:salamext:
Yep, you eat something before fajr it can be anything but the Prophet (sallahu alayhi wasallam) did eat dates.
The Messenger (S) said:"The best Suhoor for the believer is dates." [Abu Dawood, Al-Baihaqee and Ibn Hibbaan]
There is also a lot of blessings in suhoor (pre dawn meal) so it is highly recommended that you do it.
Salmaan (R) said that the Messenger of Allah (S) said: "Blessings are found in three things, the Group (Al-Jama'ah), Ath-thareed (a type of food) and As-Sahoor (the Pre-dawn meal)."[At-Tabaraanee, Abu Na'eem]
Abu Hurairah (R) said that the Messenger (S) of Allah (T) said: "Verily Allah placed Barakah (blessing) in the Sahoor (pre-dawn meal) and in perfect measurement (weighing)."[Ash-Shairazee]
Abdullah Ibn Haarith said that one of the Sahabah (companion) said: 'I entered the house of the Messenger (S) whilst he was taking the Sahoor (pre-dawn meal), and he (S) said: "Indeed it (the Sahoor) is blessing that Allah has given to you so do not leave it out." [An-Nasaaee and Ahmad]
Abu Sa'eed al-Khudree said that the Messenger (S) said: "Eating the Sahoor is blessed. Do not neglect it even if you take a gulp of water, because Allah and His angels invoke blessings upon those who partake in the pre-dawn meal." [Ahmad]