Wearing a mask, washing our hands, and social distancing are commonly recommended to slow the spread of SARS-CoV-2 infection. But, what about diet? In this video, I discuss the hypothesis that hesperidin, a metabolite found in lemons, oranges, and peppermint leaves, may contribute to the prevention and treatment of COVID-19.
Paper link: https://www.sciencedirect.com/science/article/pii/S030698772031358X
CD8+ T cells are a subset of lymphocytes that play a major role in antiviral defense (Kulinski et al. 2013). However, recently published evidence shows reduced levels of circulating CD8+ T cells in people infected with SARS-CoV-2 (Zheng et al. 2020, Wang et al. 2020; HC= healthy controls, NCP = patients with COVID-19 related pneumonia):
Immune enhancing treatments, including thymalfasin and immunoglobulin are being provided to SARS-COV-2 infected subjects with some success. For example, 37/55 (67%) subjects saw improvements for circulating CD8+ levels in Wang et al. 2020, but additionally, 18/55 subjects did not experience increased CD8+ counts:
Accordingly, levels of CD8+ T cells were identified as an independent predictor for COVID-19 severity and treatment efficacy (Wang et al. 2020). When considering that CD8+ cells were not increased in all subjects in Wang et al., are there are other strategies that may be helpful? Interestingly, increased levels of CD8+ cells are found in the lungs of mice infected with the influenza A virus in response to a high soluble-fiber diet, when compared with control-fed mice (Trompette et al. 2018):
As a result, lung viral load is more than 10-times reduced 8-days after infection in high soluble fiber-fed mice:
Moreover, average survival in mice infected with influenza A is significantly better when fed the high soluble-fiber diet, when compared with control fed-mice:
Is it possible that a high soluble fiber diet can increase CD8+ cells in people infected with SARS-CoV-2, thereby enhancing their recovery and survival? No studies have tested this hypothesis (yet). While conventional medical treatment is obviously helpful, based on the findings of Trompette et al. (2018), further optimization of immune defense against viral infections may occur when including soluble fiber-rich foods.
References
Kulinski JM, Tarakanova VL, Verbsky J. Regulation of antiviral CD8 T-cell responses. Crit Rev Immunol. 2013;33(6):477-88. Review.
Trompette A, Gollwitzer ES, Pattaroni C, Lopez-Mejia IC, Riva E, Pernot J, Ubags N, Fajas L, Nicod LP, Marsland BJ. Dietary Fiber Confers Protection against Flu by Shaping Ly6c– Patrolling Monocyte Hematopoiesis and CD8+ T Cell Metabolism. Immunity. 2018 May 15;48(5):992-1005.e8. doi: 10.1016/j.immuni.2018.04.022.
Wang F, Nie J, Wang H, Zhao Q, Xiong Y, Deng L, Song S, Ma Z, Mo P, Zhang Y. Characteristics of peripheral lymphocyte subset alteration in COVID-19 pneumonia. J Infect Dis. 2020 Mar 30. pii: jiaa150. doi: 10.1093/infdis/jiaa150.
Zheng M, Gao Y, Wang G, Song G, Liu S, Sun D, Xu Y, Tian Z. Functional exhaustion of antiviral lymphocytes in COVID-19 patients. Cell Mol Immunol. 2020 Mar 19. doi: 10.1038/s41423-020-0402-2.
Coronavirus isn’t the only virus that negatively affects human health.
For more info,
https://www.amazon.com/dp/B01G48A88A
Paper #1: Here I propose that the poor muscle composition (muscle that has fat in it) found in older adults may be related to an increased systemic microbial burden:
https://www.ncbi.nlm.nih.gov/pubmed/29030163
Paper #2: In this review, we discuss the emerging gut-muscle axis:
https://www.ncbi.nlm.nih.gov/pubmed/29058056
If you’re interested, please have a look at my book:
I recently heard centenarian Bernando Lapallo say that he boils his drinking water (http://www.abc15.com/news/local-news/water-cooler/valley-man-celebrates-114th-birthday-shares-his-longevity-secrets). Whether this is a contributor to or is merely associated with his longevity is debatable. What will boiling your water do, prior to drinking it, and is it worth the effort?
The ability of our immune system to combat infectious agents decreases with age (Ginaldi et al. 2001). Can we counteract this? Reducing intake of infectious agents would reduce the burden that our immune systems would have to deal with. Is it possible to reduce intake of infectious agents, including bacteria, viruses, and protozoa?
Boiling water can inactivate a variety of bacteria, viruses, and protozoa (WHO, 2015) that are increased in older adults. For example, as shown below, a water temperature greater than 60C (water boils at 100C) for 5 minutes will inactivate Escherichia Coli (E. coli). Why are E. coli important? E. Coli are elevated in older adults (70-90y), when compared with young (20-50y; Enck et al. 2009), and are associated with insulin resistance (Vrieze et al. 2012) and frailty (Claesson et al. 2012). Below we see that boiling water for 5 minutes would thermally inactivate E. Coli, potentially resulting in decreased work for our immune system.
Every morning I boil ~40 oz of water for my green tea. Later in the day in drink 10-20 oz of water, but not boiled. So, ~2/3 of my water intake is boiled, potentially reducing the infectious burden that my immune system has to battle. Whether boiling water reduces this burden by 1%, 10%, or more is unknown. However, based on the ability of water boiling to inactivate pathogens that are increased during aging, it may be a low risk (only the time used!), high reward strategy for improving health during aging. I’m actively considering boiling my 10-20 oz. of water at night, too.
7/2017 Update: In addition to boiling my water for green tea, I also use a high-powered water filter, the Big Berkey. I’m not paid to say that, but that’s what I do!
If you’re interested, please have a look at my book!
Reference:
Claesson MJ, Jeffery IB, Conde S, Power SE, O’Connor EM, Cusack S, Harris HM, Coakley M, Lakshminarayanan B, O’Sullivan O, Fitzgerald GF, Deane J, O’Connor M, Harnedy N, O’Connor K, O’Mahony D, van Sinderen D, Wallace M, Brennan L, Stanton C, Marchesi JR, Fitzgerald AP, Shanahan F, Hill C, Ross RP, O’Toole PW. Gut microbiota composition correlates with diet and health in the elderly. Nature, 2012. 488(7410): p. 178‐84.
Ginaldi L, Loreto MF, Corsi MP, Modesti M, De Martinis M. Immunosenescence and infectious diseases. Microbes Infect. 2001 Aug;3(10):851-7.
Enck P, Zimmermann K, Rusch K, Schwiertz A, Klosterhalfen S, Frick JS. The effects of ageing on the colonic bacterial microflora in adults. Z Gastroenterol, 2009. 47(7): p. 653‐8.
Vrieze A, Van Nood E, Holleman F, Salojärvi J, Kootte RS, Bartelsman JF, Dallinga-Thie GM, Ackermans MT, Serlie MJ, Oozeer R, Derrien M, Druesne A, Van Hylckama Vlieg JE, Bloks VW, Groen AK, Heilig HG, Zoetendal EG, Stroes ES, de Vos WM, Hoekstra JB, Nieuwdorp M. Transfer of intestinal microbiota from lean donors increases insulin sensitivity in individuals with metabolic syndrome. Gastroenterology, 2012. 143(4): p. 913‐6 e7.
World Health Organization. Boil Water. January 2015. http://www.who.int/water_sanitation_health/dwq/Boiling_water_01_15.pdf
Michael Lustgarten 