It is good you have been checked by a doctor. I do not know what hypothyroidism is, but is sure sounds like something to do with the thyroid.. yet: "they say my thyroid was good." I assume "they" are/is a doctor.
Watch out for weight gain if you eat much chocolate, it sure sticks to my bones, I have to avoid it, then I have a problem with a too high HR anyway.
Shortness of breath could be related to a lack of blood oxygen due to the low HR...I don't know of any connection between heart rhythm and brittle nails. That said, I have some finger nail problems myself. I'm not sure they are brittle, but they do crack right at the ends. I have to keep the nails cut real short or I'll break them when I snag one on something. My nails look "normal" otherwise to my mind.
to answer questions, my symptoms are shortness of breath sometime, brittle nails, dry hair, symptoms that are related to hypothyroidism....they said my thyroid was good.
Thanks for the information Jerry...I do drink coffee and have indeed found that it increase my HR.....I think coffee, chocolate, and tea sounds good to me.
What symptoms result from your 40s (resting?) heart rate? If you have none, that is you are able to lead a "normal" active life then I'd say nothing needs to be done. If you also have low blood pressure and find you are dizzy or worse, then a higher HR is needed.
To my understanding many people with healthy hearts live with a resting HR in the 40s and do fine. Does caffeine make you HR go higher? Many (most?) people consume some caffeine (coffee, tea, chocolate) each day and if you don't you may fine some of that in moderation may elevate your HR. Just and idea. Maybe just a test. I don't react strongly to caffeine or the lack of, but know if I drink several cups of coffee in a morning period I get very nervous and over stimulated. I have not drank that much regular coffee in years...but that's what I recall.