Musannaf Ibn Abi Shayba 33:1432

Affan narrated to us, he said: Sa'id ibn Zayd narrated to us, he said: 'Amr ibn Malik narrated to us, he said: I heard Abu al-Jawza' say: "They have no food except from *dari'* (a thorny plant)." [He said:] "How can one who eats thorns grow fat?"