Consumption of gold kiwifruit reduces severity and duration of selected upper respiratory tract infection symptoms and increases plasma vitamin C concentration in healthy older adults.

In the elderly, immunosenescence and malnourishment can contribute to increased risk and severity of upper respiratory tract infections (URTI). Gold kiwifruit (Actinidia chinensis 'Hort16A') contains nutrients important for immune function and mitigation of symptoms of infection, including vitamins C and E, folate, polyphenols and carotenoids. The objective of the present study was to evaluate whether regular consumption of gold kiwifruit reduces symptoms of URTI in older people, and determine the effect it has on plasma antioxidants, and markers of oxidative stress, inflammation and immune function. A total of thirty-two community-dwelling people (≥65 years) participated in a randomised crossover study, consuming the equivalent of four kiwifruit or two bananas daily for 4 weeks, with treatments separated by a 4-week washout period. Participants completed the Wisconsin Upper Respiratory Symptom Survey-21 daily, and blood samples were collected at baseline and at the end of each treatment and washout period. Gold kiwifruit did not significantly reduce the overall incidence of URTI compared with banana, but significantly reduced the severity and duration of head congestion, and the duration of sore throat. Gold kiwifruit significantly increased plasma vitamin C, α-tocopherol and lutein/zeaxanthin concentrations, and erythrocyte folate concentrations, and significantly reduced plasma lipid peroxidation. No changes to innate immune function (natural killer cell activity, phagocytosis) or inflammation markers (high-sensitivity C-reactive protein, homocysteine) were detected. Consumption of gold kiwifruit enhanced the concentrations of several dietary plasma analytes, which may contribute to reduced duration and severity of selected URTI symptoms, offering a novel tool for reducing the burden of URTI in older individuals.

Assessment of a rapid method for assessing adequacy of calcium intake.

The purpose of this study was to assess the agreement between the 24 h diet recall and a short 17-item 24 h food intake recall in assessing calcium intake. The calcium intakes of 21 women over the age of 50 were assessed by both methods on four occasions. The mean calcium intakes were similar using both methods, being 1034+/-398 mg/day by 24 h diet recall and 822+/-412 mg/day (SD) by 17-item 24 h food intake recall. The 17-item 24 h food intake recall tended to underestimate calcium intake compared with the 24 h diet recall, with the limits of agreement being between -1197 and -727 below and 370 and 682 mg/day above 24 h diet recall values over the four assessments. The 17-item 24 h food intake recall identified 8% more women with inadequate calcium intakes than the 24 h diet recall method did. Although there is poor agreement in calcium intake between the 24 h diet recall method and the 17-item 24 h food intake recall, the latter provides a quick and simple means for assessing extremes of calcium intake and whether day to day calcium intake is adequate.