Dark-Orange Carrots Deliver More Beta-Carotene

Trendsetting stylists from the '70s may have had it right all along, according to an Agricultural Research Service scientist and his collaborators at the University of Wisconsin-Madison: Dark orange is better than subtler, more neutral tones.

At least, it is if you're referring to carrot color.

For 25 years, research geneticist Philipp Simon has been breeding improved lines of carrots at ARS' Vegetable Crops Research Unit in Madison. Recently, he teamed with nutritionists Sherry Tanumihardjo and Micah Horvitz of UW's Department of Nutritional Sciences to find out more about the human implications of his work. Together, they studied how much beta-carotene people absorbed from typical orange carrots and those with a darker orange color.

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.

In the early 1970s, the beta-carotene level in most carrots consumed in the United States was about 90 parts per million. By the early 1990s, beta-carotene levels in some varieties had reached 160 ppm, due in large part to the seed industry's incorporation of material provided by Simon into their 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.

ARS is the U.S. Department of Agriculture's chief scientific research agency.