Is there any narration that states cucumber and dates helps to gain weight?
Yes. Imam Abu Dawud and Imam Ibn Majah (rahimahumallah) have recorded the following narration:
Sayyidatuna ‘Aaishah (radiyallahu ‘anha) says, “My mother wanted me to gain some weight before going [to the home] of Rasulullah (sallallahu ‘alayhi wa sallam). Nothing [benefitted me] until she fed me cucumber and fresh dates which [helped me] gain weight nicely.”
(Sunan Abi Dawud, Hadith: 3898, Sunan Ibn Majah, Hadith: 3324)
Imam Hakim (rahimahullah) has declared the Hadith authentic and Hafiz Dhahabi concurs.
(Mustadrak Hakim, vol. 2 pg. 185)
And Allah Ta’ala Knows best.
Answered by: Moulana Suhail Motala
Approved by: Moulana Muhammad Abasoomar
Checked by: Moulana Haroon Abasoomar