The first few years of life set the foundation for brain health. Studies show that a nutritious diet in infancy is key to promoting a child's long-term well-being, and the foods they eat can impact their cognition, temperament, motor skills and language development.

As a nutritional psychiatrist, I've found that foods rich in omega-3 fatty acids, folate, iron, iodine, zinc, choline and vitamins A, B12 and D support brain function, behavior and learning. Avoiding processed foods with added sugars is also key.

Children can be picky, so parents will have to get creative. Here are six brain foods that will help your kids stay sharp and focused:

1. Superfood smoothies

Smoothies are a tasty way to incorporate lots of nutrients into your child's diet — and even disguise foods that they might normally fight. You can even call it a "milkshake."

For the best superfood smoothie, add folate-rich and fiber-rich leafy greens like spinach or kale, along with chia seeds or walnuts for plant-based omega-3 fatty acids, fiber and protein. Then throw in an avocado for healthy fats, followed by antioxidant-rich blueberries.

Adding plain, unsweetened yogurt can also increase your smoothie's creaminess, protein levels and gut-healthy probiotics that boost mood.

2. Homemade veggie fries

Eating a colorful variety of vegetables is so important for getting enough fiber and phytonutrients, as well as fueling both gut health and mental health.

Air fryer ovens add a crispy, crunchy texture to food without deep frying. Use it to make zucchini, carrot or green bean "fries."

Then top the vegetables with a pinch of black pepper and turmeric, rosemary, oregano, parsley or thyme to add flavor.

3. Homemade hummus

Legumes are healthy, plant-based sources of iron, zinc, protein and fiber, benefitting brain development.

Homemade hummus is a versatile way to incorporate legumes into your child's diet. It can be served in so many ways, such as a dip paired with apple slices, carrot sticks, thinly sliced celery or sugar snap peas.

Adding some color to your hummus can make it more appealing to kids. Think: a bright orange carrot hummus or a deep-purple beet hummus topped with a monster face made out of vegetables.

4. Salmon

Introducing your child to fish at a young age can increase their likelihood of enjoying it and eating low-fat, vitamin-rich proteins for the rest of their life.

Salmon is soft and mild enough for young children, and is also a good source of vitamin B12 and omega-3s, which promote healthy brain development and happier moods.

5. Eggs

Whole eggs are an excellent source of brain-boosting vitamins A, D and B12, along with choline. Choline is especially important for young children, as it has been shown to improve brain development and long-term memory.

I recommend buying pastured eggs: One study found that pastured eggs can have twice as much vitamin E and almost three times as many omega-3s as caged eggs.

6. Meatballs

Sneak some powerful plant-based fiber and nutritious veggies into your child's diet through meatballs.

Start with a base of beans, lentils or pastured ground turkey. Then add shredded spinach or grated zucchini.

Use flax seeds to bind the ingredients for added omega-3s and toss in your spices. Baking the meatballs, versus frying, is the healthiest way to do it.

Dr. Uma Naidoo is a nutritional psychiatrist, brain expert, and faculty member at Harvard Medical School. She is also the Director of Nutritional & Lifestyle Psychiatry at Massachusetts General Hospital and author of the best-selling book "This Is Your Brain on Food: An Indispensable Guide to the Surprising Foods that Fight Depression, Anxiety, PTSD, OCD, ADHD, and More." Follow her on Twitter and Instagram.

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