High blood glucose levels can damage the body’s nerves, weakening their ability to transmit signals. Raised blood glucose can also harm the blood vessels that carry oxygen and nutrients to the nerves. Sensory neuropathy affects the nerves that carry messages from the skin, bones and muscles to the brain. It mainly occurs in the legs and feet but can also occur in the arms and hands. Symptoms include numbness, tingling and extreme sensitivity to touch. Automatic neuropathy affects the nerves that control the automatic workings of the body. These include the sexual organs, stomach, intestine, sweat glands and sometimes the heart. Motor neuropathy is rare and affects the eyes and muscles of the legs and feet. It causes muscle weakness and in certain areas muscle wasting can occur. If the nerves that supply the muscles in the foot are affected it can lead to the development of foot deformities.