Use of a ‘Super-child’ approach to assess the Vitamin A equivalence of Moringa oleifera leaves, develop a compartmental model for Vitamin A kinetics, and estimate Vitamin A total body stores in young Mexican children

Authors: LOPEZ-TEROZ, VERONICA - Universidad De Sonora; FORD, JENNIFER - Jean Mayer Human Nutrition Research Center On Aging At Tufts University; GREEN, MICHAEL - Pennsylvania State University; TANG, GUANGWEN - Jean Mayer Human Nutrition Research Center On Aging At Tufts University; Grusak, Michael; QUIHUI-COTA, LUIS - Centro De Investigacion En Alimentaction Y Desarollo; MUZHINGI, TAWANDA - International Potato Centre; PAZ-CASSINI, MARIELA - Centro De Investigacion En Alimentaction Y Desarollo; ASTIAZARAN-GARCIA, HUMBERTO - Centro De Investigacion En Alimentaction Y Desarollo

Submitted to: Journal of Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/21/2017
Publication Date: 9/20/2017
Citation: Lopez-Teros, V., Ford, J., Green, M., Tang, G., Grusak, M.A., Quihui-Cota, L., Muzhingi, T., Paz-Cassini, M., Astiazaran-Garcia, H. 2017. Use of a ‘Super-child’ approach to assess the Vitamin A equivalence of Moringa oleifera leaves, develop a compartmental model for Vitamin A kinetics, and estimate Vitamin A total body stores in young Mexican children. Journal of Nutrition. 147:2356-2363. https://doi.org/10.3945/jn.117.256974.
DOI: https://doi.org/10.3945/jn.117.256974

Interpretive Summary: Vitamin A deficiency continues to be a major nutritional problem in populations throughout the developing world. Vitamin A can be obtained through the conversion of pro-vitamin A carotenoids, like beta-carotene, which are contained in many plant foods. Moringa is a tree that is grown in several developing countries and its leaves are harvested and consumed as a human food source. While its leaves are known to contain beta-carotene, little is known about the efficiency of its conversion to vitamin A, especially in children. In this study, we grew Moringa plants in a way that allowed us to incorporate a unique form of hydrogen into the beta-carotene molecules. Leaves were fed to young children and blood samples were collected over time. Samples were analyzed and a special data analysis approach was used to show how well the beta-carotene was converted to vitamin A. These results demonstrated that Moringa leaves can be an important source of vitamin A for young children.

Technical Abstract: Background: Worldwide, an estimated 250 million children <5 y old are vitamin A (VA) deficient. In Mexico, despite ongoing efforts to reduce VA deficiency, it remains an important public health problem; thus, food-based interventions that increase the availability and consumption of provitamin A–rich foods should be considered. Objective: The objectives were to assess the VA equivalence of 2H-labeled Moringa oleifera (MO) leaves and to estimate both total body stores (TBS) of VA and plasma retinol kinetics in young Mexican children. Methods: Beta-Carotene was intrinsically labeled by growing MO plants in a 2H2O nutrient solution. Fifteen well-nourished children (17–35 mo old) consumed pureed MO leaves (1 mg beta-carotene) and a reference dose of [13C10] retinyl acetate (1 mg) in oil. Blood (2 samples/child) was collected 10 times (2 or 3 children each time) over 35 d. The bioefficacy of MO leaves was calculated from areas under the composite ‘‘super-child’’ plasma isotope response curves, and MO VA equivalence was estimated through the use of these values; a compartmental model was developed to predict VA TBS and retinol kinetics through the use of composite plasma [13C10] retinol data. TBS were also estimated with isotope dilution. Results: The relative bioefficacy of beta-carotene retinol activity equivalents from MO was 28%; VA equivalence was 3.3:1 by weight (0.56 mmol retinol:1 mmol beta-carotene). Kinetics of plasma retinol indicate more rapid plasma appearance and turnover and more extensive recycling in these children than are observed in adults. Model-predicted mean TBS (823 mmol) was similar to values predicted using a retinol isotope dilution equation applied to data from 3 to 6 d after dosing (mean 6 SD: 832 6 176 mmol; n = 7). Conclusions: The super-child approach can be used to estimate population carotenoid bioefficacy and VA equivalence, VA status, and parameters of retinol metabolism from a composite data set. Our results provide initial estimates of retinol kinetics in well-nourished young children with adequate VA stores and demonstrate that MO leaves may be an important source of VA.