5mg of folic acid (daily) safe to use? will it help in growing hair faster and thicker?

listen to your body: Folic acid is generally considered safe but this is not a dose to correct deficiencies. Some individuals find high doses of Folic Acid cause them to feel hyperactive and excitable. If hair isn't growing normally you may be under stress. Avoid alcohol, tobacco, and junk food. Eat healthy, get a good night sleep, reduce stress, and exercise to foster health.