Niacinamide is an ingredient found in some toothpaste products. It is used to strengthen tooth enamel, repair oral damage, and reduce tooth sensitivity

. Niacinamide is also known to have benefits for the skin, such as reducing inflammation and improving the appearance of fine lines and wrinkles

. Some toothpaste products with niacinamide claim to whiten teeth, remove stains, and freshen breath

. However, there is insufficient evidence to support the effectiveness of niacinamide for these purposes

. When taken by mouth, niacinamide is generally safe for most adults, but may cause minor side effects such as stomach upset, intestinal gas, dizziness, rash, and itching

. When applied topically, niacinamide cream may cause mild burning, itching, or redness

. It is important to consult with a healthcare provider before supplementing with niacinamide or using products containing this ingredient.