I had ocd in my early childhood years but somehow i outgrew it but i still don't remember when i started stuttering as said by my family i started speaking very late . I never spoke till the age of 5 years which is unusual .being calm has helped me but sudden speaking situations give me a surge in my anxiety and my heart starts to pound like anything . I think magnesium glycinate would be a good supplement to calm down and reduce cortisol but i have not tried it personally.