Oenothera is a genus of about 125 species of annual, biennial and perennial herbs. It is the type genus of the family Onagraceae. They are known as evening primroses, and are native to North and South America (i.e. Blackfoot tribe).

GoldBamboo

... Oil pressed from the seeds of evening primrose plants contains large amounts of polyunsaturated omega-6 fatty acids. These are among the essential fatty acids (EFAs) needed by the body to regulate activities such as heart function, insulin utilization, and mood balance. The body cannot produce EFAs, so they must be eaten in the diet or taken as supplements. Estimates are that between 65% and 80% of evening primrose oil is composed of the EFA linoleic acid and between 2% and 15% is another EFA, gamma-linolenic acid (GLA). Linoleic acid may play a role in the ways that the body utilizes insulin, maintains weight, and resists cancer and heart disease. Linoleic acid is converted into GLA when it is digested in the body. GLA is believed to interrupt the body''s production of chemicals that initiate and maintain inflammation. Therefore, evening primrose oil is often used to treat inflammatory conditions such as rheumatoid arthritis (RA) and asthma. In multiple animal and human studies, taking evening primrose oil reduced inflammation, joint damage, and pain from RA. However, relief took up to 6 months to reach full effectiveness for some individual study participants. Results from other studies were inconclusive, with many finding little or no effectiveness for evening primrose oil in asthma and other inflammatory conditions. Some very early findings from other studies suggest that evening primrose oil may be useful in treating chronic fatigue syndrome, but more research is needed before evening primrose oil can be recommended for that condition. ...
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?Oenothera biennis Scientific classification Kingdom: Plantae ...
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