My hair is getting thinner. I am a 61 year old female whose hair always been farirly thick. It is not falling out in chunks just seems thinner the last 6 weeks. I take Vit B12, Vit c, Vit D, Luetin, a mutli vitamin, and coumadin. I have taken coumadin for approx 5 years following my second episode of blood clots. I have Factor V Leiden. I am wondering if taking too many milligrams of any vitamin can cause problems.