A new review shows that what kids eat during early childhood has a huge impact on how their brains develop. Both eating too little and eating too much can cause problems with thinking, emotions, and learning. Missing important nutrients like iron and iodine can slow brain growth, while eating too many calories might cause inflammation in the brain. The effects are strongest before birth and in the first few years of life, and they can last into adulthood, affecting school performance and behavior. The good news is that fixing nutrition problems early on can help prevent long-term brain and mental health issues.

The Quick Take

  • What they studied: How eating too little food (undernutrition) or too much food (overnutrition) affects how children’s brains grow and work
  • Who participated: This was a review article that looked at many different studies about nutrition and brain development in children, rather than studying one specific group of people
  • Key finding: Both eating too little and eating too much can harm brain development, especially before birth and in early childhood. Missing key nutrients like iron, iodine, folate, and vitamin B12 particularly damages how the brain grows, while eating too many calories may cause swelling and damage in the brain
  • What it means for you: Parents and caregivers should aim to give children balanced meals with the right amount of food and important nutrients during pregnancy and the first few years of life. This can help kids develop better thinking skills, emotional control, and mental health as they grow up

The Research Details

This is a review article, which means researchers looked at many existing studies about nutrition and brain development and summarized what they found. Instead of doing their own experiment with people, they gathered information from other scientists’ work to see what patterns and connections exist between food and how children’s brains develop.

The researchers focused on two main nutrition problems: undernutrition (not eating enough food or missing important nutrients) and overnutrition (eating too many calories). They looked at how these problems affect different parts of brain development, including thinking skills, emotions, and mental health.

They paid special attention to the most important times for brain development: before a baby is born and during the first few years of life. They also looked at how nutrition problems can have lasting effects that continue into adulthood.

Review articles like this are important because they bring together information from many different studies to show us the big picture. Instead of relying on just one study, which might have been done with a small group of people, reviews help us understand what most scientists agree on. This type of research is especially useful for understanding complex topics like how nutrition affects brain development, because no single study can show everything we need to know.

This review was published in a respected medical journal called Seminars in Pediatric Neurology, which means experts checked the work before it was published. However, because this is a review of other studies rather than original research, the quality depends on the studies it includes. The researchers looked at current scientific knowledge, which is good, but readers should know that some of the studies they reviewed might have different quality levels. The review focuses on well-established nutrition problems, which makes the findings more reliable.

What the Results Show

The research shows that nutrition during early brain development is extremely important. The brain is like a construction project that happens mostly before birth and in the first few years of life, and it needs the right materials (nutrients) to build properly.

When children don’t get enough food or are missing important nutrients, their brains don’t grow as well. Specific nutrients that are especially important include iron (which helps the brain use oxygen), iodine (which helps the brain work properly), folate (which helps build brain cells), and vitamin B12 (which protects brain cells). Without these nutrients, children may have trouble thinking, learning, and controlling their emotions.

Interestingly, eating too much food is also a problem. When children eat too many calories, it can cause swelling in the brain and change how brain circuits work. This can also hurt thinking skills and emotional health.

The damage from poor nutrition during early childhood doesn’t just go away. Children who had nutrition problems when they were young often have trouble in school, behavior problems, and mental health issues later in life.

Beyond the direct effects on brain development, the review highlights that nutrition problems have bigger impacts on families and communities. When children don’t develop their brains fully, they may not do as well in school, which can affect their jobs and income as adults. This creates a cycle where poor nutrition leads to less education, which leads to less money, which can mean more poor nutrition for the next generation. The review also notes that these problems are especially serious in poorer communities and countries where people don’t have enough money for healthy food.

This review brings together what scientists have learned over many years about how nutrition affects the brain. Previous research has shown that specific nutrients are important for brain development, and this review confirms those findings while also adding new information about how eating too much food can be harmful. The review shows that scientists now understand that nutrition affects not just whether the brain grows big enough, but also how well it works and how it affects behavior and emotions.

Because this is a review of other studies rather than original research, it depends on the quality of those studies. Some of the research it includes might have been done with small groups of people or in specific countries, so the findings might not apply equally to everyone. The review also focuses mainly on severe nutrition problems (very little food or very much food), so we might not know as much about mild nutrition problems. Additionally, the brain is very complex, and it’s hard to study exactly how nutrition affects it in real people, so some connections might not be fully understood yet.

The Bottom Line

Make sure children, especially before birth and in the first few years of life, eat a balanced diet with enough calories and important nutrients like iron, iodine, folate, and vitamin B12. This is strongly supported by research (high confidence). Avoid both eating too little and eating too much processed food with lots of calories but few nutrients. Parents and communities should work together to make sure all children have access to healthy food. Governments and health organizations should monitor nutrition in communities, especially in poorer areas where nutrition problems are more common.

Parents and caregivers of young children should pay attention to these findings, especially pregnant women and families with children under age 5. Teachers and school officials should care because nutrition affects learning. Healthcare providers should use this information to help families. Government and public health officials should care because fixing nutrition problems helps entire communities. People in low-income countries and poor communities should especially focus on this, as they face higher risks of nutrition problems. This information is less directly relevant to adults whose brains have already fully developed, though good nutrition is still important for overall health.

The effects of good nutrition happen gradually. During pregnancy and the first few years of life, good nutrition helps the brain build properly, but you won’t see the full benefits until children start school and you can see how well they learn and behave. Some benefits appear within months (like better energy and focus), but the biggest benefits show up over years and decades as children grow up, do better in school, and have better mental health. If nutrition problems have already happened, fixing them now can still help, but the earlier you start, the better.

Want to Apply This Research?

  • Track your child’s daily food intake by logging meals and snacks, noting whether they include key nutrients (iron-rich foods like meat or beans, iodine-rich foods like dairy or fish, folate-rich foods like leafy greens, and B12-rich foods). Rate meals on a simple scale: ‘Balanced’ (has protein, vegetables, whole grains, and healthy fats), ‘Needs More Nutrients’ (missing some food groups), or ‘Too Many Calories’ (mostly processed foods). Aim for 80% ‘Balanced’ meals per week.
  • Use the app to set a weekly meal plan that includes at least one iron-rich meal, one iodine-rich meal, one folate-rich meal, and one B12-rich meal per day. Set reminders to offer healthy snacks instead of processed foods. Track your child’s energy levels and focus during the day to see if better nutrition improves behavior and attention. Use the app’s recipe suggestions to make it easier to plan balanced meals.
  • Check in monthly to see if your child’s meals are more balanced. Look for patterns: Are certain nutrients missing? Is your child eating too many processed foods? Use the app to track changes in your child’s behavior, energy, and school performance over 3-6 months to see if better nutrition is helping. Share this information with your child’s doctor at regular check-ups to make sure your child is growing and developing well.

This review summarizes scientific research about how nutrition affects brain development in children. It is not medical advice for your individual child. Every child is different, and nutrition needs vary based on age, health, and other factors. If you have concerns about your child’s nutrition, growth, or development, please talk to your child’s doctor or a registered dietitian. This information is meant to help you understand the importance of good nutrition, not to diagnose or treat any health condition. Always consult with healthcare professionals before making major changes to your child’s diet, especially if your child has any health conditions or takes medications.