Acta Scientific Nutritional Health (ASNH)(ISSN: 2582-1423)

Review Article Volume 6 Issue 4

Rice Consumption Enhancing Innate Immunity with a Reduced Risk of COVID-19 Infection and Mortality

Shaw Watanabe1,2* and Kazumoto Iinuma3

1Medical Rice Association; Tokyo, Japan
2Tokyo University of Agriculture; Tokyo, Japan
3Ricetech Corporation; Tokyo, Japan

*Corresponding Author:Shaw Watanabe, Medical Rice Association; Tokyo, Japan and Tokyo University of Agriculture; Tokyo, Japan.

Received: March 08, 2022; Published: March 21, 2022


Incidence and mortality of COVID-19 varied significantly by country. No clear hypothesis has been proposed to explain such an enormous difference. We found that annual rice consumption by country inversely correlated well to the cumulative number of COVID-19/million by compiling data from 17 major countries of G20. The negative correlation coefficient was 0.74, while wheat consumption showed a positive correlation. It suggested that the nature of staple foods supported primary resistance to SARS-CoV-2 infection. Early resistance to developing COVID-19 pneumonia would be cellular immunity and curable inflammation. Parallel increase of antibodies helped to eradicate pathogenic viruses. Pathologically, two plausible factors were sIgA, which mechanically blocked the virus from binding to the ACE2 receptor. Another factor was suppressing cytokine storm by regulatory T cells expanded by butyrate from intestinal microbiota.

The gut environment based upon the rice eating habit seemed essential to support a stable immune system byT17/Treg balance. Long rice-eating practices contributed to producing a secretary piece of IgA and growing particular microbiota composition, which had produced butyrate and other short-chain fatty acids, influencing various physiological functions. Rice eating would be the "X factor" by building solid innate immunity. However, different cultural habits, such as bowing etiquette, wearing face masks, and handwashing with sanitizing equipment, also suppress SARC-Co-2 infection. The suppressive action of the X-factor continued regardless of the different variants of SARS-Co-2. infection. The recent pandemic of Omicron seems to attenuate to habituate in human society as suggested from the historical aspect.

Keywords:COVID-19; Innate Immunity; Rice Eating; sIgA; Microbiota


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Citation: Shaw Watanabe and Kazumoto Iinuma. “Rice Consumption Enhancing Innate Immunity with a Reduced Risk of COVID-19 Infection and Mortality". Acta Scientific Nutritional Health 6.4 (2022): 80-90.


Copyright: © 2022 Shaw Watanabe and Kazumoto Iinuma. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


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