Immunity and antioxidant capacity in humans is enhanced by consumption of a fruit and vegetable juice concentrate

Abstract

Fruits and vegetables possess phytochemicals that may strengthen immunity. In previous studies, an encapsulated fruit and vegetable juice concentrate (FVJC) protected cellular DNA from oxidative damage in elderly subjects, and increased plasma antioxidants. These studies were extended in a younger, possibly stressed population potentially at risk for illness. Fifty-nine healthy young (average age 26y) law students participated in a randomized, double-blind study in which they consumed either FVJC or placebo twice daily for 77 days. Blood was collected on days 1, 35, and 77 and processed to examine various immune and antioxidant parameters. Individuals consuming the FVJC capsules had an increase in the number of circulating γδ T-cells, and a reduction in lymphocyte DNA damage. Plasma levels of vitamin C, βcarotene, lycopene, and lutein increased significantly in the FVJC group. Although the number of self-reported illnesses between the groups was not different; there was a trend for the FVJC group to have fewer total symptom-days (p=0.085). Consumption of the FVJC capsules was effective in enhancing plasma antioxidant status, reducing cellular DNA damage, and facilitating beneficial immune activity as shown by increased γδ T-cells, which may result in shorter illnesses or reduced number of symptoms. Funded in part by NSA, Inc.