Infant formula is a manufactured breast milk substitute using baby calves milk and has inferior nutrient content compared to human breast milk. Baby calves milk prioritizes the fast development of large bodies, and develops small brains. Its protein is a major cause of autism and juvenile diabetes. Human breast milk is optimal for growing larger infant brains.
By the age two, those that were breast fed had 30 percent more brain matter compared to those given formula. The extra growth was most pronounced in parts of the brain associated with language, emotional function, and cognition. The larger brains correlated to higher IQ's.
A follow up study observed that breastfeeding was positively associated with performance and intelligence at 30 years old, as with education, achievements, and higher incomes.