The goal of a new study published in Preventive Medicine was to understand associations between breastfeeding and health outcomes, such as child weight, up to the age of 3 years. The present analysis enrolled 3,006 women in the longitudinal, prospective First Baby Study from 2009 to 2014. Breastfeeding initiation and duration were measured using self-reported data from the 1-, 6- and 12-month surveys; child illnesses were analyzed from the 6-, 12-, and 24-month interviews; height and weight at age-3 were used to determine overweight or obese (≥85th percentile) and obese (≥95th percentile). The findings revealed that greater duration of breastfeeding was associated with fewer acute illness reports at 6 months and fewer diarrheal illness or constipation episodes at 6, 12, and 24 months. While fewer breastfed children were overweight/obese or obese at age-3, compared to non-breastfed children. Furthermore, breastfeeding duration was negatively associated with overweight/obese and obesity. The results supported the hypothesis that the duration of breastfeeding is associated with fewer reported acute illnesses at 6 months of age and diarrheal illness and/or constipation episodes at 6, 12, and 24 months. In conclusion, it was stated that breastfeeding confers a protective effect from childhood overweight/obesity since children who received breastmilk for 6 months or longer had lower chances of overweight/obesity at 3 years of age.