Increase Font Size Decrease Font Size View as PDF Print

Birth-24 Work Group 2 – Infancy: Period of Complementary Feeding (6-12 Months)

Each of the B-24 work group developed a set of topics and specific questions that might be the focus of future NEL systematic reviews, identified priority data needs (to be derived either from existing data sets, e.g., NHANES, or met with new data/surveillance) and described research priorities.

B-24 Work Group 2 discussed nutrition, metabolism and growth during months 6 through 12, particularly with regard to protein needs and long-term health.  Below is the list of topics and systematic review questions identified by Work Group 2. The full topic brief for Work Group 2 includes the data needs and research priorities for the topics as well as a reference list for each topic.
  • The impact of differences in protein intake in infants in the first 12 months of life
    • What is the association between relatively high intake of protein in infant formula vs. lower protein intake of human milk on 1) growth and physical development, 2) cognitive, behavioral, or neuromotor development, 3) overweight/obesity, 4) renal function, and 5) serum Insulin-like Growth Factor (IGF)-1 and insulin levels?
    • What is the association between protein intake on 1) growth and physical development, 2) cognitive, behavioral, or neuromotor development, 3) overweight/obesity, 4) renal function and solute load and 5) serum IGF-1 and insulin levels?
  • The role of beverages (including fruit juices and sugar-sweetened beverages) in complementary feeding between 6 and 12 months
    • What is the relationship between beverage consumption (including fruit juices and sugar-sweetened beverages) between 6 and 12 months of age and 1) growth and physical development, 2) oral health, 3) overweight/obesity, and 4) impact on achieving recommended dietary intake and/or diet quality?
  • Can fluid cow's milk be introduced before 12 months of age?
    • What is the relationship between consumption of fluid cow’s milk between 6 and 12 months of age and risk of iron deficiency or anemia?
    • What is the relationship between consumption of fluid cow’s milk between 6 and 12 months of age and growth and physical development?
  • Micronutrients of concern: iron, zinc, vitamin D, long-chain polyunsaturated fatty acids (LCPUFA), fluoride, and B12
    • What is relationship between iron intake and/or status and infant and toddler 1) cognitive, behavioral, or neuromotor development, 2) anemia, 3) growth and physical development, and 4) immune function?
    • What is relationship between zinc intake and/or status and infant and toddler 1) growth and physical development and 2) cognitive, behavioral, or neuromotor development, and 3) immune function?
    • What is relationship between vitamin D intake and/or status and infant and toddler 1) growth and physical development, 2) immune function, and 3) bone development?
    • What is relationship between LCPUFA intake and/or status and infant and toddler 1) growth and physical development, 2) cognitive, behavioral, or neuromotor development, 3) immune function, and 4) visual acuity?
    • What is relationship between fluoride intake and/or status and infant and toddler growth and physical development (bones, teeth)?
    • What is the relationship between vitamin B12 intake and/or status and infant and toddler 1) cognitive, behavioral, or neuromotor development and 2) risk of anemia?
    • What strategies can be used to improve dietary quality and micronutrient intake in infants 6-12 months of age and would different nutrients (e.g., iron, fluoride) require different strategies?
  • Appropriate complementary food choices for human milk, formula or mixed fed infants from a macro- and micro-nutrient standpoint
    • What is the optimal distribution of daily energy and macronutrient intake from complementary foods, human milk and/or infant formula (or a combination of the two) that promotes favorable health outcomes, such as 1) growth and physical development, 2) cognitive, behavioral or neuromotor development, 3) prevention of food allergies and asthma, and 4) prevention of overweight/obesity?
    • What types and amounts of complementary foods are necessary for infants fed human milk, formula, or mixed feedings to promote favorable health outcomes, such as 1) growth and physical development, 2) cognitive, behavioral or neuromotor development, 3) prevention of food allergies and asthma and 4) prevention of overweight/obesity?
  • Early dietary influences on food and flavor likes and dislikes especially for nutrient dense foods (fruits, vegetables, meat, diary, etc).  What are the evidence-based strategies to enhance acceptance of nutrient dense foods like fruits and vegetables?
    • Is there a relationship between appropriate/increased intake (quantity, timing, frequency) of nutrient dense foods (meats, dairy, fruits, vegetables, etc.) by the mother during pregnancy and acceptance/preference of nutrient dense foods in infants?
