Kinetics of Retinol and TBS Among Lactating Senegalese Women Living in an Urban Setting and the Relationship Between Their TBS and Those of Their Infants

Vitamin A deficiency (VAD) is still a serious public health problem in most developing countries. Several strategies are used to prevent and address the consequences of this deficiency and to reduce its prevalence, particularly in Africa. In Senegal, the prevalence of VAD, although low among women of reproductive age, is quite worrying among children under 5 years old. In 2009, the fortification of refined oil with vitamin A was made mandatory in addition to the strategies already in place. The study of the impact of these strategies on the vitamin A status of women and children, showed relatively stable prevalences between 2010 and 2018. However, this study used plasma retinol concentration as an indicator. It is known that evaluation of vitamin A status is relatively insensitive when based on changes in plasma retinol concentrations, which are homeostatically controlled and negatively affected by subclinical infections. Incremental studies in the Dakar region using the modified relative dose response (MRDR) test in children under 2 years of age have indicated adequate vitamin A stores and a low prevalence of vitamin A deficiency in these children. The various strategies to prevent and control vitamin A deficiency have reportedly improved and even increased vitamin A stores in women and children, particularly in the Dakar region. Indeed, the latter benefit from substantial intakes of preformed retinol through the fortification program, and the majority of children under 2 years of age are breastfed. The aim of this study is to use a more sensitive method than plasma retinol, the retinol isotope dilution (RID) test, to assess the actual status of subjects following these different strategies and to better orient the policies implemented in Senegal.