Biofortified and bioavailable: The gold standard for plant-based diets
Jeeyon Jeong and Mary Lou Guerinot*

Department of Biological Sciences, Dartmouth College, Hanover, NH 03755


Much of the world's population relies on a few staple foods (rice, maize, 
wheat, and cassava) that are poor sources of essential nutrients. 
Biofortification, the process of enriching the nutrient content of crops as 
they grow, provides a sustainable solution to malnutrition worldwide, 
because other methods, such as diversifying people's diets or providing 
dietary supplements, have proved impractical, especially in developing 
countries (1). One of the first biofortified crops was golden rice, which 
was engineered to produce beta-carotene or provitamin A in the edible 
portion of the grain (2). Since then, there have been similar successes with 
other crops, giving us a variety of carotenoid-enriched foods (1) as well as 
crops enriched with other micronutrients such as vitamin E (3) and folate 
(4). However, in each of these cases, assumptions about whether the 
nutrients are bioavailable-i.e., whether the nutrients can be readily 
absorbed by humans-remain untested. In a recent issue of PNAS, Morris et al. 
(5), using feeding studies with both mice and humans, report that carrots 
genetically engineered to accumulate twice as much calcium as control 
carrots are indeed a good source of this essential nutrient, resulting in a 
50% increase in calcium absorption.

http://www.pnas.org/cgi/content/extract/105/6/1777?etoc