Evening Primrose Oil

What is it?

The evening primrose has a beautiful flower. The oil from this plant has been found to be of use in numerous conditions including eczema, rheumatoid arthritis, and the nerve impairments that can come with diabetes.

How does evening primrose oil work?

Our body requires certain fats and oils for proper functioning. Evening primrose oil contains a couple of very important essential fatty acids, including gamma-linolenic acid. These help our body produce natural anti-inflammatory substances called prostaglandins.

Borage and black currant oil are other plant sources of these essential fatty acids that are less expensive than evening primrose oil. According to a study published in Medical Science Research (1988;16:525), evening primrose oil supplementation produced up to ten times as much of these beneficial prostaglandins as did the other oils.

Much of the research on evening primrose oil has been done by Dr. David Horrobin in Nova Scotia, Canada. If you are a gardener, you know that varieties of plants differ. Dr Horrobin helped develop a particular variety of the evening primrose that has been found to produce more beneficial effects.

Who should take evening of primrose oil?

You are far better off eating a healthy diet and not needing evening primrose oil in the first place. Avoid margarine and other hydrogenated fats, alcohol, aspirin, processed food, and excessive meat and poultry. Eat freshly prepared grains, legumes, fruits, and vegetables. Organic produce is more likely to contain the zinc and other nutrients important in fatty acid metabolism. Vitamin C can stimulate the formation of the natural anti-inflammatory agents that our body makes from our food and from evening primrose oil.

How to take evening primrose oil

The dose of evening primrose oil varies from person to person. Be sure to take plenty of vitamin C as that enhances any benefit from the evening primrose oil. Vitamin E is important to prevent side effects from essential oils.

Many of these studies on evening primrose oil showed that many months of supplementation are required to produce a therapeutic effect.

Illness and evening primrose oil


There appears to be a link between low levels of gamma-linolenic acid and various allergic conditions. Some evidence that support this is

In Europe, the health authorities in England and several other European Countries have approved this brand of evening primrose oil as effective for eczema.

Rheumatoid arthritis

Evening primrose oil has been studied for rheumatoid arthritis. Sometimes patients have found their symptoms improved after two to three months. Some of these patients felt worse for a week or two and then felt better for a long time. In many other patients, especially if they have been receiving corticosteroids or other anti-inflammatory drugs, evening primrose oil has not been dramatically effective.

A study from the University of Pennsylvania was reported in the Annals of Internal Medicine (1993;119:867). Thirty capsules evening primrose oil were given twice a day over a period of six months to patients with severe rheumatoid arthritis. In comparison to placebo, the gamma-linolenic acid reduced the number of tender joints by a third; other measures of rheumatoid arthritis were improved as well. Relief occurred as early as six weeks in some of the patients. Of the seventeen patients getting the gamma linolenic acid, five of them were on steroids.

In a study in Arthritis and Rheumatism (1989; 32:1273), cells from a human joint capsule were artificially stimulated in the laboratory to become inflamed as they would in a person with rheumatoid arthritis. These cells were then treated with fatty acids derived either from evening primrose oil or from meat. Compared to the fatty acids from meat, the fatty acids from evening primrose oil reduced the inflammation by a factor of five. Indomethacin, a pharmaceutical antiinflammatory agent, interfered somewhat with this beneficial effect.

Ulcerative colitis

In a 1993 study at St. Thomas Hospital in London, a group of forty three patients were randomly chosen to take evening primrose oil, olive oil, or MaxEPA (a fish oil concentrate). After six months, it was found that of the three oils, only evening primrose oil made a difference. The patients taking the evening primrose oil had firmer stools, but no change in the appearance of the colon on sigmoidoscopy nor any lessening in the number of stools or amount of bleeding.

Diabetic neuropathy

In people with diabetes, one major problem is that the nerves can stop functioning. This can lead to damage to the feet as well as to other parts of the body and also significantly reduces the person's quality of life. Defects with essential fatty acid metabolism appear to contribute to this, and a number of studies of evening primrose have resulted. The most recent appeared in the Journal of Diabetes Care (1993; 16:8). Over 100 patients with mild nerve damage from diabetes were given six capsules of gamma-linolenic acid twice a day for a year, the others, placebo. Sixteen measures of nerve function were followed. Every measure improved in the group on gamma-linolenic acid in comparison with the group on placebo. For thirteen of the sixteen measures, the improvement was statistically significant. The treatment was more effective in those patients who were better at keeping their blood sugar relatively normal.

It is interesting that a study in Nutrition and Metabolism (1980; 24,supplement 1:105) showed that newly diagnosed diabetics had less cardiovascular disease when they were given more linoleic acid. Linoleic acid, of course is more common in a vegetarian type diet than on a meat diet. After five years, three of the men on the normal diet had died with a heart attack, compared to none with the essential fatty acid rich diet. Cardiac disease affected twenty two percent of the men in the control group compared with six percent of the men in the more vegetarian group. Evidence also indicated that the essential fatty acid rich diet protected the kidneys.

Prevention Of Hypertension

As it turns out, people aren't the only species to suffer from high blood pressure. Certain animals can be affected by high blood pressure. Gamma-linolenic acid can prevent these animals from developing high blood pressure.

Premenstrual syndrome

In women with PMS, the conversion of linoleic acid to gamma-linolenic acid is probably impaired. As a result, these women are unusually sensitive to the hormone prolactin, which is involved in the development of the breast and the production of milk. Most studies (but not all) have showed more relief of symptoms with evening primrose oil than with placebo. Evening primrose oil, a capsule three times a day, was usually given for three to four months.

In a study reported in the Lancet in 1985, forty five percent of women with painful breasts found a great reduction or an elimination of their pain after using six capsules of evening primrose oil a day for three to six months, compared to a twenty percent improvement in the placebo group.

Raynaud's syndrome

Raynauds syndrome is an illness in which people find that their fingers turn white and numb in the cold. Thrombosis and Hemostasis (1985;54:490) reported fewer attacks with evening primrose oil.


The British Journal of Clinical Practice (1987;41:907) reported on eleven patients with cancer of the liver. Nine to eighteen grams a day of gamma-linolenic acid resulted in marked clinical improvement in most patients who had already had maximum conventional therapy. There was an increase in survival time, and in most cases, an increase in weight.

If evening primrose oil doesn't appear to help your problem, you may not be absorbing it. Take 3 capsules pancreatic enzymes with each dose to enhance absorption.

As with any treatment, some people benefit more than others.

Will I benefit from evening primrose oil?

You will benefit from this if you are lacking in the essential fatty acids it contains. We can measure them, but it costs. I believe the most economical approach is to take evening primrose oil for a couple of months and see if it helps. It may take that long to see an effect.