Oat grass belongs to the grass family Poaceae, which includes various other species of grass such as wheat grass. Oat grass contains many nutrients, but you need to juice it or pulverize it in a powerful blender instead of simply eating it in order to metabolize it properly. Oat grass juice is not as popular as wheat grass juice, but it is nutritionally comparable. Oat grass juice is not widely available in smoothie shops or juice bars, but you can grow it and juice it at home without much expense or hassle. Consult with a nutritionist about the value of oat grass.

Oat grass or button grass is indigenous to the Mediterranean region and other parts of Europe. Oat grass is a common perennial with yellowish roots and shining stems that can grow to a height of 1.5 meters. Its wild form resembles wild oat, which explains its name. Oat grass is readily digested by cattle and other herbivores, but people lack the necessary enzymes to reduce it into absorbable nutrients. Raw oat grass will pass through your digestive track unmetabolized and may lead to bloating, diarrhea and other gastrointestinal symptoms.

Like most of the grasses from the Poaceae family, oat grass is a good source of many essential nutrients. Although not considered quite as nutritious as wheat grass, oat grass is still a good source of vitamins A, C, E and K, pantothenic acid, chlorophyll, lecithin, calcium, magnesium, potassium, iron and phosphorus, according to the book “Principles and Practice of Phytotherapy: Modern Herbal Medicine.” Furthermore, up to 30 percent of oat grass by weight is amino acids, which your body uses as the building blocks of proteins. However, unlike animal-derived sources, oat grass does not contain all the essential amino acids your body needs to synthesize complete proteins.

Since you cannot break down oat grass sufficiently by chewing and swallowing it, you will need to juice it. Oat grass and wheat grass require the use of specialized extractors that grind the grass up and extract its liquid. Alternatively, you can put oat grass in a powerful blender with some purified water and blend it for at least a minute or until the grass is completely pulverized. After pulverizing it, strain out the pulp by pouring the blender contents through a coffee filter or cheesecloth. You can consume oat grass juice on its own, although adding it to fresh orange or carrot juice may make it more palatable. Drink the oat grass juice slowly, ingesting only small amounts at a time until your body gets used to it.

You can purchase oat grass from a health food retailer either as seeds or live grass. Grass is easy to grow on your kitchen counter as long as there is sunlight, water and some soil. Once your grass grows to about 3 inches in height, cut a small handful of the blades off with a pair of sharp scissors. Trim the blades close to the roots, but don't pull up on the grass too hard. Oat grass can produce a second and even a third crop if you continue to water the grass. Subsequent crops are not usually as tender or as nutritious, according to the book “Herbs that Heal: Prescription for Herbal Healing,” but growing your own is the most cost effective way of making oat grass juice.