As the sun lowers toward the horizon, the yellow evening primrose prepares to bloom. For those who like to be enchanted by nature, gather a few friends at twilight, and wait for the blooms to open right before your eyes.
Evening primrose (Oenothera biennis) is native to North America, and is no relation to the English cowslip primrose (Primula veris). When evening primrose makes an appearance in the spring, it is a low-growing, basal rosette mass of leaves speckled with red. Throughout the summer, a very leafy reddish stem grows up from the center of the basal rosette, eventually reaching 3 to 5 feet.
The four-petaled, yellow flowers are unusual in that they flower at the end of a long pipe attached to a tube-shaped ovary, which will become the seed-containing fruit. Within the seeds of the evening primrose, a valuable oil is held. I eat the whole fruits to get the oil.
The entire plant is medicinal and edible. Currently, however, the seeds are the most used part of the plant. The oil found in evening primrose seeds is high in gamma-linoleic acid (GLA), an essential fatty acid (EFA) converted from linoleic acid by an enzyme called delta-6 desaturase.
Some people inherit an abnormality in EFA metabolism because they lack the delta-6-desaturase enzyme needed to convert linoleic acid to GLA.
This creates problems since GLA prevents proinflammatory eicosanoids, such as prostaglandins and leukotrienes, from becoming excessive and causing chronic illness conditions associated with inflammation, such as atopic eczema, asthma, rheumatoid arthritis, diabetes, heart disease, PMS and breast pain.
Since the 1980s, many clinical trials have shown efficacy in using evening primrose oil to treat atopic eczema, an escalating condition among children.
Trials reported that after administering evening primrose oil for four to eight weeks, the roughness, redness and itchiness of the skin was reduced. After discontinuing the evening primrose oil, the improvements remained, and the condition did not revert back to the pre-evening primrose state. Studies indicate evening primrose is less effective in people who have received frequent corticosteroid treatment.
Another interesting use of evening primrose oil is in the treatment of the neurological effects of alcoholism. Long-term alcohol use decreases linoleic acid in the blood, and creates a deficiency in EFAs, which isn’t good since EFAs provide the structure for nerve conduction. Alcohol use also blocks linoleic acid from converting to metabolites used in brain structure. Further, alcohol increases the manufacturing of proinflammatory prostaglandins.
Administering GLA and other EFAs has seemed to minimize the negative effects of alcohol.
Medicinally, Cherokee Indians have used an infusion, or tea, of evening primrose leaves to stimulate weight-loss. The Ojibwa soaked the entire evening primrose plant in warm water and applied it as a poultice to burns.
As food, Cherokees also cooked the spring leaves as vegetable greens, and boiled the fall roots like potatoes.
The Gosuite of Utah ate the tiny, oil-rich seeds, which is the most direct, and cheapest way of getting your GLA.
The above article originally appeared in the Urban Forager column of the Athens Banner-Herald on Sunday, September 5th, 2010.