Dietary Intake of Carotenoids: Nutritional Status Assessment and the Importance of Considering Free and Ester Forms in Foods
Carotenoids display biological activities relevant to human health, and thus it is of great interest to evaluate their nutritional status, which can be carried out using different and complementary approaches, such as dietary intake assessment. This chapter focuses on the dietary intake of the major carotenoids found in the human diet and on dietary methods for their assessment. In the evaluation of food consumption, special attention should be given to fruit and vegetable intake. In food conversion into carotenoid intake, it is essential to provide the correct food identification and food intake estimates, as well as the food composition tables used. In most fruits and some vegetables, the main xanthophylls present in the human diet (lutein, zeaxanthin, β-cryptoxanthin) are found in the free form and also esterified with fatty acids. Although there is very little information on those ester forms, dietary xanthophylls are ingested to a greater degree as ester forms, for which a higher bioavailability and a higher conversion to retinol in the case of β-cryptoxanthin have been described. Finally, the adequacy of carotenoid intake is discussed in relation to its contribution to vitamin A intake and regarding the effects of individual carotenoids.