Wheat grass is prepared by sprouting wheat seeds in water for 7-10 days before harvesting the leaves. Because the leaves are fibrous and difficult to digest, the juice from the leaves is extracted and consumed raw. Proponents of wheat grass believe that eating raw foods is more beneficial than eating cooked foods as the enzymes responsible for detoxifying the body are thought to be deactivated by cooking foods. Wheat grass juice is claimed to have several benefits, including neutralizing toxins and carcinogens in the body, preventing tooth decay, reducing high blood pressure, and aiding in the treatment and prevention of cancer and AIDS. It is also used to improve digestion, prevent hair from graying, for common colds, cough, rheumatic pain, chronic fatigue syndrome, ulcers, and skin conditions. However, none of these claims is supported by clinical studies.
Proponents of wheat grass equate chlorophyll to hemoglobin and believe that consumption of wheat grass can increase oxygenation in the body. This concept is not supported by current scientific understanding and there are no data from clinical trials to substantiate any of these claims.
Small studies of wheat grass juice indicate it may help reduce symptoms of distal ulcerative colitis (1), reduce the need for transfusions in patients with thalassemia major (6), and may decrease myelotoxicity in breast cancer patients undergoing chemotherapy (7). Larger studies are needed to evaluate these findings.
Nausea has been reported following consumption of wheat grass juice.
Because wheat grass juice is consumed raw, microbial contamination is also a concern.