Borage oil, also known as starflower oil, is a safe food supplement. The borage (Borago officinalis) plant is grown commercially for use in pharmaceutical and food industries. The harvested seed is cleaned and dried and then processed to extract the oil of which a natural percentage is gamma-linolenic acid (GLA), an Omega-6 type of polyunsaturated fatty acid (PUFA).
In borage oil, GLA is found as part of a triglyceride molecule. Bioavailability (the amount of the GLA that will be useful in the body when eaten) depends on the total amount of GLA in the oil and the position it is located on the triglyceride. These two factors depend on where and under what conditions the plants are grown, which breed of plant the oil is sourced from, and how the oil is processed.
The annual herb originated in the Middle-East or N. Africa but is now naturalised across the Mediterranean region and grown commercially in the UK, New Zealand, Canada and more recently Australia, China and Chile. Borage has been known to English herbalists for centuries cultivated for both culinary and medicinal uses and since the 1980s borage has been grown commercially.
The harvested seed is cleaned and dried and then processed to extract the oil (about 26-38% by weight) of which 17-28% is gamma-linolenic acid (GLA), in addition to GLA the oil also contains the fatty acids palmitic acid (10-11%), stearic acid (3.5-4.5%), oleic acid (16-20%), linoleic acid (35-38%), eicosenoic acid (3.5-5.5%), erucic acid (1.5-3.5%), and nervonic acid (1.5%).