Long fibers are very valuable in textile industry. Their differential processing will lead us to obtain threads and tissues with a wide range of qualities, from very resistant ones for rigging, sailing, sacks, nets, burlap, espadrilles,… even thinner threads and tissues with great resistance and breathability properties, which make them ideal either for working clothes, conventional clothes, or high fashion.

In the action plan about circular economy of 2020, the European Commission identified textiles as a priority because of their significant perspectives for circularity. The action plan recognizes that “textiles are the fourth category for the use of primary raw material and water, after food, housing and transport; and the fifth one for greenhouse effect gas emissions”; besides the impact for the use of chemical products during their production and for the way they are wasted after their use (EEA, 2021; EC, s.f.).

Hemp represents a most respectful textile source with the environment, more than other fibers used nowadays.

It is more respectful than other natural fibers such as cotton, because of its lower hydric and phytosanitary requirements during cultivation.

In comparison with synthetic fibers, natural fibers as hemp, generate less impact because they do not come from a fossil source, contributing this way to not generating so much plastic waste and minimizing the emission both of greenhouse gasses and contaminant gasses.

Approximately between 200,000 and 500,000 tons of microplastic textile fibers come into the marine environment each year (Sherrington, 2016; Ellen MacArthur Foundation, 2017).

The problem of the plastic waste is not only their long half life until they finish their complete biodegradation process, but also their early transformation into microplastics, that due to their small size, are integrated into all the ecosystems and at all the levels of the trophic chain, triggering an important, both environmental and human, health problem.

Microplastics are peeled of the synthetic textiles throughout their life cycle: from the initial fiber and fabric manufacture, through the use and laundry, to their final disposal place ( landfill, incineration, or recycling processes). Approximately between 200,000 and 500,000 tons of microplastic textile fibers come into the marine environment each year (Sherrington, 2016; Fundación Ellen MacArthur, 2017).

But even with this clear benefit of the natural fibers over the synthetic ones, there is a need to consider that natural fibers use arable lands, decreasing the space for food crops. Thus, indiscriminate use of land to produce textiles is not a sustainable option either.

In this way, hemp represents a lower impact option for the environment than other natural fiber crops used to produce textiles, as it could be the case of cotton.

The reasons are related to:

1. the possibility of exploiting all the parts of the plant
2. hemp polyvalence, which could be intended to use each part in various industrial purposes
3. and the natural rusticity of hemp, which could be adapted to varied and difficult climate conditions as well as posses natural resistence to plagues and illnesses, limiting the use of phytosanitary products.

References

European Environment Agency, Published on 28 Jan 2021, Briefing no. 25/2020 Title: Plastic in textiles: towards a circular economy for synthetic textiles in Europe HTML – TH-AM-20-021-EN-Q – ISBN 978-92-9480-304-7 – ISSN 2467-3196 – doi: 10.2800/661804 PDF – TH-AM-20-021-EN-N – ISBN 978-92-9480-305-4 – ISSN 2467-3196 – doi: 10.2800/555165.

European Comission, s.f. A European Green Deal. https://ec.europa.eu/info/strategy/priorities-2019-2024/european-green-deal_en.

Sherrington C. Plastics in the Marine Environment. Eunomia Research & Consulting Ltd (2016), p. 13

The hemp stem contributes with applications for most of the industrial areas, with an added benefit that it is a sustainable raw material. Even in the technically demanding area of high technology, everyday there are innovative new applications for the micro or nano crystals of cellulose that could be extracted from hemp.

The method for processing the stem varies substantially according to the industrial destination that is pursued. The stem has various types of fibers that can be separated through a process known as decortication.

Decortication allows us to make the most of the stem fiber in the most efficient way, but it requires specialized machinery; therefore, the decision should be analyzed individually for each project.

The harvested and dry stem, without decortication, can be allocated in industries like the ones for pellet generation, package cardboards, or fiberboards for construction or furniture.

This stem,without decortication, is asustainable raw materialwith perspective for substituting other less sustainable ones, which use is actually established in several industrial sectors.. For example, pellet, cardboard, or fiberboard which come from hemp, help to confront deforestation and have a better carbon footprintthan the morecommon forest sources.

If, on the other hand, the decortication process is chosen for the post-processing of the hemp stem,, the decorticated fiber could be exploited in a higher number of industries that are more technically demanding with the raw material quality,as it could be the case of textile industryor the technological area.

The oil fraction of hempseeds is highlighted for its enormous proportion of non-saturated fatty acids (90%) and its high level of essential fatty acids, with a very optimum balance between them (figure 1) (Leonard et al. 2019; Farinon et al. 2020).

The only fatty acids that are considered essential for human beings are the 𝛼-Linoleic Acid (ALA) and the Linoleic Acid (LA), from the omega-3 and omega-6 family respectively. Being essential means that our organism cannot synthesize them, therefore, they have to be consumed obligatorily in the diet. The lack or deficit of these essential fatty acids in the diet can cause serious metabolic alterations.

According to the current dietary recommendations, essential fatty acids should be consumed in an adequate proportion, ideally in a relation 4:1 of omega-6: omega-3, until a maximum of 10:1 (Simopoulos, 2002; Gómez-Candela et al. 2011). 2011).

Somestudies show that even if there is evidence that keeping the proportion omega-3: omega-3 is important- especially under certain health circumstances-, what is really important is to keep a high intake of omega-3, even if the omega-6 is also high.

Hempseed oil has on average a 3:1 relation, which is only exceeded by the linseed oil (1:4). Olive oil has a relation 10:1 of omega 6: omega-3 (Figure 1).

