We present findings from an integrated early childhood parenting program on stunting and wasting in Sierra Leone, West Africa. Importantly, where half the communities were randomly assigned to receive the parenting program and the remaining half served as a control that received standard nutritional counseling delivered through community meetings and home visits, keeping all social aspects of the intervention identical between the treatment and the control. We find that access to the intervention reduced the incidence of wasting by 3 percentage points and had no impact on stunting. We find improvements in parenting practices related to psychosocial stimulation and harsh discipline to be the primary mechanisms through which wasting declines. We find no differences in responsive parenting practices between the treatment and the control. These results suggest that integrated early childhood parenting programs when delivered alongside standard nutritional counseling via existing mother support groups have the potential to improve long-term well-being through reductions in wasting as well as improvements in parenting practices related to stimulation and harsh discipline.