Writing in the Journal of Agricultural and Food Chemistry, researchers examined the chemical make-up of hempseed oil - finding that the seed oil could be a valuable source of bioactive compounds for the food and cosmetic industries.
Supplementation with GLA and SDA appears to alleviate the symptoms of atopic dermatitis and other skin diseases in some patients. GLA and SDA content in hemp seed vary considerably with variety and this needs to be considered when using hemp oil to treat such symptoms.
The omega-6 to omega-3 ratio (n6/n3) in hemp seed oil is normally between 2:1 and 3:1, which is considered to be optimal for human health. Hemp seed oil, pressed from non-drug varieties of the Cannabis seed, is an especially rich source of the two EFAs, linoleic acid (18:2 omega-6) and alpha-linolenic acid (18:3 omega-3), in addition to their respective biologic metabolites, gamma-linolenic acid (18:3 omega-6) and stearidonic acid (18:4 omega-3).
Hempseed also has high levels of vitamins A, C and E and Beta-carotene, and it is rich in minerals like phosphorus, potassium, magnesium, sulfur and calcium.
Hemp with low THC content (0.3%) has been legalized by the European Union, and the global economic market for low-THC hemp - used in medicines, papers and fabrics - is valued at $100-200 million annually.
Led by Maria Angeles Fernandez-Arche from the University of Seville, Spain, the team behind the study noted that for millennia, people around the world cultivated cannabis for textiles, medicine and food - however hemp products have since been stigmatized because of their 'high'-inducing cousins.
According to Fernandez-Arche, however, hemp -- derived from low-hallucinogenic varieties of cannabis -- is making a comeback, not just as a source of fibre for textiles, but also as a crop packed with oils that have potential health benefits.
The aliphatic alcohols contained in hempseed oil have been known to reduce platelet aggregation. One of these alcohols, phytol, is associated with antioxidant and anticancer benefits, and can also be found in healthy foods such as spinach, beans, raw vegetables and asparagus.
"Hempseed has been documented as a folk source of food throughout recorded history, raw, cooked, or roasted, and hempseed oil (HSO) has been used as a food/medicine in China for at least 3000 years," noted the research team - who added that the ever-increasing demand for vegetables oils, coupled with current awareness about the nutritional and functional roles of fats in human diets, "has made it essential to characterize additional vegetable oil through innovative uses of its components and/or byproducts. "
The Spanish team explained that the beneficial effects of HSO are thought to be due to its balance between linoleic and linolenic acid content, but noted that so very far little effort has been focused to investigate the unsaponifiable fraction of HSO - which account for between 1.5% and 2% of the oil, and is an important source of interesting minor compounds.
"As part of ongoing investigations on bioactive secondary plant metabolites in medicinal and food plants, our aim of the present study was to conduct a detailed analysis and phytochemical characterization to correlate with those of literature reports to accelerate efforts to establish a global database for this valuable oilseed crop," explained Fernandez-Arche and colleagues.
They found that the unsaponifiable oil fraction contains a variety of 'interesting' substances including sterols, aliphatic alcohols and linolenic acids.
"A yield (1.84-1.92%) of unsaponifiable matter was obtained, and the most interesting compounds were beta-sitosterol, campesterol, phytol, cycloartenol, and gamma-tocopherol."
Empirical and Clinical Studies On Hemp Seed Oil
The system of traditional Chinese medicine maintains the oldest recorded source of information on hemp seed, both as a traditional food and medicine. In recent times, porridge of oats and hemp seed was used as an important source of nutrition in the Czech Republic, and at least one published report has described the application of hemp seed porridge, from folk medicine, in the treatment of tuberculosis without antibiotics.
More recent evidence has described how dietary fatty acids can be used in the treatment of this particular disease.
During the last decade, hemp seed oil has become available in speciality food shops throughout Europe and North America. Anecdotal reports attribute improvements in skin quality, stronger finger nails and thicker hair to modest daily usage (ca. 15-30 ml/day) over time; e.g., improvements in skin quality: 2-4 weeks, nails: 2-4 months and hair: 6-8 months. In both allopathic and traditional forms of medicine, such improvements are considered as good indications of general health. A recent clinical study with topically applied hemp seed oil has already demonstrated its usefulness in healing mucosal skin wounds after eye, nose and throat surgery. This finding is in line with numerous other clinical studies that have demonstrated the utility of EFAs and other polyunsaturated fatty acids in healing and immune response.
Mae Chan holds degrees in both physiology and nutritional sciences. She is also blogger and and technology enthusiast with a passion for disseminating information about health.