Evening Primrose Oil, which comes from the seeds of the evening primrose wildflower, contains large amounts of the essential fatty acid gamma-linoleic acid (GLA).

Under ideal circumstances it is made in the body from conversion of linolenic acid. However there are factors which can prevent the conversion of linolenic acid to GLA. These factors include deficiencies in the vitamins B3, B6 and C and biotin and of the minerals Magnesium and Zinc.

It is thought that GLAs such as evening primrose oil assist weight loss by activating brown fat. Brown fat cells are specialised fat cells, which comprise 10% of total body fat and readily burn fat stores for energy. These fat cells are capable of burning ¼ of calories consumed.

A study of 38 individuals taking EPO showed that among the 22 who were within 10% of their ideal weight, none lost any weight. Patients over the 10% limit exhibited an average lose of 9 pounds.

Another study that took place in the University Hospital of Wales stated that people who are most likely to lose weight on evening primose oil are those with low sodium-potassium-ATPase activity.

A study in 1979 demonstrated that GLA is indeed effective in promoting weight loss. In this study thirty-eight people tool Gamma-linolenic acid in the form of evening primrose oil for a period of eight weeks. Half of the group lost an average of 9 pounds while taking 4 capsules per day while four subjects who took 8 capsules per day lost an average of 23 pounds. Only 5 people showed no weight change.

Gamma Linolenic acid is found in significant amounts in the seed oil from the Evening Primrose Plant, borage oil and blackcurrant seed oil. Doses from 90 mg to as much as 400mg of GLA have proven to be effective in weight loss programs.