Reference values for retinol, tocopherol, and main carotenoids in serum of control and insulin-dependent diabetic Spanish subjects

Abstract

Abstract To establish reference ranges for use in clinical and epidemiological studies, we determined concentrations of retinol, α-tocopherol, β-carotene, α-carotene, β-cryptoxanthin, lutein, zeaxanthin, and lycopene in 450 Spanish control subjects and 123 Spanish patients with insulin-dependent diabetes mellitus (IDDM). Results were grouped according to sex, and samples were collected throughout the year. Concentrations of retinol were significantly lower and β-carotene and α-carotene were higher in women than in men, both in controls and IDDM subjects, whereas β-cryptoxanthin concentrations were higher only in control women. Conditional logistic regression analysis showed that retinol, β-carotene, and lycopene were the variables associated with diabetes. In comparison with other populations, our controls showed, in general, ordinary concentrations of retinol, comparatively low β-carotene and high β-cryptoxanthin concentrations, and a relatively high α-tocopherol/cholesterol ratio.