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Dietary nitrate supplementation for preventing and reducing the severity of winter infections, including COVID-19, in care homes (BEET-Winter): a randomised placebo-controlled feasibility trial

Research output: Contribution to journalArticlepeer-review

for BEET-Winter Investigators, Philip M Bath, Cameron J C Skinner, Charlotte S Bath, Lisa J Woodhouse, Anastasia Areti Kyriazopoulou Korovesi, Hongjiang Long, Diane Havard, Christopher M Coleman, Timothy J England, Valerie Leyland, Wei Shen Lim, Alan A Montgomery, Simon Royal, Amanda Avery, Andrew J Webb, Adam L Gordon

Original languageEnglish
Pages (from-to)1343-1355
Number of pages13
JournalEuropean Geriatric Medicine
Issue number6
Early online date16 Nov 2022
Accepted/In press31 Oct 2022
E-pub ahead of print16 Nov 2022
PublishedDec 2022

Bibliographical note

© 2022. The Author(s). Funding Information: We thank the participating care homes, residents and their families who participated in and supported this trial. Publisher Copyright: © 2022, The Author(s).

King's Authors


PURPOSE: Infections cause considerable care home morbidity and mortality. Nitric oxide (NO) has broad-spectrum anti-viral, bacterial and yeast activity in vitro. We assessed the feasibility of supplementing dietary nitrate (NO substrate) intake in care home residents.

METHODS: We performed a cluster-randomised placebo-controlled trial in UK residential and nursing care home residents and compared nitrate containing (400 mg) versus free (0 mg daily) beetroot juice given for 60 days. Outcomes comprised feasibility of recruitment, adherence, salivary and urinary nitrate, and ordinal infection/clinical events.

RESULTS: Of 30 targeted care homes in late 2020, 16 expressed interest and only 6 participated. 49 residents were recruited (median 8 [interquartile range 7-12] per home), mean (standard deviation) age 82 (8) years, with proxy consent 41 (84%), advance directive for hospital non-admission 8 (16%) and ≥ 1 doses of COVID-19 vaccine 37 (82%). Background dietary nitrate was < 30% of acceptable daily intake. 34 (76%) residents received > 50% of juice. Residents randomised to nitrate vs placebo had higher urinary nitrate levels, median 50 [18-175] v 18 [10-50] mg/L, difference 25 [0-90]. Data paucity precluded clinical between-group comparisons; the outcome distribution was as follows: no infection 32 (67%), uncomplicated infection 0, infection requiring healthcare support 11 (23%), all-cause hospitalisation 5 (10%), all-cause mortality 0. Urinary tract infections were most common.

CONCLUSIONS: Recruiting UK care homes during the COVID-19 pandemic was partially successful. Supplemented dietary nitrate was tolerated and elevated urinary nitrate. Together, infections, hospitalisations and deaths occurred in 33% of residents over 60 days. A larger trial is now required.

TRIAL REGISTRATION: ISRCTN51124684. Application date 7/12/2020; assignment date 13/1/2021.

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