Raising the bar for biofortification: enhanced levels of bioavailable calcium in carrots.

Recent efforts to increase the levels of Ca in the edible portions of plants have used a modified calcium/proton antiporter [known as short cation exchanger 1 (sCAX1)] to increase Ca transport into vacuoles. New work has shown that consumption of Ca-fortified carrots results in enhanced Ca absorption. These studies highlight the potential of increasing plant nutrient content through expression of a high-capacity transporter and illustrate the importance of demonstrating that the fortified nutrient is bioavailable.