A COMPARISON OF ANTIOXIDANT STATUS AND FREE-RADICAL PEROXIDATION OF PLASMA-LIPOPROTEINS IN HEALTHY-YOUNG PERSONS FROM NAPLES AND BRISTOL

Ischaemic heart disease mortality is much lower in Southern Italy than in the U.K. and this is not entirely explained by differences in classical risk factors. Differences in antioxidant intake, affecting free radical peroxidation of plasma lipoproteins, may be relevant. Therefore, dietary intake, antioxidant status and plasma lipid peroxidation were compared in healthy young persons eating typical regional diets from Naples (22) and Bristol (26). The Naples group consumed more fresh tomatoes, more fat as monounsaturates (from olive oil) and had higher plasma levels of the lipid antioxidants vitamin E (mean (SD; 95% CI) 29.1 (4.5; 26.8 to 31.3) vs 25.1 (3.86; 23.4 to 26.8) μmol I-1, P=0.005) and beta-carotene (4.74 (1.2; 4.14 to 5.34) vs 2.85 (0.8; 2.5 to 3.2) μmol. I-1, P<0.001). Intakes of vitamin C, total uncooked fruit and vegetables, plasma vitamin A, serum selenium and copper levels were similar. All indices of plasma lipid peroxidation were significantly lower in the Naples group: conjugated dienes (median (interquartile range; non-parametric 95% CI)) 29 (21.5-39.9; 24 to 36.7) vs 41.5 (37-48.5; 38 to 44.5) μmol. I-1, P<0.001; diene conjugation index 1.38 (1.02-1.55; 1.06 to 1.49) × 10-2 vs 1.57 (1.43-1.74; 1.44 to 1.71) × 10-2, P=0.019; lipid peroxides (geometric mean (95% CI)) 1.24 (1.12 to 1.37) vs 4.58 (3.84 to 5.46) μmol. I-1, P<0.001.Low levels of free radical peroxidised lipoproteins in Southern Italians may contribute to their comparatively low incidence of ischaemic heart disease and may result from increased antioxidant protection by higher plasma vitamin E and beta-carotene levels, derived from high olive oil and tomato intakes. © 1994 The European Society of Cardiology.