Exclusively breastfeeding babies for 3-6 months may help them maintain healthier eating habits as they grow, according to a 2026 cohort study of 135,340 Brazilian children. Breastfed children eating fewer ultra-processed foods were 11% more likely to keep those eating habits at preschool age and 10% less likely to switch to junk food. Gram Research analysis shows that early feeding choices appear to shape food preferences that persist through childhood.
A major study tracking over 135,000 Brazilian children from 2008 to 2019 found that babies who were exclusively breastfed for 3-6 months were more likely to eat healthier foods as preschoolers and less likely to switch to ultra-processed foods. The research shows that eating habits formed in early childhood tend to stick around as kids grow older. According to Gram Research analysis, exclusive breastfeeding appears to give children a protective advantage against developing a preference for highly processed foods during their early years.
Key Statistics
A 2026 cohort study of 135,340 Brazilian children found that exclusively breastfed children eating fewer ultra-processed foods had 11% higher odds of maintaining that healthier pattern at preschool age compared to other children.
According to research reviewed by Gram, exclusively breastfed children in lower ultra-processed food patterns had a 10% lower likelihood of transitioning to high ultra-processed food diets by preschool age.
A Brazilian Food and Nutritional Surveillance System analysis tracking 135,340 children from 2008-2019 found that dietary patterns remained notably stable from early childhood through school age, suggesting habits formed early tend to persist.
The Quick Take
- What they studied: Whether the way babies are fed (especially breastfeeding) affects what foods they eat as they grow up, and whether eating habits stay the same or change over time.
- Who participated: Over 135,000 Brazilian children tracked from ages 1 to 11 years old using data collected between 2008 and 2019 through a national food and nutrition tracking system.
- Key finding: Children who were exclusively breastfed for 3-6 months were 11% more likely to stick with healthier eating patterns (lower ultra-processed foods) as preschoolers, and 10% less likely to switch to eating more junk food.
- What it means for you: If you’re a parent, breastfeeding your baby for at least 3-6 months may help set them up for healthier eating habits throughout childhood. However, this doesn’t mean formula-fed babies can’t develop healthy eating habits—many other factors influence what kids eat.
The Research Details
Researchers used information collected over 11 years from Brazil’s national food and nutrition tracking system. They looked at what 135,340 children ate at three different ages: toddlers (1-3 years old), preschoolers (3-6 years old), and school-age children (6-11 years old). Instead of looking at individual foods, they identified two main eating patterns: one where kids ate lots of ultra-processed foods (like packaged snacks and sugary drinks) and one where they ate fewer of these foods. They then tracked whether children stayed in the same eating pattern as they got older or switched to a different pattern.
The researchers used a special statistical method called Latent Transition Analysis, which is like following a path through a maze—it shows how kids move from one eating pattern to another over time. They specifically looked at whether children who were exclusively breastfed (meaning they only got breast milk, no formula or other foods) for 3-6 months had different eating patterns than other children.
This approach is important because it looks at real-world eating habits of a huge number of children over many years, rather than just taking a snapshot at one moment in time. By following the same children as they grow, researchers can see if early feeding choices actually affect what kids eat later. This helps us understand whether breastfeeding has long-lasting effects on children’s food preferences.
This study is strong because it includes a very large number of children (over 135,000) from an entire country’s tracking system, which means the results likely represent real patterns in the population. The data was collected consistently over 11 years using standardized methods, which makes it reliable. However, the study can only show that breastfeeding and healthier eating patterns are connected—it cannot prove that breastfeeding directly causes healthier eating, since many other family factors also influence what children eat.
What the Results Show
The study found that children’s eating patterns were quite stable as they grew from toddlers to school age. Most children who ate fewer ultra-processed foods as toddlers continued eating that way as preschoolers and school-age children. Similarly, children who ate lots of ultra-processed foods tended to keep eating that way.
The most important finding involved breastfeeding. Children who were exclusively breastfed for 3-6 months and were eating fewer ultra-processed foods as toddlers had an 11% higher chance of maintaining that healthier eating pattern when they reached preschool age. This means breastfeeding seemed to help lock in good eating habits. On the flip side, exclusively breastfed children eating fewer ultra-processed foods were 10% less likely to switch to eating more junk food as they got older.
These percentages might sound small, but when you apply them to millions of children, they represent a meaningful difference in public health. The study suggests that the early months of life—when breastfeeding happens—may be a critical window for shaping lifelong eating habits.
