Hello, my name is Jasper, and I'm 16. I have a friend, who suffers from advanced rates of dehydration, causing dizziness, headaches e.t.c. She does not smoke, nor is she near people who excessively smoke, rarely with smokers at all. The problem began at 13, so I'm not sure whether it is linked to puberty or not. Although, her blood is thicker than average. I was thinking, is it possible that an increased amount of oxygen carrying substances in the blood could cause this? I thought of Haemoglobin. I would like a professional's opinion on this. Thank you very much. -Jasper