In terms
of tumor volume, the animals fed BAPs at the lower and higher doses had tumors that were
34 percent and 40 percent smaller than those in animals exposed to UVB alone. Of those
given the topical treatment, the lower and higher dose animals had tumors that were 27
percent to 43 percent smaller than animals exposed to UVB alone. In addition, the
researchers compared the groups for skin levels of the enzyme cyclooxygenase-2 (COX-2) and
of the hormone-like substance prostaglandin E2, both of which are strong indicators of
inflammation, and for cell proliferation rates. Animals treated with BAPs showed lower
levels of both COX-2 and prostaglandin E2.
The researchers found that the dietary BAPs
reduced COX-2 activity by 74-82 percent, and that the topical BAPs reduced it by 66-82
percent. They also measured lower rates of cell proliferation in BAP-treated animals.
"Both the oral and topical BAP treatment reduced COX-2 and prostaglandin E2 cell
proliferation levels in the skin," Stoner says, "which corresponds with fewer
tumors and small tumors in the treated animals."
