Low-dose supplementation with lycopene or beta-carotene does not enhance cell-mediated immunity in healthy free-living elderly humans.

Objective: To assess the effects of supplementation with the carotenoids, beta-carotene or lycopene, at levels achievable within a diet rich in fruit and vegetables, on immune function in a group of free-living healthy elderly.

Design: A double-blind randomized placebo-controlled trial. T cell subsets and the expression of functionally associated cell surface molecules, quantified by flow cytometry, and lectin-stimulated lymphocyte proliferation, were compared before and following the treatment period.

Subjects: Fifty-eight subjects aged over 65 y were recruited; 52 were included in the final analysis.

Interventions: Participants received one placebo, one lycopene (13.3 mg) or one beta-carotene (8.2 mg) capsule daily for 12 weeks.

Results: No significant differences were observed in any of the parameters examined following either lycopene or beta-carotene supplementation.

Conclusions: In well-nourished, free-living, healthy elderly individuals, supplementation with relatively low levels of beta-carotene or lycopene is not associated with either a beneficial or detrimental effects on several aspects of cell-mediated immunity.