The future is orange

Dark orange is better than paler, more neutral tones - at least, when referring to carrot colour, according to researchers studying the levels of beta-carotene in fruit and vegetables.

A scientist from the US Agricultural Research Service (ARS) and his collaborators at the University of Wisconsin-Madison studied how much beta-carotene people absorb from typical orange carrots and those with a darker orange colour.

Beta-carotene is an orange pigment found in carrots and other fruits and vegetables. It belongs to a group of compounds called carotenoids and has antioxidant properties that may reduce the incidence of cardiovascular disease and certain types of cancer. It is also an important source of vitamin A, which is necessary for normal vision, bone growth and tooth development.

The ARS reports that beta-carotene levels in carrots commonly consumed by Americans has gone up considerably since the 1970's (levels in some varieties now reach 160 ppm), due to the seed industry's changes to breeding lines.

In the recent ARS-UW study, male and female volunteers ate high-carotene carrots and carrots with average levels of the nutrient, with a 10-day carrot-free period in between. The researchers evaluated the volunteers' blood to determine how much pigment they absorbed. As predicted, the volunteers took up more beta-carotene from the high-carotene carrots. Further data analysis will help the researchers determine if higher carotene levels translate into increased vitamin A levels.

Vitamin A deficiency is a significant problem worldwide, especially in developing countries. The researchers believe making high-carotene carrots more readily available will help increase beta-carotene consumption and improve the vitamin A status of individuals who are deficient.