Beta-carotene levels and vitamin A metabolization
Vitamin A has an important role in immune response, vision, embryonic development, and cell differentiation. Because we cannot synthesize vitamin A we must obtain it from the diet as preformed vitamin A from animal sources or as provitamin A carotenoids that can be found in fruits and vegetables.
The most abundant provitamin A carotenoid in the human diet is beta-carotene. It is mainly found in yellow-orange and dark green fruits and vegetables such as squash, carrots, mango, papaya. Carotenoid content in food is generally not altered by different cooking methods except extreme heat.
Beta-carotenoids, and carotenoids in general act as antioxidant substances that protect the organism against reactive oxygen species or ROS and play an important role in the prevention of multiple conditions including cardiovascular disease and diabetes. There are studies that suggest that carotenes have a protective effect on non-alcoholic fatty liver disease and lung cancer.
High doses supplementation with beta-carotene (>30 mg/d) has been associated with a negative outcome and increased mortality in smokers. Beta-carotene dosing should be assessed by your doctor according to your individual needs and health status.
Vitamin A delivery from provitamin A depends on absorption and conversion efficiencies to one of the main active vitamins A metabolites as retinal, retinol, and retinoic acid. Interindividual differences have been observed in provitamin A carotenoids absorption and transformation to biologically active vitamin A metabolites. It is hypothesized that single-nucleotide polymorphisms (SNPs) in genes that encode for enzymes involved in beta-carotene absorption and conversion can explain part of this variability.
Gene or region studied