In a recent study published in the Journal of the Academy of Nutrition and Dietetics, researchers determined the association between the duration of breastfeeding and the intake of ultra-processed food items (UPF) among preschool children in Spain.

Study: Longer breastfeeding duration is associated with lower consumption of ultra-processed foods in a sample of Spanish preschoolers: The SENDO project. Image Credit: Nastyaofly/Shutterstock.com

Background

Breastfed infants reportedly consume more fruits and vegetables than formula-fed infants. Studies have reported that breastfeeding may lower pediatric consumption of UPF, formulations of ingredients created from substances derived from food components to which additives are added.

UPF production involves biological, chemical, and physical industrial processes that result in ready-to-eat products requiring minimal food preparation, making them readily accessible but poor in nutritional value.

Increased UPF consumption has shifted dietary patterns from the conventional Mediterranean diet comprising largely plant-based foods to Western diets involving low fruit and vegetable intake.

Increased UPF intake has been associated with hypertension, obesity, and mortality. Identifying factors associated with lower UPF intake during childhood is critical to preserving pediatric well-being and preventing adverse outcomes from excessive UPF intake.

About the study

In the present cross-sectional study, researchers evaluated the impact of breastfeeding duration on UPF consumption among Spanish preschoolers.

Data from 806 four-to-five-year-old Seguimiento del Niño para un Desarrollo Óptimo (SENDO) study participants were analyzed in Spain and enrolled from January 2015 to June 2021. Data were obtained via web-based questionnaires filled out by their parents.

In addition, dietary data were obtained using food frequency questionnaires (FFQs), and the food items were classified using the NOVA system.

The study outcomes were (i) the difference in grams daily and in the proportion of total energy intake (TEI) from UPF intake associated with the duration of breastfeeding and (ii) the odds of UPF representing a high proportion of total energy intake (TEI). The team calculated crude and adjusted multivariate odds ratios (OR) using generalized estimating equations (GEE).

The average daily screen time was calculated for all participants. Parental knowledge of pediatric nutritional guidelines and their attitudes toward their child’s dietary habits were also assessed.

Individuals without access to internet-connected devices were excluded. Data extracted included participant birth date, race, sex, maternal educational attainment, prenatal, perinatal, and postnatal periods, and lifestyle-related factors such as sedentary habits and physical exercise.

Participants’ body mass index (BMI) values were determined and used to evaluate their nutritional status using the International Obesity Task Force (IOTF) guidelines.

Results

Among the study participants, 84% (n=681) were breastfed, 31% (n=252) for less than six months, 26% (n=209) for six to 12 months, and 27% (n=220) for ≥12 months.

Children who received breast milk for a longer duration were more often the eldest sibling and were vaginally born with greater birth weight. Premature births were lower among children who were breastfed for longer durations.

Well-educated mothers breastfed their children for longer durations, and mothers who breastfed their children for longer possessed more knowledge of the nutritional recommendations for children and showed healthier attitudes towards the dietary habits of their offspring.

The duration of breastfeeding correlated inversely with the intake of UPF, including ultra-processed meat, fast food, chocolate, and dairy products such as custards and smoothies, during early childhood.

Children receiving breast milk for ≥1.0 years documented 6.50% lesser calorie intake from UPF at five years of age than formula-fed children. The mean differences observed were -19 grams, -43 grams, and -44 grams for four-to-five-year-olds receiving breast milk for less than six months, six to 12 months, and ≥12 months, respectively.

The adjusted estimates indicated that compared to formula-fed children, those who received breast milk for ≥1.0 years showed a lower likelihood of UPF comprising more than 25.0%, 30.0%, 35.0%, and 40.0% of TEI.

Similar results were obtained in the sensitivity analysis performed by excluding 182 participants with excessive caloric intake, and the findings were concordant with previous studies.

Conclusions

Based on the study findings, the duration of breastfeeding is related to lower UPF intake among preschoolers in Spain. Further research is required to elucidate the mechanisms underlying the association between breastfeeding duration and UPF intake and to evaluate the impact of breastfeeding promotion campaigns on the dietary habits of preschoolers.

Early exposure to different flavors favor a greater predisposition to healthy products (i.e., vegetables and fruits) in infancy. Unlike formula milk, the taste of human milk can change with the maternal diet.

Thus, breastfed children are exposed to a wider variety of flavors than formula-fed ones, which may increase the acceptance of foods often rejected by infants, including vegetables and fruits.