    • Is there a relationship between appropriate/increased intake (quantity, timing, frequency) of nutrient dense foods (meats, dairy, fruits, vegetables, etc) by the mother after infants’ birth on the acceptance/preference of nutrient dense foods by their children?
    • Are there differences in the acceptance/preference of nutrient dense foods between breast and formula fed infants?
    • Does exposure (timing, quantity, frequency) to nutrient dense foods in weaned infants increase acceptance of nutrient dense foods?
    • Are there differences in pattern or duration of acceptance between infants who were formula or breast or both during first few months of life and if so how does this relate to maternal diet and feeding practices?  Are there differences among formula-fed infants depended on the type of formula breastfed or formula fed infants in early life?
    • Does increased acceptance/preference for nutrient dense foods in the first year of life persist?  Does it improve dietary intake of nutrient dense foods at 12-24 months?  Does this impact on growth parameters during infancy and childhood?
  • Development of taste preferences for salt and sweet in infants and the impact on dietary intake and long term health outcomes.  How do preferences for foods with added salt and sugars develop?
    • Do infants and children differ in their preferences for sugar and salt? If there are differences, what are the mechanisms underlying these age related changes?  Are there differences among races? Genetics? Gender? Emotional state of the child (e.g., depression)?
    • Is there a relationship between health of the mother prenatally (e.g., hyperemesis gravidarum) and preference for salt and sweet?
    • Does the intake of foods with added salt and sugar in infancy influence the preference and analgesic appeal of dietary salt and sweet in infants, young children and adults?
    • Does repeated exposure of foods with added sugar lead to sugar “addiction” later in life (physiologic endorphin response)? How much of the addiction is pre-dispositioned and inborn versus. conditioned?
    • Is there a relationship in infants between intake of foods with added salt and sugar (timing of introduction, quantity, frequency) and preference for salt and sweet later in childhood and adulthood?  Does this impact on growth parameters at 12 to 24 months? Body composition/health Later in life?
  • The role, timing and value of snacking (i.e. food consumed between meals)
    • What is the association between scheduled vs. self-regulated snacking on infant and toddler 1) growth and physical development, 2) overweight/obesity and 3) dietary intake?
    • Are there differences between breast and formula fed infants?
    • What is the association between frequency of snacks and infant/ toddler’s 1) growth and physical development, 2) overweight/obesity and 3) dietary intake?
    • What snacks optimize nutrient intakes in infants and toddlers; and are there differences between breast and formula fed infants?
  • Method of complementary feeding
    • What is the relationship between adding solids to bottles and infant/toddler 1) oral health, 2) overweight/obesity and 3) dietary intake (e.g. macro- including calorie and micro-nutrient intake)?
    • What is the relationship between putting a baby to bed with a bottle and infant/toddler 1) oral health, 2) overweight/obesity and 3) risk of otitis media?
    • What methods of introducing solids results in optimal infant/toddler 1) oral health, 2) overweight/obesity and 3) dietary (quality and quantity) intake?
  • Impact of the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) food package on infant and child diet – The Work Group suggested that each of the following study questions be repeated, comparing new vs. old WIC food packages:
    • Is participation in WIC associated with improved breastfeeding initiation, duration and exclusivity?
    • With regard to complementary feeding, iIs participation in WIC associated with:
    •  Age at which infants are introduced to solid foods?
    • The types of first food introduced?
    • A specific pattern of complementary feeding during infancy (dietary pattern, types of foods consumed, added sugar and salt content of complementary foods, age in which whole milk is introduced)?
    • How do associations between WIC participation and infant and young child feeding differ for breast fed compared to formula fed infants?
    • How do associations between WIC participation and infant and young child feeding differ for children of different race and ethnic groups?
    • Is participation in WIC associated with childhood obesity or other diet-related adverse health outcomes?
    • Is participation in WIC associated with improved food security (compared to non-WIC, not WIC eligible and non-WIC, WIC eligible)?
The additional topic of physical activity in the prevention of childhood obesity was considered by this work group; however, questions were not drafted due to insufficient data to support any systematic reviews at this time.