{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,22]],"date-time":"2026-01-22T00:06:16Z","timestamp":1769040376552,"version":"3.49.0"},"reference-count":51,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2022,9,21]],"date-time":"2022-09-21T00:00:00Z","timestamp":1663718400000},"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>Vitamin C (VC) intakes, serum VC, fasting plasma glucose, and A1c levels of 25,206 adult men and 26,944 adult women with 6807 type 2 and 428 type 1 diabetes from the NHANES database between 1999 and 2018 were analyzed. Our hypothesis is that low VC intake and serum VC level may be a health risk for US adults with diabetes. Analyses revealed total VC intake below the estimated average requirement (EAR) increased from 38.1% to 46.5% between 1999\u20132018. VC intake and serum VC levels were inversely associated with markers of pre-diabetes and type 2 diabetes, namely, fasting plasma glucose and A1c levels. Risks of type 2 diabetes increased in adults with VC intake below the EAR and with no VC supplement (odds ratio 1.20, 95% CI 1.1\u20131.3 and 1.28, 95% CI 1.18\u20131.40, respectively). Median survivor years of diabetic adults with lower and deficient serum VC were shorter than that of diabetic adults with normal serum VC. Mortality risks of type 2 diabetes with low VC intake and\/or deficient serum VC levels were elevated compared to those with adequate VC intake and normal serum VC (HR 1.25, 95% CI 1.05\u20131.49 and 1.84, 95% CI 1.10\u20133.08, respectively). Observation of declining VC intake and deleterious consequences of low serum VC in US adults with diabetes suggests encouragement of VC intake, including VC supplementation of 500\u20131000 mg\/day, may be beneficial for pre-diabetic and diabetic US adults.<\/jats:p>","DOI":"10.3390\/nu14193902","type":"journal-article","created":{"date-parts":[[2022,9,22]],"date-time":"2022-09-22T05:33:14Z","timestamp":1663824794000},"page":"3902","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["Decreasing Vitamin C Intake, Low Serum Vitamin C Level and Risk for US Adults with Diabetes"],"prefix":"10.3390","volume":"14","author":[{"given":"Hongbing","family":"Sun","sequence":"first","affiliation":[{"name":"Environmental Health Laboratory, Department of Earth and Chemistry, Rider University, 2083 Lawrenceville Road, Lawrenceville, NJ 08648, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jonathan","family":"Karp","sequence":"additional","affiliation":[{"name":"Department of Biology, Behavioral Neuroscience and Health Sciences, Rider Univerisy, 2083 Lawrenceville Road, Lawrenceville, NJ 08648, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kevin M.","family":"Sun","sequence":"additional","affiliation":[{"name":"Department of Biology, Johns Hopkins University, 3400 N Charles St, Baltimore, MD 21218, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Connie M.","family":"Weaver","sequence":"additional","affiliation":[{"name":"School of Exercise & Nutritional Sciences. San Diego State University, 5500 Campanile Dr, San Diego, CA 92182, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,21]]},"reference":[{"key":"ref_1","unstructured":"US Department of Health and Human Services (USDHHS)1 (2022, May 06). National Diabetes Statistics Report (USNDSR), Available online: https:\/\/www.cdc.gov\/diabetes\/pdfs\/data\/statistics\/national-diabetes-statistics-report.pdf."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"107843","DOI":"10.1016\/j.diabres.2019.107843","article-title":"Global and regional diabetes prevalence estimates for 2019 and projections for 2030 and 2045: Results from the International Diabetes Federation Diabetes Atlas","volume":"157","author":"Saeedi","year":"2019","journal-title":"Diabetes Res. Clin. Pract."},{"key":"ref_3","unstructured":"US National Center for Health Statistics (USCDC) (2022, May 06). 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