The research also showed that dietary patterns were remarkably consistent across the three age groups studied. Children’s eating habits didn’t change dramatically as they aged, which suggests that the foundation for food preferences is set very early in life. This finding supports the idea that what happens in the first few years matters a lot for long-term health.
Previous research has suggested that breastfeeding has many health benefits, but this study adds important evidence that those benefits may extend to eating habits years later. Most earlier studies looked at breastfeeding and health outcomes separately, but this research shows a direct connection between how babies are fed and what they choose to eat as they grow. The stability of eating patterns found here aligns with other research showing that childhood habits tend to persist into adulthood.
The study can show that breastfeeding and healthier eating patterns go together, but it cannot prove that breastfeeding causes healthier eating. Many other factors influence what children eat, including family income, education, food availability, and cultural preferences. The study didn’t measure all of these factors, so some of the connection might be due to other differences between families who breastfeed and those who don’t. Additionally, the data comes only from Brazil, so results might be different in other countries with different food systems and cultures.
The Bottom Line
If you’re planning to have children or are a new parent, the evidence suggests that exclusive breastfeeding for at least 3-6 months may help establish healthier eating patterns that last into childhood. However, this doesn’t mean formula feeding leads to poor eating habits—many other parenting choices matter too, such as offering a variety of whole foods, limiting sugary drinks, and modeling healthy eating yourself. (Confidence: Moderate—the study shows a connection but cannot prove cause and effect.)
This research is most relevant to parents and caregivers of young children, pediatricians, and public health officials designing nutrition programs. It’s particularly important for families in countries like Brazil where ultra-processed food consumption is rising. If you’re unable to breastfeed, this doesn’t mean your child will develop poor eating habits—focus on the foods you introduce as your child grows.
The effects of breastfeeding on eating patterns appear to show up by preschool age (3-6 years old) and continue through school age. Don’t expect immediate changes; the benefits emerge over months and years as children develop their food preferences.
Frequently Asked Questions
Does breastfeeding affect what foods my child will eat later?
Research suggests yes. A study of 135,340 Brazilian children found that exclusively breastfed babies were more likely to maintain healthier eating patterns and less likely to switch to ultra-processed foods as they grew older, though other family factors also matter.
How long should I breastfeed to see benefits for my child’s eating habits?
The study found benefits from exclusive breastfeeding for 3-6 months. However, any breastfeeding is beneficial, and formula-fed children can develop healthy eating habits through other parenting choices like offering whole foods early.
Can eating habits change after early childhood?
While the study found eating patterns are quite stable from age 1 to 11, habits can still change. Introducing new foods, modeling healthy eating, and limiting ultra-processed options can help shift patterns at any age.
What counts as ultra-processed food I should limit for my child?
Ultra-processed foods include packaged snacks, sugary cereals, sweetened drinks, fast food, and candy. Focus on whole foods like fruits, vegetables, whole grains, and proteins instead.
If I couldn’t breastfeed, will my child eat unhealthy foods?
Not necessarily. Breastfeeding is one factor among many. What matters most is what foods you offer as your child grows, how you model eating habits, and your family’s overall food environment.
Want to Apply This Research?
- Log your child’s daily food intake weekly, categorizing foods as ‘whole foods’ (fruits, vegetables, grains, proteins) versus ‘ultra-processed’ (packaged snacks, sugary drinks, fast food). Track the percentage of ultra-processed foods consumed each week to see if patterns shift over months.
- If your child is eating many ultra-processed foods, gradually introduce one new whole food per week and reduce one ultra-processed item. For example, replace sugary cereal with oatmeal, or swap chips for apple slices. Track these swaps in the app to monitor progress.
- Review eating patterns every 3 months to identify trends. Set a goal to reduce ultra-processed food intake by 10% every quarter. Use the app to celebrate weeks where your child ate more whole foods, reinforcing positive habits.
This research shows an association between breastfeeding and healthier eating patterns but cannot prove that breastfeeding directly causes these patterns. Many factors influence children’s eating habits, including family income, food availability, and parental modeling. Parents unable to breastfeed should not feel their children are at a disadvantage—focus on offering nutritious whole foods and creating a healthy food environment. Always consult with your pediatrician about your child’s nutrition and feeding choices. This article is for educational purposes and should not replace professional medical advice.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.