Supporting Healthy Mothers and Infants Act of 2019 This bill modifies the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) to add requirements for supporting individuals impacted by a substance use disorder. Specifically, the bill requires the Department of Agriculture to: collaborate with the Department of Health and Human Services to develop and disseminate nutrition education materials for individuals impacted by a substance use disorder, including materials for infants impacted by prenatal substance exposure and neonatal abstinence syndrome; conduct outreach to individuals who are potentially eligible for the WIC program and who are impacted by a such a disorder; and make available to states through an online clearinghouse any nutrition education and training materials related to nutrition for individuals impacted by a substance use disorder or neonatal abstinence syndrome.