I have to notice hair thinning myself after I hit menopause. This is the great article “Getting to the Root of Hair Loss” written by Ann Louise Gittleman ph.D. Please pay attention if you are taking one of or more from the categories of drugs she mentioned. Zinc is high in nuts and seeds and oyster if you
About supplement:
Iron and B-12 are both absorbed at the same spot in the gut that means if you have digestive issues, the chances are your Iron and B-12 markers will be low. Iron supplements are known to cause stomach pain and constipation. I recommend the food based one from Innate or Standard Process. If you are male, watch out Iron marker. I have seen ferritin (iron storage marker) is sky high in male come to see me for fatigue. The solution is frequent blood donation.
Zinc is high in nuts and seeds and oyster if you prefert to take from foods but most of zinc tablets are very small. I recommend taking once a day. Avoid Zinc Oxalate. This is the least absorble form of zinc you will see in multivitamins.