The soluble fiber portion contains the richest source of beta-glucans compared to any other grain; these can aid immune function.

Barley also contains B vitamins, iron, magnesium, zinc, phosphorus, and copper, and is one of the richest sources of chromium, which is important in maintaining blood glucose levels.

Barley is also rich in antioxidants and contains a high concentration of tocols and tocotrienols, oils that help reduce the risk of cancer and heart disease.

[citation needed] Barley has been cited as a possible food to increase tryptophan, and thus serotonin in the body.

[2] Ibn Sina, in his 11th-century work The Canon of Medicine, wrote of the healing effects of barley water, soup and broth for fevers.