Supporting Healthy Mothers and Infants Act of 20 21 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 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.