Nutritional, inflammatory, and ecological correlates of maternal retinol allocation to breast milk in agro‐pastoral Ariaal communities of northern Kenya

Abstract

Objectives Vitamin A (VA) is an essential micronutrient required for a range of biological functions throughout life. VA deficiency (VAD) claims an estimated 1 million preschool children’s lives annually. Human milk is enriched with VA (retinol) from the maternal blood, which originates from the hepatic reserve and dietary intake. Secreting retinol into milk will benefit the nursing infant through breast milk, but retaining retinol is also important for the maternal health. Previous studies found that the public health intervention of high-dose VA supplementation to lactating mothers did not significantly lower child mortality. WHO recently acknowledged that our understanding about the principle of VA allocation within the maternal system and the secretion into milk is too incomplete to devise an effective intervention. Methods We present a secondary analysis of data collected among lactating mothers in VAD endemic northern Kenya (n=171), examining nutritional, inflammatory, and ecological factors that might associate with maternal retinol allocation. Regression models were applied using the outcome milk-retinol allocation index: italicmilk0.16667emitalicretinolitalicmilk0.16667emitalicretinol+italicserum0.16667emitalicretinol. Results Ten percent of the sample was identified as VAD. The average milk retinol concentration was 0.1 μmo/L, grossly below what is considered minimally necessary for an infant (1 μmol/L). VAD mothers and mothers with inflammation did not seem to compromise their milk retinol even though their serum retinol was lower than non-VAD and non-inflammation mothers. Breastmilk fat concentration positively correlated with milk retinol but not with serum retinol. Conclusions This exploratory study contributes toward an understanding of maternal retinol allocation.

Variation in breast milk macronutrient contents by maternal anemia and hemoglobin concentration in northern Kenya

“…In the original study, data were collected from consenting mothers under approval of the community chiefs and the institutional review boards of the University of Washington and Kenya Medical Research Institute. Data collection took place during a prolonged drought and food shortage; many mothers were coping with the food shortage by reducing food variety, meal size or the number of meals for their consumption (Apland & Fujita, , , ; Apland, Fujita, & Chang, ; Fujita, ; Fujita, Apland, & Chang, ), and prioritizing their children in allocating limited amount of foods within households (Fujita, ). Our subsequent research found that low BMI (Fujita, ; Fujita, Brindle, Lo, Castro, & Cameroamortegui, ), vitamin A deficiency (Fujita, ; Fujita et al, ; Fujita, Lo, & Brindle, ), and iron deficiency (Fujita, Paredes Ruvalcaba, Wander, Corbitt, & Brindle, ; Fujita, Paredes Ruvalcaba, Wander, Corbitt, & Brindle, ; Fujita & Wander, ) were prevalent among these mothers.…”

“…Milk and blood sample collection methods have been described in depth elsewhere (Fujita, ; Fujita et al, , Fujita & Wander, ). In brief, breast milk collection took place following an overnight fast.…”

“…It took place in the Biomarker Laboratory for Anthropological research, supervised by MF, the principal investigator of the research. Preliminary findings have been presented at MSU University Undergraduate Research and Arts Forum and at a conference (Corbitt, Paredes Ruvalcaba, & Fujita, ; Fujita, Brindle, & Lo, ). Sample preparation and specimen analysis was funded by NSF (BCS #1638167) and the Wenner‐Gren Foundation (#9278) to MF.…”

Buffered or impaired: Maternal anemia, inflammation and breast milk macronutrients in northern Kenya

“…The same for anemia include BMI, age, parity, breastfeeding status, and inflammation/infectious disease (Alene & Mohamed Dohe, ; Antelman et al, ;Bodnar, Scanlon, Freedman, Siega‐Riz, & Cogswell, ; Semba et al, ). These variables except milk volume were available from our previous research (Fujita, ; Fujita et al, , , ; Fujita, Brindle, Lo, Castro, & Cameroamortegui, ; Fujita & Wander, ; Stone & Fujita, ) and utilized as covariates to adjust for their effects on milk characteristics.…”

“…The research on the associations between maternal inflammation/infection and milk components is inconsistent. Some studies suggest that maternal inflammation/infection may alter milk fatty acids or immune components (Gardner et al, ; Groer, Davis, & Steele, ; Mizuno et al, ), whereas others found no associations of subclinical inflammation with milk micronutrients (Fujita, Lo, & Brindle, ; Zavaleta et al, ).…”