**2.2 Carotenoids in foods**

More than 700 naturally occurring carotenoids have been identified, and new carotenoids are continuously identified [17]. The nutritionally important carotenoids in human foods include the carotenes; β-carotene, α-carotene, and lycopene and the


#### **Table 1.**

*Major dietary carotenoids and their health properties.*

xanthophylls; β-cryptoxanthin, lutein, and zeaxanthin. These nutritionally important carotenoids are of major interest because they are detectable in the human plasma and can further be classified into provitamin A and non-provitamin A carotenoids. Provitamin A carotenoids are β-carotene, α-carotene, and β-cryptoxanthin, whereas non-provitamin A carotenoids are lutein, zeaxanthin, and lycopene [19]. Provitamin-A carotenoids are a major source of vitamin A, when ingested by human beings, they are converted into vitamin A, which has several important functions including vision, immune response, bone mineralization, reproduction, cell differentiation, and growth [20].

β-Carotene is the most widely distributed carotenoid in the human diet. α-Carotene is usually detected in similar foodstuff as β-carotene but in lower quantities. **Table 1** summarizes the main carotenoids in foodstuff and their effects on human health.
