학술논문
SunGold Kiwifruit Consumption Restores Adequate to Optimal Vitamin C Status in People with a History of Severe Respiratory Infections.
Document Type
Academic Journal
Author
Vlasiuk E; Nutrition in Medicine Research Group, Department of Pathology and Biomedical Science, University of Otago, Christchurch 8011, New Zealand.; Zawari M; Nutrition in Medicine Research Group, Department of Pathology and Biomedical Science, University of Otago, Christchurch 8011, New Zealand.; Storer M; Respiratory Services, Christchurch Hospital, Christchurch 4710, New Zealand.; Maze MJ; Department of Medicine, University of Otago, Christchurch 8011, New Zealand.; Williman J; Department of Population Health, University of Otago, Christchurch 8011, New Zealand.; Chambers ST; The Infection Group, Department of Pathology and Biomedical Science, University of Otago, Christchurch 8011, New Zealand.; Carr AC; Nutrition in Medicine Research Group, Department of Pathology and Biomedical Science, University of Otago, Christchurch 8011, New Zealand.
Source
Publisher: MDPI AG Country of Publication: Switzerland NLM ID: 101668981 Publication Model: Electronic Cited Medium: Print ISSN: 2076-3921 (Print) Linking ISSN: 20763921 NLM ISO Abbreviation: Antioxidants (Basel) Subsets: PubMed not MEDLINE
Subject
Language
English
ISSN
2076-3921
Abstract
Severe respiratory infections are characterised by depleted vitamin C and elevated inflammation and oxidative stress. The aim of this study was to recruit people with a history of severe respiratory infections to undergo a six-week intervention with SunGold kiwifruit to determine if this could restore adequate vitamin C status. Secondary outcomes included changes in inflammatory and oxidative stress biomarkers, self-reported fatigue and subjective mood, and the incidence, duration and severity of respiratory symptoms. The total cohort comprised 20 adults (65% female, age range 31-84 years). The participants had a low median fruit and vegetable intake of 2.3 servings/day and a correspondingly low vitamin C intake of 46 mg/day. Circulating vitamin C status was a median of 45 µmol/L and was in the hypovitaminosis range in 25% of the cohort. Following intervention with two SunGold kiwifruit/day (equivalent to ~300 mg vitamin C), there was an increase in plasma vitamin C concentrations to >60 µmol/L ( p < 0.05). Approximately 20% of the participants were unable to reach adequate vitamin C status (≥50 µmol/L), possibly due to current smoking, which enhances vitamin C turnover, and a strong inverse correlation between body weight and vitamin C status (r = -0.734, p < 0.05). Following the intervention, there were indications towards decreases in the inflammatory biomarkers C-reactive protein and TNFα ( p > 0.05), but no changes in oxidative stress biomarkers (F 2 isoprostanes, protein carbonyls). There were decreases in fatigue and depression ( p < 0.05) and a lower number of individual respiratory symptoms reported during the kiwifruit intervention phase (8.5 vs. 10, p = 0.05). Overall, the consumption of two SunGold kiwifruit per day for six weeks was able to restore adequate to saturating vitamin C status in ~80% of the participants. Smokers and people with higher body weight may need larger doses and/or longer duration of supplementation. The contribution of vitamin C to reducing fatigue, depression, and number of respiratory symptoms warrants further investigation.