The evening primrose often grows in this country at the edges of the road, in gardens or along railway tracks. Its seeds provide evening primrose oil. This contains quite large amounts of the unsaturated fatty acids linoleic acid and gamma-linolenic acid. This makes the oil one of the few sources of these fatty acids. In the case of skin diseases, taking these fatty acids can have positive effects. Find out more about the medicinal plant, the oil extracted from its seeds and the effect of evening primrose oil on the skin in this article.
Occurrence and distribution of the evening primrose
The common evening primrose (Oenothera biennis L.) belongs to the family of evening primroses (Oenothera). It first made their way to Europe as an ornamental plant in the 17th century. Over time, it was also planted more and more frequently in kitchen gardens. All parts of the plant are edible, from the root to the leaves and flowers to the seeds. The evening primrose roots and leaves were once part of the diet for many people. The plant is originally native to North America. In this country, it is actually a neophyte, i.e. a newly naturalised plant that was not originally native here. It is now so common that it is often mistaken for a native species.
Oenothera biennis prefers to grow in a sunny location on dry, nutrient-poor and chalky soils. It is, therefore, one of the so-called ruderal plants that thrive on gravel, along railway lines, at rubble sites or at road edges.
Appearance of the evening primrose
The common evening primrose is a biennial plant. This is also indicated by the species name "biennis" (Latin for biennial). In the first year it forms a flat leaf rosette and sends a long tap root underground up to 1.5 metres deep into the soil. In the second year, a stem with leaves up to 20 centimetres long grows from the rosette. In the second year of growth, the plant reaches heights of one to two metres, depending on the location.
The flowering period in this country extends from the beginning of June to September. The flowers are bright yellow and about four centimetres tall. The evening primrose takes its name from the flowers that open in the evening and attract moths for pollination. After flowering, numerous capsule fruits form on the plant. Each capsule contains up to 200 small seeds, from which the evening primrose oil that is used medically is extracted.
Ingredients and effect of evening primrose oil
Evening primrose oil contains large amounts of unsaturated fatty acids. These play an important role in the body. They are components of each cell. Some fatty acids have an anti-inflammatory effect, while others are precursors of hormones or are important for cell division. That is why every person needs essential fatty acids every day. The body cannot form these itself. They must be supplied from the outside.
The reason for using evening primrose oil capsules lies in their high content of a very special fatty acid: gamma-linolenic acid (GLA for short). It is one of the series of omega-6 fatty acids and has a range of positive effects on the skin. In the human body, gamma-linolenic acid can also be formed from the essential unsaturated fatty acid linoleic acid. Evening primrose oil contains up to 75 percent linoleic acid and 12 percent GLA. This makes evening primrose oil, along with borage oil, one of the few sources of gamma-linolenic acid. In addition to the omega-6 fatty acids, the oil also contains vitamin E, which has an antioxidant effect and can trap free radicals.
Evening primrose oil as a medicine
Most often, the pure oil of evening primrose is taken in the form of capsules to relieve itching and soothe dry skin. The mechanism of action of evening primrose oil has not yet been conclusively clarified. The effect could be due to the fact that the skin can store more moisture when there is a sufficient supply of gamma-linolenic acid. Gamma-linolenic acid is also said to prevent or reduce inflammation. When taken as a capsule, it should be used daily over a longish period of time until the effect on the skin ceases.
This is general information. For individual advice, please contact a specialist.