Key Nutrients for Kids: Age-by-Age Guide

Making sure you know the right nutrients for kids—and ensuring they get those nutrients—will help your little ones learn, grow, and develop. For many, this simply involves breastfeeding or formula-feeding in infancy, followed by eating a varied and balanced diet in the toddler years and beyond. But for kids with extreme pickiness or health issues that impact their ability to eat or use nutrients, supplements—or even a feeding tube—could be required to stay well nourished.

Your pediatrician, along with a pediatric registered dietitian nutritionist (RDN), can help you understand your child’s unique nutritional requirements. They also can advise you on what tools you can use to help them get the vitamins and minerals their bodies need to thrive. But, as a general rule, here are the top nutrients for kids at every age.

Are Your Kids Consuming Enough of These Essential Nutrients?

While kids need numerous vitamins and minerals, six key nutrients are especially important to be getting daily. These include vitamin D, iron, omega-3s, zinc, calcium, and potassium. Here’s how to ensure your child is consistently getting these nutrients.

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Vitamin D

Vitamin D supports bone health at all ages. In the early years, it helps build strong bones that benefit kids for life. It also reduces inflammation and improves immunity.

While we can get vitamin D from food and supplements, our bodies also produce vitamin D from sunlight exposure. Those with darker skin and people who don’t get a lot of natural sunlight may be more likely to need vitamin D from sources other than the sun. Vitamin D is found in trout, salmon, vitamin D-fortified milk, plant-based milk, and fortified cereal.

0-6 months: Shortly after birth, infants fed human milk—as well as formula-fed infants who consume less than 27 ounces of formula per day—need to be started on a vitamin D supplement that provides at least 400 IU per day, says Amy Reed, MS, RD, a pediatric dietitian at Cincinnati Children’s Hospital Medical Center. “In the first 6 months of life, human milk can provide all nutrient needs except for Vitamin D.”

Infants: Because it can be difficult to get enough vitamin D from food sources, Reeds says infants older than 6 months may continue to need a supplement. Talk to your child’s pediatrician to see what is best for your child. Again, children younger than 12 months need 400 IU per day, says the CDC, and this increases to 600 mg after 12 months.

Toddlers and young children: As kids get older, they typically eat more foods that contain vitamin D. As a result, they may not need a supplement, says Reed. However, it’s still a good idea to talk to your child’s pediatrician to understand their needs.

Older children and teenagers: The recommended amount of vitamin D is 600 IU per day, but older children will sometimes get their vitamin D level checked to ensure they’re getting enough. If your provider finds your child’s vitamin D level is low, they may recommend supplementation.


This mineral carries oxygen in the red blood cells to help the body produce energy. When iron levels are low, a person may feel weak or tired. Babies in particular need iron for brain development and growth.

Iron is found in meat, seafood, poultry, spinach, beans, and fortified cereals. Eating iron-containing foods with a source of vitamin C like citrus fruit, broccoli, and red bell peppers can help increase your child’s iron absorption.

0-6 months: Most newborns have gained enough iron stores for about the first 6 months of life.

Infants: At 6 months, your child’s iron needs increase from 0.27 mg per day to 11 mg per day, says Reed. This is the perfect time to introduce foods that are good sources of iron like iron-fortified cereals, meats, and beans. Iron deficiency can lead to slower development and physical symptoms like irritability and slow weight gain.

Toddlers and young children: Between the ages of 1 and 3, your child needs 7 mg per day, and 10 mg per day between the ages of 4 and 8. Too much cow’s milk at this age can crowd out other foods, resulting in a child not getting enough iron, says Reed. Limit your little one to no more than 20 ounces of cow’s milk per day once they reach toddlerhood.

Older children and teenagers: Keep in mind that, around age 9, kids often start to decrease their intake of protein-rich foods that are also good sources of iron. But iron continues to be important for healthy development—especially for teenage girls who experience monthly blood loss from menstruation, says Reed.


Omega 3s are an essential fatty acid, and they’re especially important for kids’ brain health, says Marina Chaparro, MPH, RDN, a diabetes educator and founder of Nutrichicos, a bilingual pediatric nutrition practice in Miami. They’re one of the key nutrients needed for the rapid brain development that happens in the first 2 years of life, says Chaparro.

After the first 2 years, omega-3s remain important for the central nervous and cardiovascular systems, as well as healthy eye function. You can find omega 3s in salmon, sardines, herring, mackerel, walnuts, flaxseeds, chia seeds, and canola oil.

0-6 months: Human milk contains the omega-3 known as DHA, as do most commercial infant formulas. Other sources include ALA (mostly found in plants) and EPA. From 0 to 12 months, your baby needs 0.5 grams of omega-3 per day.

Infants: Babies this age will still get some omega-3s through human milk and formula. Introducing foods like fish and muffins baked with flaxseed can help them develop a taste for foods that include omega-3s as well.

