When they start rolling, crawling and walking, they tend to thin out. Chubbiness in babies does not lead to obesity in adults unless overeating of fats and sugar is encouraged throughout childhood. At birth full term babies have a surplus of iron even if their mothers are anemic, but by the time they double their birth weight, they need more iron. Formulas with iron should be started by 2 months of age. Breast milk contains adequate iron.
Soy formulas contain iron also.
Cow's milk is a poor source of iron. When solids are started, iron will be obtained from enriched cereals, egg yolks, beets, beef, liver, raisins, grapes, grape juice and beet juice. Raisins and other dried fruits and sticky candy cause tooth decay so the teeth should be brushed after eating them. The soy formulas are Isomil, Prosobee and Carnation Soy. Some babies will get allergic to soy and then must try special hypoallergenic formulas, Nutramigen or Alimentum.