Final answer:
The main part of a baby's diet until they are one should be breast milk or formula. Breast milk or formula provides all the necessary nutrients for a baby's growth and development. It is recommended to exclusively breastfeed or use formula until around six months of age, and then gradually introduce solid foods while continuing to breastfeed or use formula until they are one year old.
Step-by-step explanation:
The main part of a baby's diet until they are one should be breast milk or formula.
Breast milk or formula provides all the necessary nutrients for a baby's growth and development. It contains the right balance of carbohydrates, proteins, and fats to support their rapid growth.
Introducing solid foods too early can be harmful to a baby's digestive system and increase the risk of food allergies. It is recommended to exclusively breastfeed or use formula until around six months of age, and then gradually introduce solid foods while continuing to breastfeed or use formula until they are one year old.