Hemp, something previously associated with woven bags and tie dye, is now emerging as a popular health food.
Although the use of hemp for food, fiber and medicines is not new, it has recently become revived. There was a period of time when hemp crops were banned, many countries have since legalised edible hemp. Australia, who are a bit behind the ball, have only just made this move.
Inevitability there will be an explosion of hemp food products in the coming months, and with it there are sure to be some fantastic health claims attached.
What’s so great about hemp? Is it as healthy as promised or will we be adding it to the superfood wankery list?
Industrial hemp or edible hemp is grown under conditions that reduce the level of THC – the psychoactive component in marijuana – to levels below 0.5%.
Two components can be used the seeds and the oil.
Hemp oil is high in polyunsaturated fatty acids, has a unique fatty acid composition and is a great source of plant based omega 3 fatty acids.
The oil is cold pressed from the seeds and usually has a dark colour – this is a result of chlorophyll being present in the seed. This is a potential downside to the oil, as it needs to be kept in dark coloured glass, out of direct sunlight and has a short shelf life. The chlorophyll content causes the oil to go rancid over time or when exposed to sunlight.
Hempseed oil contains around 80% polyunsaturated fatty acids (PUFAs) and high amounts of essential fatty acids – these fats cannot be produced by the body and must come from the diet. Hempseed oil is particularly rich in the omega 6 fatty acids linoleic acid (LA) and steradonic acid and the omega 3 fatty acids alpha-linoleic acid (ALA) and gamma linoleic acid. (1)
Most interestingly the omega 6 and omega 3 fatty acids are present in the ratio of roughly 2.5:1 – which is thought to be around the ideal ratio for good health.(1, 2)
Balanced dietary intakes of omega 6 and omega 3 PUFAs are thought to have protective effects on cardiovascular health and reduce inflammatory conditions. Most western diets are too high in omega 6 fatty acids, and too low in omega 3 fatty acids – this disrupts the balance and could be a contributing factor to metabolic disease.(2, 3)
Hence the rational for recommending 2-3 serves of oily fish per week (due to their omega 3 content) and swapping saturated fats for PUFAs. Hemp oil has the potential to be an additional quality source of PUFA’s and may be particularly good for vegetarians and vegans who do not eat fish.
Due to this fatty acid profile, there are claims that eating hemp oil maybe be able to improve skin appearance and even some skin conditions.
One study of 16 participants suffering from eczema took either olive oil or hempseed oil for 8 weeks, then swapped to the other oil for another 8 weeks. There was a 4-week break in between. After using the hempseed oil participants reported a statistically significant reduction in skin dryness, skin itchiness and a reduced need to use medication. This doesn’t equate to proof that hemp oil improves skin health as this was only one study and it was small in size, more research is needed to explore these benefits.(4)
Hemp Oil Health Benefits
• A unique fatty acid composition and a good source of polyunsaturated fatty acids, making it a ‘healthy oil’.
• Ideal ratio of omega 6 and omega 3.
• May be beneficial for cardiovascular health and inflammatory disease due to omega 3 content. (2)
• Potential benefits for skin health but requires more evidence.
Hemp seeds are a good source of high quality plant protein, comparable to the quality of protein found in egg whites and soy beans.
The seeds typically contain around 25% protein, this percentage is even higher in hempseed meal. The meal is the fibrous solid part left over after the hemp seed oil is extracted, it is often used to make hemp protein powder or hemp flour.
Hemp seeds are also a good source of:
• vitamin E
• soluble and insoluble fiber. (1)
The protein found in the full hemp seeds and in the hemp meal, is easily digested and both contain a good amount of essential and non-essential amino acids. They also contain a high percentage of the amino acid arginine and glutamic acid, but low levels of lysine.(1, 5)
Because of the arginine content hempseeds have been attributed to beneficial effects on blood pressure, cardiovascular disease and some complications associated with type 2 diabetes. However, it is best to keep in mind these effects of arginine are seen when using L-arginine supplements so the direct effects from eating hempseeds is unknown.
Again, credited to the fatty acid content, hempseeds are said to have protective cardiovascular effects and possibly help control blood pressure.
Although the current studies have shown some promising results, they all used animals (rats and rabbits) therefore the cardiovascular effects cannot yet be translated to beneficial effects in humans.(6, 7)
Hemp Seed Health Benefits
• High quality protein source.
• High arginine and glutamic acid content.
• Arginine may have beneficial effects on cardiovascular disease, blood pressure and type 2 diabetes – effects from eating hemp not yet known.
• High in polyunsaturated fatty acids, may protect against cardiovascular disease – more evidence needed.
• Good source of vitamins and minerals.
Both hempseeds and hemp oil can be healthful additions to the diet.
Hemp oil is a good source of polyunsaturated fatty acids and hemp seeds are a great source of quality plant protein.
There may be some beneficial effect on skin health and cardiovascular health, but these claims are likely overhyped. More research is needed to tell if hemp is beneficial for any specific health outcomes.
Overall, it’s definitely one to add to the list of good nutrient dense foods. So, eat hemp if you like it, just beware of sensational health claims as research on hemp is still in its infancy.
1. Callaway J. Hempseed as a nutritional resource: an overview. Euphytica. 2004;140(1):65-72.
2. Simopoulos AP. The importance of the omega-6/omega-3 fatty acid ratio in cardiovascular disease and other chronic diseases. Experimental biology and medicine. 2008;233(6):674-88.
3. Kuhnt K, Degen C, Jaudszus A, Jahreis G. Searching for health beneficial n‐3 and n‐6 fatty acids in plant seeds. European journal of lipid science and technology. 2012;114(2):153-60.
4. Callaway J, Schwab U, Harvima I, Halonen P, Mykkänen O, Hyvönen P, et al. Efficacy of dietary hempseed oil in patients with atopic dermatitis. Journal of Dermatological Treatment. 2005;16(2):87-94.
5. House JD, Neufeld J, Leson G. Evaluating the quality of protein from hemp seed (Cannabis sativa L.) products through the use of the protein digestibility-corrected amino acid score method. Journal of agricultural and food chemistry. 2010;58(22):11801-7.
6. Al-Khalifa A, Maddaford TG, Chahine MN, Austria J, Edel AL, Richard MN, et al. Effect of dietary hempseed intake on cardiac ischemia-reperfusion injury. American Journal of Physiology-Regulatory, Integrative and Comparative Physiology. 2007;292(3):R1198-R203.
7. Prociuk M, Edel A, Richard M, Gavel N, Ander B, Dupasquier C, et al. Cholesterol-induced stimulation of platelet aggregation is prevented by a hempseed-enriched diet This article is one of a selection of papers published in the special issue Bridging the Gap: Where Progress in Cardiovascular and Neurophysiologic Research Meet. Canadian journal of physiology and pharmacology. 2008;86(4):153-9.