Nicotinamide crystals, coloured scanning electron micrograph (SEM). Nicotinamide is a water-soluble form of vitamin B3 or niacin. It is made in the body by eating niacin-rich foods such as fish, poultry, nuts, legumes, eggs, and cereal grains. Nicotinamide supplements are used to treat skin conditions and niacin deficiencies. Recent studies suggest nicotinamide may protect against some forms of skin lesions in patients with sun-damaged skin. Additional studies are needed to confirm safety and effectiveness across different types of skin cancer and in different people. In addition, the protective effects of nicotinamide against UV exposure does not mean that it protects against sunburn. Magnification: x1500 when printed 10 centimetres wide.