Principal Proposed Uses
- "Cleansing the Body"
- General Health Improvement
- Ulcerative Colitis
Grains such as wheat and barley are ordinarily consumed in their mature state – once their seeds have fully matured. However, use of the deep green, immature forms of these plants has been advocated for health promotion. Wheat grass juice is one of these "green foods." It was popularized in the 1960's by Ann Wigmore. She claimed that use of wheat grass juice had cured her of the disease ulcerative colitis; furthermore, when she gave it to her neighbors, their health improved too. She went on to become a major figure in the natural health movement.
Since wheat grass, a succession of "green drinks" have become popular for "cleansing" the body and improving overall health. "Barley magma" and blue-green algae both fall within this tradition.
What Is Wheat Grass Used for Today?
There is no question that wheat grass juice is a nutritive food, containing numerous amino acids, vitamins and minerals. However, besides known human nutrients, wheat grass also contains a number of other substances that proponents claim provide benefit.
For example, wheat grass, like all leafy plant products, contains chlorophyll, the substance used by plants to create glucose from carbon dioxide and light energy. Chemically purified chlorophyll became a popular health food supplement in the 1960s, when it was promoted as a cure for many diseases. Chlorophyll's central role in the metabolism of plants was somehow supposed to suggest benefit for people. However, animals no more have an obvious use for chlorophyll than plants have for hemoglobin (the vital substance in red blood cells). It is certainly possible that chlorophyll could, by chemical accident, offer benefit for animals, but there is no meaningful evidence to indicate that it actually does. .
Wheat grass also contains superoxide dismutase (SOD) , a substance used by the body as part of its natural antioxidant defense system. Superoxide dismutase is very poorly absorbed by mouth, and it is unlikely that people who consume wheat grass juice receive a meaningful quantity of this substance. Furthermore, the benefit of antioxidants per se has been cast in doubt by the failure of such supplements as vitamin E and beta-carotene to prove effective when tested in enormous double-blind studies.
Proponents of wheat grass also point to a constituent called P4D1 as another source of benefit. However, while P4D1 has shown interesting properties in test-tube studies , there is no real evidence that it offers any benefit.
The only scientifically reliable way to determine whether a medical treatment truly offers medical benefits is to test it in double-blind, placebo-controlled studies . Two such studies have been reported for wheat grass. One found benefit but was seriously flawed; the other failed to find benefit.
This study is interesting, as it tests the initial use of wheat grass popularized by Ann Wigmore. However, the study suffers from two major limitations. One is that it was quite small, limiting the statistical validity of the results. The other is that wheat grass juice is extremely bitter, and therefore it seems unlikely on the face of it that participants and doctors did not know who was getting the wheat grass juice and who was getting the placebo. Indeed, when researchers polled the participants, a majority of those given wheat grass juice were aware of it. Such "unblinding" substantially invalidates a study; to learn why, see Why Does This Database Depend on Double-Blind Studies .
In promotional literature, wheat grass juice is additionally advocated for numerous other conditions, including cancer, arthritis, allergies, fatigue, diabetes, etc. However, there is no meaningful scientific evidence to support these uses.
Wheat grass juice is believed to be safe. However, comprehensive safety studies have not been performed. Maximum safe doses in pregnant or nursing women, young children, or people with severe liver or kidney disease have not been reported.
- Reviewer: EBSCO CAM Review Board
- Review Date: 07/2012 -
- Update Date: 07/25/2012 -