Does eating or drinking after the intention to fast and before the Fajr adhan affect the validity of the fast?

The intention for fasting is sufficient by the heart, and it is not legislated to utter it. It is permissible to eat and drink after intending to fast, as long as it is before the dawn becomes clear, and this is based on the Almighty's saying: "And eat and drink until the white thread of dawn becomes distinct to you from the black thread [of night]," and on the Prophet's (peace be upon him) saying: "The distinction between our fasting and the fasting of the People of the Book is the pre-dawn meal."