Excess hair loss few years. (i'm diagnosed cfs) iron results always borderline low. also vegetarian. past 2 months, started eating iron rich cereal daily, added eggs and tuna to diet. notice decrease in hair shedding. did changing diet help this?

Very Likely: Low iron is associated with hair loss (along with inadequate protein, acute stress etc.) so so it’s quite possible that increasing your iron and protein intake is helping with your hair. It would be beneficial to recheck your iron levels and perhaps thyroid with your doctor in several months to make sure you’re on the right path- glad you’re improving!