β‐Carotene decreases markers of lipid peroxidation in healthy volunteers

Abstract

We previously showed that daily intake of β‐carotene, a nontoxic antioxidant, reduces lipid peroxidation as assessed by serum lipid peroxide levels. An alternative method to detect lipid peroxidation is the measurement of pentane in breath. Pentane is a five‐carbon hydrocarbon that is released when an omega‐6 unsaturated fatty acid undergoes peroxidation. The aim of this study was to see whether graded doses of β‐carotene would affect breath pentane excretion in normal subjects placed on a carotenoid‐free liquid diet for two weeks. The subjects were then repleted with either 15 (n = 7) or 120 mg (n = 8) of β‐carotene daily for four weeks while continuing the same diet. Serum β‐carotene and breath pentane were measured before and after β‐carotene refeeding. Lipid peroxidation, as assessed by gas‐chromatographic measurement of breath pentane, was significantly (p < 0.05) reduced by daily supplements of 120 mg β‐carotene (from 3.7 ± 0.9 to 2.2 + 1.4 nmol/l). However, the decline in pentane exhalation observed with the 15‐mg β‐carotene dose did not achieve statistical significance (p = 0.13).