Infant Nutrition: The First 6 Months

Medically Reviewed by Amita Shroff, MD on August 30, 2022
4 min read

Your baby is about to go through an amazing growth spurt. Expect your baby to double his or her birth weight by about age 5 -6 months and triple their birth weight by a year of age.. To grow that much, they need a lot of nutrients -- more than at any other time in their life.

Experts say breast milk is the best source of nutrition for babies during the first 6 months, but formula can be a good alternative.

Some of the nutrients babies need to grow and stay healthy include:

Calcium. Helps build strong bones and teeth.

Fat. Creates energy, helps the brain develop, keeps skin and hair healthy, and protects against infections.

Folate. Helps cells divide.

Iron. Builds blood cells, and helps the brain develop. Breast-fed babies should receive iron supplements.

Protein and carbohydrates. They provide energy and fuel growth.

Zinc. Helps the cells grow and repair themselves

Your baby also needs vitamins such as:

  • Vitamin A. Keeps skin, hair, vision, and the immune system healthy.
  • Vitamin B1 (thiamine). Helps the body turn food into energy.
  • Vitamin B2 (riboflavin). Helps the body turn food into energy, and protects cells from damage.
  • Vitamin B3 (niacin). Helps the body turn food into energy and use fats and protein.
  • Vitamin B6. Keeps the brain and immune system healthy.
  • Vitamin B12. Keeps nerve and blood cells healthy, and makes DNA -- the genetic material in every cell.
  • Vitamin C. Protects against infections, builds bones and muscles, and helps wounds heal.
  • Vitamin D. Helps the body absorb calcium from food, and keeps bones and teeth healthy. Breast-fed babies may need a D supplement.
  • Vitamin E. Protects cells from damage, and strengthens the immune system.
  • Vitamin K. Helps the blood to clot.

Most infant formulas today are made from cow's milk. They are fortified to make them as close to breast milk as possible, and to give babies all the nutrients they need to grow and be healthy.

Most cow's milk formulas contain:

  • Carbohydrates, in the form of the milk sugar "lactose"
  • Iron
  • Protein
  • Minerals, such as calcium and zinc
  • Vitamins, including A, C, D, E, and the B vitamins

Some formulas add other nutrients to make them even more like breast milk, such as:

Essential fatty acids. ARA and DHA are fatty acids that are important for the baby's brain and vision.

They're naturally found in breast milk when the mother includes them in their own diet. Many formulas add them. Yet there's not a lot of evidence that formulas supplemented with fatty acids offer kids any real advantages as they grow.

Nucleotides. These building blocks of RNA and DNA are also found in breast milk and added to some formulas.

They are thought to boost the baby's immune system and help the digestive organs develop.

Prebiotics and probiotics. Probiotics are "good" bacteria that might help protect against the "bad" types of bacteria that cause infection. Prebiotics promote the growth of these good bacteria in the gut.

Formula that's supplemented with probiotics may prevent babies from getting the skin condition eczema, but it doesn't seem to help with diarrhea or colic.

Babies who were born early (before 37 weeks) or at a low birth weight (less than 5 pounds, 8 ounces) need special nutrition to help them catch up on growth. Breast-fed babies may get a fortifier added to the milk, which contains:

  • Extra calories
  • Extra fat
  • Protein
  • Vitamins
  • Minerals

Babies who can't breast-feed will need a special formula made for preterm babies. These formulas are higher in calories. They also contain extra protein, vitamins, and minerals.

One thing you don't want to give your baby during the first 12 months is whole cow's milk. It doesn't have enough iron, vitamin E, and essential fatty acids for your baby. Also, it contains too much protein, sodium, and potassium for your child's body to absorb and can cause harm. Wait to introduce cow's milk until your baby is 1 year old.

You also don't want to give your baby soy milk or homemade formula. These substitutes may not have the balance of nutrition baby needs right now.