This is the chemical produced in the body which allows the blood vessels to relax and allow sufficient blood to flood into the penis and create an erection. If you don't get enough of it, you won't get an erection, so top it up: Gout - A type of arthritis caused by excessive uric acid in the body. This can stay in the joints (usually affecting the big toe), but can develop in any joint. It can cause severe pain, redness and swelling. Lack of sleep builds stress and lowers testosterone in your body. Lack of sleep builds stress and lowers testosterone in your body.