Dr. Betty Choi, founder of Human Body Learning, elaborates, “Babies under 12 months should not drink juice unless a doctor recommends it for treating constipation. Babies four months and older can start trying solid or pureed fiber-rich foods. An easy way to remember fiber-rich foods is to think of the letter “p”- pears, peaches, plums, peas. Oatmeal and other vegetables can help, too.”