Oats

Scientific Name(s): Avena sativa L.
Common Name(s): Avena (Spanish), Hafer (German), Ma-karasu-mugi (Japanese), Oats

Medically reviewed by Drugs.com. Last updated on Oct 4, 2021.

Clinical Overview

Use

Oats and oatmeal are used primarily as a food source. Use in celiac disease is debated. Benefits in dermatology, hypercholesterolemia, cardiovascular conditions, and diabetes mellitus remain controversial.

Dosing

The recommended intake of beta-glucan for reduction of cholesterol is 3 g/day, an amount found in approximately 90 g of oats.

Contraindications

None well documented.

Pregnancy/Lactation

US Food and Drug Administration (FDA) generally recognized as safe (GRAS) status when used as food. Avoid dosages higher than those found in food because safety and efficacy are unproven.

Interactions

Oat bran may decrease absorption of medications. There are reports of decreased absorption of HMG-CoA reductase inhibitors and iron with oat bran ingestion.

Adverse Reactions

Oat bran increases the bulk of stools and frequency of defecation, which may result in distention, flatulence, and perineal irritation. Oat sensitization and allergy have been described.

Toxicology

Data are lacking.

Scientific Family

• Gramineae

Botany

Oats grow as hardy annual grasses able to withstand poor soil conditions in which other crops are unable to thrive and are best adapted to areas with a cool, moist climate; Russia, the United States, Finland, and Poland are the world's major oat-producing countries. The plant grows to approximately 61 to 91 cm in height and has straight, hollow, blade-like leaves. The flowers contain 2 or 3 florets and are clustered at the top of the plant. Oat grain grows enclosed in 2 hulls that protect it during development. It contains 3 main structures: the bran, endosperm, and the germ containing embryonic structures that can grow into a new plant.1, 2, 3

History

Derived from wild grasses, the oat evolved into today's cultivated plant. The oldest known oat grains were found in Egyptian remains dating from approximately 2,000 BC. Scottish settlers introduced oats into North America in the early 17th century. Before being used as a food for humans, oats were used as a livestock feed in the form of grain, pasture, hay, or silage. Traditional medicinal uses of oats include the treatment of rheumatism, depression, chronic neurological pain, atonia of the bladder, and, externally, as a skin cleanser and emollient.2, 3

Chemistry

The dietary value of oats is very high compared with that of other cereals in the Gramineae family. Oats are a good source of soluble and insoluble fiber, manganese, selenium, phosphorous, tryptophan, thiamine, and vitamin E (mainly as alpha-tocopherol). The protein content is 15% to 20% higher than that of other cereal grains3 with approximately 10% consisting of storage proteins known as avenins.4 These proteins belong to the prolamin group and are related to the gluten found in wheat.4

Oat bran contains the soluble dietary fiber beta-glucan, a highly viscous soluble polysaccharide with a linear, unbranched structure composed of 4-O- and 3-O-linked beta-D-glucopyranosyl units. Other polysaccharides in oat include starch, araban, and xylan gums. Lipid content is high, especially in unsaturated triglycerides. Lipase, lipoxygenase, and superoxide dismutase are enzymes present in oats.3

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