Barley is considered to be the first cereal grain cultivated by humans. Its medicinal and food use dates back to 7000 BC. Crop reports on barley date back to 2440 BC, and the Chinese were cultivating barley circa 2000 BC. Since biblical times, ancient Asian and Middle Eastern cultures reportedly included young wheat and barley grass plants in their diets. Historically, the plant species was used in the treatment of skin, liver, blood, and GI disorders. Ancient Greeks used the mucilage derived from the cereal to treat GI inflammations. Gladiators ate barley for strength and stamina. The Roman physician Pliny used barley as part of a ritualized cure for boils.
In 1940, it was explained how the vitamins, minerals, and protein in the cereal grasses are essential to animals and humans. A dehydrated preparation of cereal grass called “cerophyl” was approved as an “accepted food” by the Council of Foods of the American Medical Association in 1939. Later, synthetic nutrients were added to a number of foods, and multivitamins gained popularity. The juice of barley grass contains beta carotene, vitamins B1, B2, B6, B12, pantothenic acid, and folic acid. Minerals present include potassium, calcium, iron, phosphorus, and magnesium. Other constituents are chlorophyll, amino acids, protein, fiber, and enzymes. Cobalamin or vitamin B12 deficiency may be avoided in vegetarian diets by supplementation with dehydrated barley grass juice.
Barley leaf extract has the ability to scavenge free radicals. Reactive oxygen species have been shown to play an important part in mediating the production of pro-inflammatory cytokines and can be instrumental in the pathogenesis of diseases such as rheumatoid synovitis, arthritis, and gout. Animal data shows an increased production of oxygen-free radicals with barley leaf extract added to the diet. Clinical studies show blood levels of oxygen-free radicals were reduced by supplementation with 15 g/day barley leaf extract in patients with type 2 diabetes mellitus. Similar results were noted in nondiabetic, hyperlipidemic patients. More clinical studies are needed to show the extent of benefits in humans.
Barley grass extracts protect human tissue cells against carcinogens. The mechanism of action is unknown but may be associated with the plant's antioxidant activity or its chlorophyll content. It has been suggested that complexes may be formed between the carcinogen and the chlorophyll that may inactivate the carcinogen. In addition, antioxidants, including superoxide dismutase, found in high concentrations in green barley juice protect against radiation and free radicals. Research reveals no clinical data regarding the use of barley grass for cancer-preventive properties.
Cholesterol-lowering effects have been attributed to the beta-sitosterol components, in part. Beta-sitosterol is thought to act by inhibiting the intestinal absorption of cholesterol and accelerating its catabolism to bile acid. Preliminary animal and clinical data show that total cholesterol and LDL cholesterol levels were lowered. HCL cholesterol levels were increased. More clinical studies are needed to be conclusive.