{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,16]],"date-time":"2026-07-16T10:49:37Z","timestamp":1784198977457,"version":"3.55.0"},"reference-count":47,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2021,5,22]],"date-time":"2021-05-22T00:00:00Z","timestamp":1621641600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Background: It has been hypothesized that flavonoid ingestion stimulates immunity, promotes health, and prevents human illness. The aim of this analysis was to evaluate the association of the levels of immunoglobulin A (IgA) with the prevention of influenza infections and with the polyphenols contained in Okinawan vegetables. Methods: IgA, immunoglobulin G (IgG), immunoglobulin M (IgM), and soluble interleukin-2 receptor (sIL-2R) levels were measured in 44 outpatients who regularly ingested vegetables grown on Okinawa Island (200\u2013300 g\/day for \u2265 300 days\/year) with no history of influenza infection and in 73 patients who ingested the vegetables irregularly or not at all with a history of influenza infection. Results: The patients who regularly ate Okinawan vegetables had higher IgA, IgG, and IgM levels than those who did not. On the other hand, patients who did not consume Okinawan vegetables and had influenza had lower IgA, IgG, and IgM levels. In addition, the IgA and IgG levels showed significant positive correlations with the sIL-2R levels in both groups. Conclusions: It may be beneficial to eat vegetables abundant in polyphenols every day. Secretory IgA antibodies are an important part of the immune defense against viral diseases. People who ingest Okinawan vegetables have high IgA levels and might be more likely to develop immunity against influenza RNA viruses.<\/jats:p>","DOI":"10.3390\/nu13061773","type":"journal-article","created":{"date-parts":[[2021,5,24]],"date-time":"2021-05-24T00:01:20Z","timestamp":1621814480000},"page":"1773","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Ingestion of Okinawa Island Vegetables Increases IgA Levels and Prevents the Spread of Influenza RNA Viruses"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7671-1808","authenticated-orcid":false,"given":"Kenji","family":"Gonda","sequence":"first","affiliation":[{"name":"Department of Medicine, Daido Central Hospital, 1-1-37, Asato, Nah City 902-0067, Okinawa, Japan"},{"name":"Department of Gastrointestinal Tract Surgery, Fukushima Medical University, 1, Hikarigaoka, Fukushima City 960-1295, Fukushima, Japan"},{"name":"Fukushima Medical University, 1, Hikarigaoka, Fukushima City, Fukushima 960-1295, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hideto","family":"Kanazawa","sequence":"additional","affiliation":[{"name":"Department of Medicine, Daido Central Hospital, 1-1-37, Asato, Nah City 902-0067, Okinawa, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Goki","family":"Maeda","sequence":"additional","affiliation":[{"name":"Department of Regional Agricultural System Section, Okinawa Prefectural Agricultural Research Center, 820, Makabe, Itoman City 901-0336, Okinawa, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chisa","family":"Matayoshi","sequence":"additional","affiliation":[{"name":"Department of Medicine, Daido Central Hospital, 1-1-37, Asato, Nah City 902-0067, Okinawa, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Naoto","family":"Hirose","sequence":"additional","affiliation":[{"name":"Department of Research and Development section, Okinawa Industrial Technology Center, 12-2, Suzaki, Uruma City 904-2234, Okinawa, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yukiteru","family":"Katsumoto","sequence":"additional","affiliation":[{"name":"Department of Faculty of Science, Fukuoka University, 8-19-1, Nanakuma, Jonan City 814-0180, Fukuoka, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Koji","family":"Kono","sequence":"additional","affiliation":[{"name":"Department of Gastrointestinal Tract Surgery, Fukushima Medical University, 1, Hikarigaoka, Fukushima City 960-1295, Fukushima, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Seiichi","family":"Takenoshita","sequence":"additional","affiliation":[{"name":"Fukushima Medical University, 1, Hikarigaoka, Fukushima City, Fukushima 960-1295, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,22]]},"reference":[{"key":"ref_1","unstructured":"Okinawa Prefectural Government (2021, May 20). 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