How nettles improve immunity?
With the cold and flu season upon us, as well as the current covid-19 pandemic, taking care of our immune system has never seemed more pertinent. The abstract question of how to best take care of our immune system can be difficult to answer, though. To best answer this question, it is important to know how the immune system functions. A healthy immune system consists of three components: physical and biochemical barriers (e.g. skin, mucus, etc), immune cells, and antibodies. The first two elements of the immune system fight pathogens to prevent an infection before it occurs, while antibodies are designed to battle against a specific infection that is currently ongoing. To ensure healthy development and maintenance of all parts of the immune system, consumption of immune-specific nutrients like iron, vitamin A and C, and zinc is paramount. Nettles are rich in all of these vitamins and minerals, making them uniquely suited to support immune function.
Iron and zinc are components of enzymes that are critical for functional immune cells and iron specifically is involved in bodily processes that contribute to the destruction of bacteria. Vitamin C is also an important nutrient in immune function because it can increase serum antibody levels and has antimicrobial properties. Additionally, it contributes to the physical component of the immune system because it promotes collagen synthesis and cell integrity, and is an antioxidant that contributes to the regeneration of other antioxidants like vitamin E (which also protects the integrity of cell membranes). Vitamin A supports mucosal and immune cell function and supports anti-inflammatory responses in the body. In general, antioxidants like vitamin A and vitamin C, coupled with iron and zinc, make for a powerful nutritional cocktail against oxidative stress that can have negative effects on immune function. Deficiency in any of these nutrients can lead to an increased risk of infection and a reduced immune response.
Nettles combine all these immune-boosting nutrients into one convenient package. In fact, a serving of processed nettles (such as nettle powder) can meet 90-100% of vitamin A requirements and has 75 times the amount of iron as barley and wheat flour. Nettles are also a good source of zinc and vitamin C, the latter of which serves to increase the absorption of the nettle’s available iron. As an added benefit, nettles also contain a substantial amount of polyphenols, which have been shown to modulate the immune response in a positive way. Polyphenols also fortify the intestinal mucosal barrier, which helps protects the body against foreign invaders. The unique nutritional composition of nettles makes them a useful tool in the quest for a healthy immune system and a simple addition to any healthy diet!
Emily Bridges, MS, RD
 Maggini S, Pierre A, Calder PC. Immune Function and Micronutrient Requirements Change over the Life Course. Nutrients. 2018;10(10):1531. Published 2018 Oct 17. doi:10.3390/nu10101531
 Wintergerst ES, Maggini S, Hornig DH. Contribution of selected vitamins and trace elements to immune function. Ann Nutr Metab. 2007;51(4):301-323. doi:10.1159/000107673
 Rutto LK, Xu Y, Ramirez E, Brandt M. Mineral Properties and Dietary Value of Raw and Processed Stinging Nettle (Urtica dioica L.). Int J Food Sci. 2013;2013:857120. doi:10.1155/2013/857120
 Adhikari BM, Bajracharya A, Shrestha AK. Comparison of nutritional properties of Stinging nettle (Urtica dioica) flour with wheat and barley flours. Food Sci Nutr. 2015;4(1):119-124. Published 2015 Aug 7. doi:10.1002/fsn3.259
 Shonte TT, Duodu KG, de Kock HL. Effect of drying methods on chemical composition and antioxidant activity of underutilized stinging nettle leaves. Heliyon. 2020;6(5):e03938. Published 2020 May 23. doi:10.1016/j.heliyon.2020.e03938
 Jimoh F, Adedapo A, Aliero A, Afolayan A. Polyphenolic and biological activities of leaves extracts of Argemone subfusiformis (Papaveraceae) and Urtica urens (Urticaceae). Rev Biol Trop. 2010;58(4):1517-1531. doi:10.15517/rbt.v58i4.5428
 Ding S, Jiang H, Fang J. Regulation of Immune Function by Polyphenols. J Immunol Res. 2018;2018:1264074. Published 2018 Apr 12. doi:10.1155/2018/1264074