The recent legalisation of hemp as a food product in Australia has generated a lot of interest. Partly because it is unusual to have to ‘legalise’ a food, and partly because hemp is a food that’s particularly nutritious - definitely in the ‘superfood’ category! As a plant, hemp is really quite special in that it has so many uses for humans. We have been including hemp oil in our certified organic skin care for some years because it is so beneficial to the skin. But there is so much more to hemp than that. We thought it was timely to look at why you might want to consider making hemp products more a part of your life - in your food, clothing and paper as well as your skin care. Most of us think of hemp as a controversial plant because it is the source of marijuana. However, it is also the source of cannabidiol, or CBD, which has potentially significant medical benefits. What’s more, hemp’s environmental credentials are impressive.
What is the relationship between hemp, cannabis and CBD oil?
Hemp, or Cannabis sativa, is one of our oldest cultivated crops. It has been grown to provide fibre to manufacture fabric, rope, canvas and paper, as a source of food, and for its medicinal properties.
Most of the negative press about hemp comes from the fact that some varieties contain high levels of the psychoactive drug tetrahydrocannabinol (THC), used to produce cannabis or marijuana. Most of the THC is concentrated in the flower and to a lesser extent the leaves. With increasing use of marijuana in the west, the cultivation of all hemp was made illegal in many countries during the 20th century. In recent years, this ban was reversed in most countries for low THC hemp.
Another compound that can be extracted from the plant is cannabidiol, or CBD, which can be extracted from the plant into ethanol, and then concentrated as an oil, known as CBD oil. CBD was recently shown to block the effects of THC in the brain. CBD has also been shown to have potential for treating a range of medical conditions, including epilepsy, inflammation in the nervous system and nausea. In addition it may help with pain and anxiety and possibly other medical conditions. CBD can now be legally prescribed in Australia, but is still difficult to get hold of. CBD is traditionally extracted from flowers and leaves.
Whole hemp seeds are the ‘superfood’ part of the hemp plant, and the hemp seed oil we use in our certified organic skin care is pressed from the seeds. The hemp seeds and hemp seed oil that are legal to use in Australia contain negligible amounts of THC and CBD.
Over time, different strains of Cannabis sativa have been selected so that they produce good fibre for fabric and paper, large amounts of seeds, high levels of THC or CBD, or combinations of these. Some divide them into 2 different species, Cannabis indica and Cannabis sativa. However, as the two can form hybrids, the proportions of THC and CBD within a strain is unpredictable. The recent lifting of the ban on consumption of hemp in Australia applied only to strains that produce low quantities of THC (less than 0.0005%), and CBD (less than 0.0075%) (1).
Nutritional benefits of hemp seeds
Hemp seeds are the nutritious part of the plant, with quite a remarkable health profile. They contain around 25% protein, which is on a par with soy beans and red meat. The protein in hemp is very high quality: it contains all the essential amino acids and is easily digestible (2). The seeds contain around 20-30% carbohydrate and are an excellent source of fibre, around 10-15%. They also offer a good source of vitamin E and useful minerals.
The oil content of hemp seeds is quite unusual. They contain 25-30% oil, of which around 80% is polyunsaturated (2). The essential fatty acid profile, that is, the ratio of omega-6 to omega-3 essential fatty acids, is around 3:1. This 3:1 ratio is considered optimal for health. In western diets, where the ratio lies closer to 15:1, the overconsumption of omega-6 and/or underconsumption of omega-3 fatty acids can promote inflammation, cardiovascular disease, cancer and other diseases, while consumption of foods with the optimal profile can help reduce this risk (3). The fairly rare omega-6 fatty acid gamma-linolenic acid (GLA), which unlike other omega-6 fatty acids, can help reduce inflammation, is also present in reasonable quantities (4).
In addition to essential fatty acids, the oil component contains b-sitosterol, which has been reported to reduce uptake of cholesterol, and has reported anti-inflammatory effects.
How to eat hemp
Hemp seeds can be eaten whole or as a powder and sprinkled on food, added to smoothies and salads, made into pesto, dips and pasta sauces, baked into muffins or made into veggie burgers. Hemp seed oil is best unheated to preserve the integrity of the fats, and added fresh to dips, salads and smoothies.
Benefits of hemp seed oil to the skin
Because hemp seed oil is so abundant in the omega-3 and omega-6 fatty acids, and also contains the fairly rare omega-6 fatty acid, GLA, we have included it as a key ingredient in many of our certified organic skin care products. These essential fatty acids are extremely important in maintaining and restoring the skin’s essential barrier (read more about this here). Hemp also contains the anti-inflammatory b-sitosterols, and vitamin E which has antioxidant effects.
Environmental benefits of hemp
Hemp crops are resistant to pests, and because the plants are able to grow close together, they are able to out-compete weeds, which means fewer herbicides. The plant produces abundant leaves which drop to the ground, adding organic matter to the soil. The roots penetrate the soil deeply, meaning their water requirements are comparatively low, and the crop may also help reduce soil salinity.
Hemp grows rapidly under optimal conditions and crops can be harvested within a few months. They are more efficient and faster-growing than trees as a source of fibre for paper (5). Paper made from hemp also results in fewer emissions of toxic chemicals like chlorine and dioxins than paper made from wood. Because the crop grows quickly, it has a high nitrogen requirement, and has been proposed as a crop to remove excess nitrogen fertiliser from fields, reducing fertiliser runoff into waterways (6).
As a source of fibre for clothing, hemp needs virtually no pesticides, whereas cotton crops account for around 25% of world pesticide use. Cotton crops also need more water than hemp. Hemp’s high biomass means it is able to sequester carbon from the atmosphere efficiently (7).
What’s not to like about hemp?
It is only in recent years, now that cultivation of hemp is once again legal, that we are really understanding the benefits and advantages of hemp in so many parts of our lives. It seems we have a lot of catching up to do!
The last word is a quote from ‘Conversations with God’ by Neale Donald Walsch:
‘…Why not grow hemp and use it to make paper? Do you have any idea how many trees it takes just to supply your world with daily newspapers? To say nothing of paper cups, carry-out cartons, and paper towels?
Hemp can be grown inexpensively, and harvested easily, and used not only for making paper, but the strongest rope, and the longest-lasting clothing, and even some of the most effective medicines your planet can provide. In fact, cannabis can be planted so inexpensively, and harvested so easily, and has so many wonderful uses, that there is a huge lobby working against it.
Too many would lose too much to allow the world to turn to this simple plant which can be grown almost anywhere.
This is just one example of how greed replaces common sense in the conduct of human affairs.’
Callaway, J.C. (2004) Hempseed as a nutritional resource: An overview. Euphytica 140: 65–72
Simopoulos A.P. (2002) The importance of the ratio of omega-6/omega-3 essential fatty acids. Biomed Pharmacother. 56:365-79.
Leizer, C. et al. (2000) The Composition of Hemp Seed Oil and Its Potential as an Important Source of Nutrition Journal of Nutraceuticals, Functional & Medical Foods 2:35-53