Type B insulin resistance is a rare disorder that affects middle-aged adults. This occurs when a person's body no longer responds appropriately to insulin. Insulin is a messenger that tells the body to break down sugars to make energy needed for daily life. For people with type B insulin resistance, however, their body cannot convert sugar to energy the same way most people’s does. Symptoms of type B insulin resistance include sudden development of severe diabetes, dark, velvety skin around the armpits or neck, and excessive hair growth. People with type B insulin resistance typically require insulin injections to manage their blood-sugar levels, although this is not always effective. Talk with your doctor to find the best treatment for you if you have been diagnosed with type B insulin resistance.