There is a fabricated report which claims that the Prophet said, “Ali, begin and conclude your meal with salt, since salt is a cure for seventy illnesses such as insanity, leprosy, stomach pain and tooth ache.” Scholars of hadith declared this report to be baseless. So there is no recommendation in Islam to eat salt.
What the Qur’an and Sunnah Say
Ali said, “Whosoever commences his meal with salt, Allah will eliminate seventy types of illnesses from him.” (Bayhaqi, Shu`ab Al-Iman)
The Messenger of Allah said, “The best of your seasonings is salt.” (Ibn Majah #3315) This report has been graded weak by scholars.
What the Scholars Said
Imam Ibn Abidin says, “It is from the sunnah (way of the Prophet) to commence and conclude one’s meals with salt, in doing so there is cure from seventy illnesses.” (Radd al-Muhtar 6:340) Some similar is stated in Al-Muhit al-Burhani 5:204, Al-Bahr ar-Ra’iq 8:209, Al-Fatawa al-Hindiyya 5:337, and Ihya Uloom ad-Din).
Despite these weak reports and what some scholars said, this recommendation is not based on an authentic practice that was done by the Messenger of Allah, so you should not believe it is part of Islamic practice.
Shaykh Mustafa Umar