Inclusion Criteria:  Child age 3-17 years (up until 18th birthday) Previous diagnosis of ASD by a psychiatrist, psychologist, or developmental pediatrician Verification of diagnosis by ASU staff using the Autism Diagnostic Interview-Revised. No changes in any medical, nutritional, dietary, behavior, or other treatment in the last three months, and a willingness to avoid any changes during the study Participant is able to wear a mask during the short visit for the blood draw.  Exclusion Criteria:  Parent/guardian is unable to read or speak English fluently. Use of a vitamin/mineral supplement in the past 3 months Previous adverse reaction to a vitamin/mineral supplement Unstable, poor health; seizure disorder that is not responsive to treatment or not on stable management or complex type; or other health conditions that would significantly increase their risk of adverse effects (per physician clinical judgement) Use of any medication which has a contra-indication for one of the ingredients in the vitamin/mineral supplement A major single-gene disorder such as Fragile X, Down's Syndrome. Major brain malformation Tube feeding Current participation in other clinical trials Females who are pregnant or who are sexually active without effective birth control. Clinically significant abnormalities at baseline on two blood safety tests: Comprehensive Metabolic Panel and Complete Blood Count with Differential. Psychotropic medication use which can affect neurotransmitter levels/function - Current or within past 2 months