Hawzah News Agency – The merciful prophet of Islam, peace be upon him and his household says:

مَنْ قَلَّ طُعْمُهُ صَحَّ بَطْنُهُ وَصَفَا قَلْبُهُ، وَمَنْ كَثُرَ طُعْمُهُ سَقُمَ بَطْنُهُ وقَسَا قَلْبُهُ.

'A man whose [consumption of] food is little has a healthy stomach and a pure heart, and a man whose food is plenty has a sick stomach and a hard heart.'

Source: Tanbih al-Khawatir, v. 1, p. 46