[Serum status of carotenoids in control subjects and its relation to the diet]

Carotenoids are a group of fat soluble pigments which are present in the human being, both in blood, as in tissues, and which are obtained through the diet, mainly from fruits and vegetables. The interest of these compounds is due not only to the provitamin A activity of some of them, but also due to a whole series of biological activities such as: antioxidant or prooxidant, photo-protective, modulator of the immune response, anti-carcinogen, etc. The best analytical method available for the analysis of carotenoids is high performance liquid chromatography (HPLC), which is used in our study both for serum as for foods, and it is controlled throughout periodic quality controls. In this article we present the preliminary results of the levels of the major serum carotenoids (b-carotene, a-carotene, b-cryptoxanthin, lutein, zeaxanthin, and lycopene) in control subjects from five European countries, as well as indicating the major dietary contributors to the carotenoids intake in the Spanish population. The percentage of each carotenoid to the total of the carotenoids analyzed, varies according to the origin of the studied population. Ireland and the UK show a very similar carotenoids profile. France presents the highest levels of lutein and b-carotene, which are present simultaneously in green vegetables. Spain shows the lowest levels of b-carotene, along with the highest levels of b-cryptoxanthin, which in our country is supplied mainly by oranges and tangerines. The most abundant carotenoid in all countries was lycopene. The average daily intake of these carotenoids (from fresh fruits and vegetables) in our population, is 3.5 mg/day. Through the relationships between the dietary carotenoid contents and serum the identification of "biomarkers" have been proposed, which might be correlated with several pathological situations, and thus contribute to the prevention of certain diseases.