About.com states that barley grass, often used in juicing, has been proposed to treat ailments such as high blood pressure, insomnia and diabetes. It has also been said to slow the aging process and boost energy. There are studies showing its positive effects on fibromyalgia and high cholesterol.
About.com describes a study done in 2001 that discovered that a vegetarian diet along with a barley grass juice product reduced fibromyalgia symptoms and improved flexibility. Another study showed that a diet heavily composed of fruits and vegetables along with a barley grass powder supplement reduced the cholesterol count of the study participants.