Using a form of B-12 called Cyanocobalamin, a synthetic form the vitamin, B-12 injections are administered into the muscles under the skin. By stimulating the production of new blood cells, B-12 injections are widely used to improve the health of hair, skin and nails. Injections can improve the appearance of wrinkles and repair the skin, preventing the signs of aging. B-12 injections can also boost your metabolism and improve your energy levels! They can not only increase your metabolism but also give you more energy for exercise, helping you meet your weight loss goals.