My daughter is 16 years old, her height is 5 feet 9 inches she weighed 144 pounds in September and now is 127 pounds. I took her to the doctor and had lab work done and everything was normal B was on the low side of normal and she isn't dehydrated. She has been what I would consider abnormally tired, poor circulation and she was a difficult blood draw. She isn't menstruating normally either and has diarrhea about 3 times a week.