To our knowledge, ours is the first study demonstrating the frequency and types of nutrient supplementation of Latino infants at 4 to 6 weeks of age. The AAP recommends exclusive breastfeeding during the first 6 months of life to minimize the incidence or severity of diarrhea, ear infections, and bacterial meningitis.3
The academy also suggests that breastfeeding may offer protection against sudden infant death syndrome, diabetes, obesity, and asthma. Early supplementation of infants with water, teas, or other liquids is not recommended by the AAP or the WHO, because of the nonnutrient values of these beverages, the solute load of juice, the possibility of introduction of contaminants or allergens, and the possibility that these liquids will displace breastfeeding.3
The academy policies state that healthy infants require no supplemental water, even in hot weather, because both formula and breast milk provide sufficient amounts of water.3
Water supplementation has also been associated with oral water intoxication in infants.6,31
At 4 to 6 weeks, 38% of our population was exclusively breastfeeding, which is slightly lower than the national average for exclusive breastfeeding in the United States at 4 weeks in 2007 (44.8%)32
and is comparable to rates from Mexico, where 39% of infants are exclusively breastfeeding at 4 weeks of age, on the basis of data from the 1999 national nutrition survey.33
We found that approximately one-fourth of our population was supplementing infants with water or tea and that the majority of these supplements were provided daily, primarily in 1-oz portions. However, a noteworthy percentage of women (27%) were supplementing with a larger portion size, ranging from 2 to 4 oz of water or tea, with the daily volume reaching up to 6 oz.
Ours is the first study to investigate early infant supplementation in a population of exclusively Latino infants. Although our sample had approximately 60% of mothers of Mexican origin and 40% from Central America and South America, multivariate analysis did not reveal any difference in the prevalence of infant supplementation based on maternal ethnicity. Given the increasing size of the Latino population group in California and the United States in general and the possibility of micronutrient deficiencies from a diet of insufficient amounts of breast milk combined with supplementation of water or tea, this is an important group to target for early nutritional educational and community intervention programs.
Additionally, we document the association between postnatal depressive symptoms and risk for early infant supplementation of tea and water. Postpartum depressive symptoms have been found to be associated with adverse child health and developmental outcomes, including poorer regulation of negative affect, less compliance, attachment insecurity, and less interest in being able to master the world of objects.34
Postnatal depressive symptoms are also associated with a lower breastfeeding rate,35
increased risk for failure to thrive,36
and reduced infant weight gain.37
Further studies are now indicated to determine the role that early supplementation of nonnutritive liquids such as water and tea may have in initiating unhealthy feeding practices that contribute future weight gain trajectories and potential overnutrition and undernutrition in Latino children.
Other studies that evaluated the early introduction of infant formulas in US populations found a similar rate of supplementation (24.7%)17
or a slightly higher rate (33.3% at 7–10 days postpartum).11
Studies of supplementation in Mexico have also found a high rate of infant supplementation, with 33.3% receiving water, teas, or nonbreast milks in the first week of life.38
However, these studies did not provide detailed information about the frequency of supplementation and the amount. The majority of mothers in our population who were supplementing their infants with teas and water were providing daily supplementation of these items. Ninety-one percent of women were providing, at minimum, daily supplementation formulas. Because this population is at particularly high risk for future obesity and the possibility of overnutrition with excessive use of infant formulas, future education and intervention efforts are needed in this area. Additionally, given the high percentage of participation in the WIC program in our cohort, educating mothers regarding early water and tea supplementation of breast-fed and formula-fed infants is an important area that WIC program providers should address.
We also found an increased association between early supplementation with teas and water and cesarean section delivery. Similarly, a study by Giugliani et al of intake of water, herbal teas, and nonbreast milks in the first month of life in Brazil found that children who received water or herbal teas in the first 7 days-of-life were more likely to have introduced nonbreast milks in the first month.39
This study also found that children who received water or teas in the first 7 days-of-life were 3 times more likely than other children to receive nonbreast milks by 4 weeks-of-age. Future interventions should target women who delivered via cesarean as a higher risk group for early infant supplementation.
This study has some inherent limitations. For a prospective cohort study, we can identify only associations but not causal relationships between supplementation and patient characteristics. Additionally, even with 192 study participants, we were under-powered to examine the role of clinical depression in relation to early infant supplementation; that is, only 4.2% of our sample had clinical depression as determined by the Mini International Neuropsychiatric Interview at 4–6 weeks postpartum. Maternal depressive symptoms and clinical depression were identified by screening measures and structured clinical interviews rather than clinical interviews by mental health professionals. Finally, because this study was conducted in the San Francisco Bay Area, its generaliz-ability to Latino populations elsewhere in the United States and abroad may be limited.
In summary, we report a high prevalence of water and tea supplementation in our population of Latina women. Supplementation appears to be increased in mothers with symptoms of postnatal depression and those who had a cesarean delivery. Of note, the risk factors in our population for supplementation of tea and water were different from those for use of infant formula. We did not find any risk factors associated with use of infant formulas. We recommend additional patient education on the advantages of exclusive breast-feeding and the potential risks of early water and tea supplementation, with materials in Spanish in particular.