Wheatgrass
From Wikipedia, the free encyclopedia
Wheatgrass is a food prepared from the cotyledons
of the common wheat plant, Triticum aestivum. It is sold either as a juice or powder concentrate.
Wheatgrass differs from wheat malt in that it is served freeze-dried
or fresh, while wheat malt is convectively
dried.
Wheatgrass is also allowed to grow longer than malt is. It provides chlorophyll,
amino acids,
minerals,
vitamins,
and enzymes.
Claims about the health benefits of wheatgrass range from providing
supplemental nutrition to having unique curative properties, though few if any
have been scientifically proven. Some consumers grow and juice wheatgrass in
their homes. It is often available in juice bars,
alone or in mixed fruit or vegetable drinks. It is also available in many
health food stores as fresh produce,
tablets, frozen juice and powder. Wheatgrass contains no wheat gluten.
History
The consumption of wheatgrass in the
Western world began in the 1930s as a result of experiments conducted by Charles F. Schnabel in his attempts to popularize the plant.[1]
By 1940, cans of Schnabel's powdered grass were on sale in major drug stores
throughout the United States and Canada[2]
Cultivation
Schnabel's research was conducted
with wheatgrass grown outdoors in Kansas. His wheatgrass required 200 days
of slow growth, through the winter and early spring, when it was harvested at
the jointing stage. He
claimed that at this stage the plant reached its peak nutritional
value; after jointing, concentrations of
chlorophyll, protein, and vitamins decline sharply.[3]
Harvested grass was dehydrated and made into powders and tablets for human and
animal consumption. Wheatgrass grown indoors in trays for ten days contains
similar nutritional content. Wheatgrass grown outdoors is harvested, dehydrated at a low temperature and sold in tablet and powdered concentrates. Wheat grass
juice powder is also available either spray-dried
or freeze-dried.
Health
claims
Proponents of wheatgrass make many
claims for its health properties, ranging from promotion of general well-being
to cancer prevention. These claims have not been substantiated in the scientific
literature.[1]
There is some limited evidence of beneficial pharmacological effects from
chlorophyll, though this does not necessarily apply to dietary chlorophyll.[5][6]
There are a number of other small
studies and pilots on the possible benefits of wheatgrass juice. According to
Memorial Sloan Kettering Cancer Center,[7]
there may be a need for further study of wheatgrass therapy for ulcerative
collitis; they cite a small pilot study which showed regular wheatgrass juice
therapy significantly reduced rectal bleeding and overall disease activity.[8]
It has been claimed that wheatgrass
helps blood flow, digestion and general detoxification
of the body.[9]
These claims have not been reliably substantiated, or are no different from
similar vegetables. However, in one pilot study of children with thalassemia
(a hereditary form of anemia which often requires blood transfusions), of the
patients who were given 100 ml of wheatgrass juice daily, half showed
reduced need for transfusions. No adverse effects were observed.[10]
Another small study of transfusion-dependent patients suffering from myelodysplastic
syndrome responded similarly to wheatgrass
therapy; that is, the intervals between needed transfusions were increased. In
addition, the chelation effect (removal of heavy metals from the blood) was
studied for the same patients; the wheatgrass therapy showed a significant iron
chelation effect.[11]
In another pilot, which was not placebo
controlled, breast cancer patients who drank
wheatgrass juice daily showed a decreased need for blood- and bone
marrow-building medications during chemotherapy, without diminishing the
effects of the therapy.[12]
Nutritional
content
Wheatgrass proponent Schnabel claimed in the 1940s that "fifteen pounds
of wheatgrass is equal in overall nutritional value to 350 pounds of ordinary
garden vegetables",[2]
a ratio of 1:23.[3]
Despite claims of vitamin and mineral content disproportional to other
vegetables, the nutrient content of wheatgrass juice is roughly equivalent to
that of common vegetables (see table 1).
Wheatgrass is also claimed to be
superior to other vegetables in its content of vitamin B12, a vital nutrient.[citation needed] Contrary to popular belief, B12 is not contained
within wheat grass or any vegetable, rather it is a byproduct
of the microorganisms living on plants.[14]
Analysis of B12 content in wheatgrass has confirmed that it contains
negligible amounts of the compound.[15]
The entire wiki link on this subject can be found at:
http://en.wikipedia.org/wiki/Wheatgrass
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