These fatty oils and their intake in a correct proportion have been widely investigated for their antiinflammatory properties and their possible protective effects against hearth diseases, obesity, diabetes, inflammatory diseases, autoimmune diseases, and cancer (Sokoła-Wysoczańska et al., 2018; Simopoulos, 2002).

Furthermore, hempseed oil has 𝛾-linolenic acid (GLA), a long chain omega-6 fatty acid, which has high nutritional and metabolic importance. Kapoor and Huang (2006) describe the role of GLA in the regulation of inflammatory responses, acting as a biosynthetic precursor of the synthesis of anti-inflammatory eicosanoids.

Other important data is that the synthesis of this long chain fatty acid could be insufficient under some biological states as fetal development or breastfeeding. This is because the immature organism of the fetus and of the new born cannot synthesize it at a sufficient pace; therefore, they have to take it from their mother. Mothers can see their need to ingest essential fatty acids increased, and/or their correspondent derived long chain fatty acids, as GLA,, during those periods (Gómez Candela et al. 2011).

Finally, there is a scientific consensus regarding the idea that decreasing the ingest of saturated fats is beneficial for health (Kennedy et al. 2009). In comparison with other vegetable oils, hempseed oil has the highest proportion of polyunsaturated fatty acids (PUFA; Callaway, 2004; Leson, 2005). A reduction in the risk of heart diseases, cancer, rheumatoid arthritis, hypertension, inflammatory and autoimmune illnesses has been related to a higher ingest of PUFA (Abedi & Sahari, 2014).

Figure 1.

Hempseed fatty acid composition compared to other vegetable oils. Orderly, from left to right: almond, hazelnut, nut, hemp, linen, canola, soy, sunflower, and olive oils. Figure taken from Callaway, 2004 and Leson, 2005.

References

Abedi, E., & Sahari, M. A. (2014). Long-chain polyunsaturated fatty acid sources and evaluation of their nutritional and functional properties. Food science & nutrition, 2(5), 443–463. https://doi.org/10.1002/fsn3.121

Callaway JC. Hempseed as a nutritional resource: an overview. Euphytica: Netherlands Journal of Plant Breeding. 2004 ;140(1-2):65-72. DOI: 10.1007/s10681-004-4811-6.

Farinon B, Molinari R, Costantini L, Merendino N. The seed of industrial hemp (Cannabis sativa L.): Nutritional Quality and Potential Functionality for Human Health and Nutrition. Nutrients. 2020 Jun 29;12(7):1935. doi: 10.3390/nu12071935. PMID: 32610691; PMCID: PMC7400098.

Gómez-Candela, Carmen; Bermejo López, Laura M.; Loria-Kohen, Viviana. Importance of a balanced omega 6/omega 3 ratio for the maintenance of health. Nutritional recommendations. Nutrición Hospitalaria 26.2 (2011): 323-329

Kapoor R, Huang YS. Gamma linolenic acid: an antiinflammatory omega-6 fatty acid. Curr Pharm Biotechnol. 2006 Dec;7(6):531-4. doi: 10.2174/138920106779116874. PMID: 17168669.

Kennedy A, Martinez K, Chuang CC, LaPoint K, McIntosh M. Saturated fatty acid-mediated inflammation and insulin resistance in adipose tissue: mechanisms of action and implications. J Nutr. 2009 Jan;139(1):1-4. doi: 10.3945/jn.108.098269. Epub 2008 Dec 3. PMID: 19056664.

Leonard W, Zhang P, Ying D, Fang Z. Hempseed in food industry: Nutritional value, health benefits, and industrial applications. Compr Rev Food Sci Food Saf. 2020 Jan;19(1):282-308. doi: 10.1111/1541-4337.12517. Epub 2019 Dec 19. PMID: 33319519.

Leson, Gero. 2005. Hemp Seeds for Nutrition. Article from the European Industrial Hemp Association (EIHA) webpage. https://eiha.org/media/attach/83/hemp_seeds_for_nutrition.pdf

Simopoulos AP. Omega-3 fatty acids in inflammation and autoimmune diseases. J Am Coll Nutr. 2002 Dec;21(6):495-505. doi: 10.1080/07315724.2002.10719248. PMID: 12480795.

Sokoła-Wysoczańska E, Wysoczański T, Wagner J, Czyż K, Bodkowski R, Lochyński S, Patkowska-Sokoła B. Polyunsaturated Fatty Acids and Their Potential Therapeutic Role in Cardiovascular System Disorders-A Review. Nutrients. 2018 Oct 21;10(10):1561. doi: 10.3390/nu10101561. PMID: 30347877; PMCID: PMC6213446.

Hempseeds are highly appreciated in food industry, both human and animal, and also in cosmetic industry.

Once they are harvested, the highest quality seeds can be addressed for human consumption.

These seeds can be consumed entire, peeled, or they can be processed in order to get sub products of high food quality like seed oil or protean flour.

High quality oil can be acquired by the direct cold-pressed process of the seeds. This oil has a lipid composition that is very beneficial because of its high proportion of non-saturated fatty acids and their optimum balance of essential fatty acids.

Flour is made out of the defatted remains of the pressed seed, transforming it into food that is low in fat, but very rich in protein.

In the same way that there are varieties of medicinal hemp or fiber-producing hemp, there are also varieties that are super productors of seeds.

Seeds can be consumed entire, peeled, or in the shape of their derived products: oils or protean flour.

The nutritional value of hempseeds is getting great attention from the scientific community, even to the point of being considered functional food. This is that, apart from its nutritional value, it has components that are biologically active, which contribute with some additional and beneficial effect for health and reduce the risk of getting certain illnesses.