A Practice Note providing an overview of new dietary ingredient (NDI) notifications to the US Food and Drug Administration (FDA), as required under the Federal Food, Drug, and Cosmetic Act (FDCA), as amended by the Dietary Supplement Health and Education Act of 1994 (DSHEA). This Note covers what a "dietary ingredient" is, the difference between NDIs and old dietary ingredients (ODIs), when NDIs must be FDA-notified, and potential consequences for noncompliance with the NDI notification requirements.