Al-Kāfi - Volume 6 > The Lettuce
Hadith #1

عِدَّةٌ مِنْ أَصْحَابِنَا عَنْ أَحْمَدَ بْنِ أَبِي عَبْدِ اللَّهِ عَنْ أَبِيهِ عَنْ بَعْضِ أَصْحَابِهِ عَنْ أَبِي حَفْصٍ الْأَبَّارِ عَنْ أَبِي عَبْدِ اللَّهِ ( عليه السلام ) قَالَ عَلَيْكُمْ بِالْخَسِّ فَإِنَّهُ يُصَفِّي الدَّمَ .

1. A number of our people have narrated from Ahmad ibn abu ‘ Abd Allah from his father from certain persons of his people from abu Hafs ibn al-Abbar who has said the following: “Abu ‘Abd Allah, ‘Alayhi al-Salam, has said, ‘You must eat lettuce because it cleanses blood.’”