Babies who are breast-fed for their first four months of life have a reduced risk of asthma during their first four years, says a Swedish study in the October issue of the Journal of Allergy and Clinical Immunology.Researchers analyzed data about 4,089 infants and found an asthma rate of 6.4 percent among 4-year-old children who’d been exclusively breast-fed for the first four months or longer, compared with 9.1 percent of those who’d been exclusively breast-fed for less than four months.