I am a 42 year old female, 5 1 and 143 pounds. For at least the last several months, my diastolic blood pressure (checked at least once a week) has been consistently between 54 and as low as 36. My systolic has been between 90 and 108, consistently. I know this is really low, is it abnormally or even dangerously low? What could be causing this? I have felt fairly normal, just really tired for the most part. I do have mild stage rheumatic heart disease, with a very, very small murmur. I also have rheumatoid arthritis, interstitial cystitis, and fibromyalgia. I am not on any medications at all, I control all my illnesses with diet and natural supplements.