Here are some information about evening primrose oil. Hope it can be beneficail for you.

Introduction:

Evening primrose oil, also known as evening star oil or blackcurrant oil. It is rich in linoleic acid (Omega-6 fatty acid) and gamma-linolenic acid (Omega-3 fatty acid), which are beneficial for human health, especially in regulating the endocrine system, improving skin health, and reducing inflammation.

Manufactured:

Evening primrose oil is mainly derived from evening primrose seeds, extracted through cold pressing or subcritical low-temperature extraction. Natural evening primrose oil is light yellow and contains about 90% unsaturated fatty acids, with the highest content being around 70% linoleic acid (LA) and about 7-10% gamma-linolenic acid (GLA). Since both LA and GLA are highly unsaturated fatty acids (containing many double bonds), the oil has relatively high stability but is prone to oxidation when exposed to air. Therefore, most evening primrose oils on the market are supplemented with a small amount of vitamin E as an antioxidant to maintain quality and stability.

Function:

1. Evening primrose oil is beneficial for regulating blood lipids.

Dyslipidemia is a condition characterized by changes in one or more blood lipid components, including total cholesterol, low-density lipoprotein cholesterol, triglycerides, and high-density lipoprotein cholesterol, and is a significant risk factor for cardiovascular disease. It is estimated that the prevalence of dyslipidemia is 38.6% in individuals aged 40 and above and 20% in children and adolescents aged 8 to 17. A meta-analysis of six randomized controlled trials involving 201 participants found that supplementation with evening primrose oil did not significantly reduce total cholesterol, triglycerides, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol. However, subgroup analysis revealed that the effects of lowering triglycerides and increasing high-density lipoprotein cholesterol were observed in daily doses of ≤4g and in patients with hyperlipidemia.* Conclusion: Supplementing with evening primrose oil may positively affect lipid regulation, but more research is needed to further validate this due to limitations such as small sample sizes and heterogeneity among studies.

2. Evening primrose oil improves premenstrual syndrome

Premenstrual syndrome (PMS), commonly known as premenstrual tension, refers to various physiological and psychological discomforts that occur in the period before menstruation. It is estimated that about 80% to 90% of women of childbearing age experience these troubles. The causes of PMS are still debated, with one common explanation being a deficiency in the prostaglandin PGE1 and elevated levels of prolactin. Evening primrose oil, rich in gamma-linolenic acid (GLA), has been found to increase PGE1 and inhibit prolactin, thus believed to alleviate PMS. Literature indicates conflicting views on the effectiveness of evening primrose oil in improving PMS. Early studies tended to support its efficacy (though with design flaws and a lack of control groups), while recent research has shown no superiority over placebo or only slight improvement.* Conclusion: To date, no large-scale experiment has confirmed that evening primrose oil can help improve premenstrual syndrome.

3. Evening primrose oil improves menopausal hot flashes

Hot flashes are a rapid heat dissipation response in the human body, characterized by profuse sweating, peripheral vasodilation, and intense heat sensation. It is a common phenomenon in menopausal women, with an incidence rate between 30% and 80%. It usually lasts for one year, but in some cases, it can persist for up to 10 years, causing significant disruption to quality of life and sleep. A randomized, double-blind controlled study (6 weeks, 56 menopausal women) found that compared to a placebo, oral evening primrose oil not only reduced the intensity of hot flashes but also improved the related quality of life interference score (HFRDIS score), especially in social activities, relationships with others, and sexual activities.* Conclusion: Evening primrose oil may benefit hot flashes associated with menopause in women, but further empirical evidence is needed to confirm this.

4. Evening primrose oil improves cyclical breast pain

Cyclical mastalgia is related to the menstrual cycle. It is a pain caused by breast tissue, which is the most common breast symptom, occurring in 70% of women in their lifetime, especially more common in young women, mostly self-resolving, and should be distinguished from premenstrual syndrome. Breast pain is bilateral, diffuse, and poorly localized, usually described as a heaviness or pain radiating to the armpits and arms. It most commonly occurs in the luteal phase and is believed to result from increased hormone levels leading to increased water content in the breast stroma. A double-blind, randomized, placebo-controlled trial (lasting six months, involving 85 women with premenstrual cyclical breast discomfort) indicated that oral evening primrose oil (daily dose of 3000 mg) could reduce the severity of cyclical mastalgia.* Conclusion: For women with cyclical breast pain, oral evening primrose oil may provide some positive benefits, but more research is needed to confirm this due to the limited sample size.

5. Evening primrose oil improves skin texture

The skin is the human body's largest organ, serving as a barrier to prevent water loss, protect against harmful compounds or organisms from the environment, and provide protection from solar radiation. The skin is characterized by active lipid metabolism and has a unique lipid structure, serving as a source of a range of bioactive lipid mediators. It also plays a role in sensing pain, temperature, and touch, helping to regulate body temperature, and mediating inflammatory and immune responses. A randomized, double-blind, placebo-controlled study (12 weeks, 40 adults) indicated that oral evening primrose oil may help improve skin biophysical parameters, including transepidermal water loss, firmness, elasticity, fatigue resistance, and roughness.Conclusion: Oral evening primrose oil may have a positive effect on improving skin condition, but more large-scale trials are needed to confirm this due to the limited sample size.