Toddlers and young children: From 1 to 3 years, your little one needs 0.7 grams per day. And between 4 and 8 years it increases to 0.9 grams per day. Snacking on chia pudding, adding flaxseed oil to smoothies, and having salmon burgers for dinner are all kid-friendly ways of getting in omega-3s.

Older children and teenagers: After 9 years of age, your child’s need for omega-3s increases to more than 1 to 1.6 grams per day. Continue to look for ways to add omega-3s to their diet.


This mineral is required for healthy growth and development. The immune system, in particular, needs zinc to function and to help with wound healing. It also plays a role in the sense of taste and smell. Zinc is available in meats, dairy, fish, shellfish, legumes, and fortified cereals.

0-6 months: At this age, human milk and formula provide an adequate amount of zinc. However, if you are concerned about your child’s intake, discuss their nutrition with their pediatrician. Babies 0-6 months need 2 mg per day.

Infants: According to Reed, the amount of zinc in human milk can decrease, says Reed. If your baby is mostly consuming human milk, be sure to offer complementary foods that are good sources of zinc starting at 6 months of age. Babies aged 7–12 months need 3 mg of zinc per day.

Toddlers and young children: If your child has a varied diet, they will typically eat enough zinc, says Reed. “But, if children are vegetarian, they may need to consume higher amounts of plant-based sources of zinc or zinc-fortified grains to achieve adequate intake.” Kids ages 1–3 years need 7 mg daily, and those 4–8 years require 12 mg.

Older children and teenagers: While adequate zinc intake is still important, it was not identified as a nutrient concern for this age group by the 2020-2025 U.S. Dietary Guidelines, says Reed. However, you can always talk to a health care provider if you have concerns.


While calcium plays a variety of roles in the body, it’s best known for helping build strong bones and teeth. Up to 90% of your child’s peak bone mass will be built before they hit their 20s—meaning the early years are the most important time to build bone density. Cow’s milk, yogurt, cheese, almonds, broccoli, kale, spinach, and fortified plant-based milk are all good sources of calcium.

0-6 months: Babies at this age get the calcium they need through human milk or formula. If you are concerned about your baby’s intake of human milk or formula, make sure you talk to your child’s pediatrician.

Infants: Your baby’s calcium needs increase after 6 months. However, children under 1 year of age should still not drink cow’s milk to meet those needs. The calcium in human milk and formula, as well as complementary foods that are appropriate for this age like yogurt, tofu, and broccoli, can help meet those needs.

Toddlers and young children: At ages 1-3, children need 700 mg of calcium per day—and this increases to 1,000 mg for those ages 4-8, says Reed. Cow’s milk is one possible source since it contains 300 mg of calcium per eight-ounce glass. But drinking milk isn’t necessary—calcium is also available in foods like cheese and yogurt, as well as non-dairy sources like leafy greens, almonds, fortified plant-based milks, and tofu.

Older children and teenagers: Calcium is especially important at this age because it’s when your child’s body is storing calcium to ensure strong bones for decades to come. At age 9, the recommended calcium intake increases from 1,000 to 1,300 mg per day. “This is also the age that intake of dairy foods decreases,” says Reed.


This electrolyte mineral helps nerves to function and muscles to contract, and it plays a role in ensuring your heartbeat stays regular. It also helps maintain normal levels of fluid inside our cells and can flush sodium from the body, counteracting some of that mineral’s harmful effects on blood pressure.

Most of the time, a balanced diet is enough to maintain healthy potassium levels. However, if your child loses fluid through vomiting or diarrhea, talk to your pediatrician about how to meet their increased needs for this electrolyte. Potassium is found in oranges, grapefruits, melons, grapes, spinach, potatoes, bananas, lentils, dried fruit, winter squash, sweet potatoes, and milk.

0-6 months: Human milk and infant formula should contain the right balance of potassium for a baby this age; they need 400 mg per day. As always, though, talk to your child’s pediatrician if they are vomiting or have diarrhea. They may ask you to increase feedings to meet their needs.

Infants: According to the 2020-2025 Dietary Guidelines for Americans, potassium is a nutrient of concern for older infants, who need about 860 mg daily. As you add in supplementary foods, be sure you are including plenty of produce—bananas, melons, and oranges are all good sources of potassium that can be safely introduced at this age.

Toddlers and young children: Potassium continues to be an important nutrient at this age. Fruits and vegetables are important sources. However, whole grains and dairy foods which are part of a balanced diet also provide potassium. Potassium needs range from 2,000 mg for ages 1-3 to 2,300 mg for ages 4-8.

Older children and teenagers: This mineral is crucial for very active kids who are losing sweat, says Chaparro. Eating and drinking foods high in potassium helps maintain proper fluid balance, she says, especially during periods of high activity or hot weather.