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.
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. By 1940, cans of Schnabel's powdered grass were on sale in major drug stores throughout the United States and Canada
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. 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 (freshly squeezed with the water removed) is also available either spray-dried or freeze-dried.
Health claims 
||This section needs more medical references for verification or relies too heavily on primary sources. (September 2012)|
|Table 1. Nutrient comparison of 1 oz (28.35 g) of wheatgrass juice, broccoli and spinach.|
|Protein||860 mg||800 mg||810 mg|
|Beta-carotene||120 IU||177 IU||2658 IU|
|Vitamin E||880 mcg||220 mcg||580 mcg|
|Vitamin C||1 mg||25.3 mg||8 mg|
|Vitamin B12||0.30 mcg||0 mcg||0 mcg|
|Phosphorus||21 mg||19 mg||14 mg|
|Magnesium||8 mg||6 mg||22 mg|
|Calcium||7.2 mg||13 mg||28 mg|
|Iron||0.66 mg||0.21 mg||0.77 mg|
|Potassium||42 mg||90 mg||158 mg|
|Data on broccoli and spinach from USDA database. Data on Wheatgrass juice from indoor grown wheatgrass.|
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. There is some limited evidence of beneficial pharmacological effects from chlorophyll, though this does not necessarily apply to dietary chlorophyll.
There are a number of other small studies and pilots on the possible benefits of wheatgrass juice. According to Memorial Sloan Kettering Cancer Center, 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.
It has been claimed that wheatgrass helps blood flow, digestion and general detoxification of the body. 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. 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.
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.
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", a ratio of 1:23. 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. 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. Analysis of B12 content in wheatgrass has confirmed that it contains negligible amounts of the compound.
- Murphy, Sean (2002-10-13). "Wheatgrass, healthy for the body and the bank account". ABC Landline. Retrieved 2006-10-06.
- Meyerowitz, Steve (April 1999). "Nutrition in Grass". Wheatgrass Nature's Finest Medicine: The Complete Guide to Using Grass Foods & Juices to Revitalize Your Health (6th ed.). Book Publishing Company. p. 53. ISBN 1-878736-97-3.
- "Site Dedication and Construction Preliminaries, 1921-1923". Ahr-kc.com. Retrieved 2013-04-19.
- "USDA Nutrient Database". Retrieved 2007-11-06.
- de Vogel, Johan; Denise S. M. L. Jonker-Termont, Martijn B. Katan,and Roelof van der Meer (August 2005). "Natural Chlorophyll but Not Chlorophyllin Prevents Heme-Induced Cytotoxic and Hyperproliferative Effects in Rat Colon". J. Nutr. (The American Society for Nutritional Sciences) 135 (8): 1995–2000. PMID 16046728.
- Ferruzzia, Mario G.; Blakesleeb, Joshua (January 2007). "Digestion, absorption, and cancer preventative activity of dietary chlorophyll derivatives". Nutrition Research 27 (1): 1–12. doi:10.1016/j.nutres.2006.12.003.
- "Wheat grass | Memorial Sloan-Kettering Cancer Center". Mskcc.org. Retrieved 2013-04-19.
- Ben-Arye, E; Goldin, E; Wengrower, D; Stamper, A; Kohn, R; Berry, E (April 2002). "Wheat grass juice in the treatment of active distal ulcerative colitis: a randomized double-blind placebo-controlled trial". Scand J Gastroenterol 37 (4): 444–9. doi:10.1080/003655202317316088. PMID 11989836.
- Fahey, Jed W..; Katherine K. Stephenson, Albena T. Dinkova-Kostova, Patricia A. Egner, Thomas W. Kensler and Paul Talalay (2005). "Chlorophyll, chlorophyllin and related tetrapyrroles are significant inducers of mammalian phase 2 cytoprotective genes". Carcinogenesis 26 (7): 1247–55. doi:10.1093/carcin/bgi068. PMID 15774490.
- Marawaha, RK; Bansal, D; Kaur, S; Trehan, A; Wheatgrass Juice Reduces Transfusion Requirement in Patients with Thalassemia Major: A Pilot Study. Indian Pediatric 2004 Jul;41(7):716-20
- S. Mukhopadhyay; J. Basak; M. Kar; S. Mandal; A. Mukhopadhyay; Netaji Subhas; Chandra Bose; Cancer Research Institute, Kolkata, India; NRS Medical College, Kolkata, India; Central Institute for Research (Ayurveda), Kolkata, India. The Role of Iron Chelation Activity of Wheat Grass Juice in Patients with Myelodysplastic Syndrome. Journal of Clinical Oncology 27:15s, 2009 (suppl; abstr 7012) 2009 ASCO Annual Meeting. Presenter: Soma Mukhopadhyay, PhD.
- Bar-Sela, Gil; Tsalic, Medy; Fried, Getta; Goldberg, Hadassah. Wheat Grass Juice May Improve Hematological Toxicity Related to Chemotherapy in Breast Cancer Patients: A Pilot Study. Nutrition and Cancer 2007, Vol. 58, No. 1, Pages 43-48.
- Alitheen NB, Oon CL, Keong YS, Chuan TK, Li HK, Yong HW."Cytotoxic effects of commercial wheatgrass and fiber towards human acute promyelocytic leukemia cells (HL60)." Pak J Pharm Sci. 2011 Jul;24(3):243-50
- Melina, Vesanto, MS, RD & Davis, Brenda, RD: "The New Becoming Vegetarian", page 186-187. Healthy Living Publications, 2003.
- "Nutrition Facts and Analysis for wheat grass". Nutritiondata.self.com. Retrieved 2013-04-19.
- Wheatgrass Juice: Is the magical mystery juice all it's blended up to be? Skeptoid: Critical Analysis of Pop Phenomena November 6, 2009
- Wheatgrass Juice & Folk Medicine Michael Shermer, Scientific American, 299, 42 (2008)