Compiled by Imam Yahya ibn Sharaf al-Nawawi
وعن أبي كريمة المقدام بن معديكرب رضي الله عنه قال: سمعت رسول الله صلى الله عليه وسلم يقول “ما ملأ آدمي وعاء شراً من بطن، بحسب ابن آدم أكلات يقمن صلبه، فإن كان لا محالة؛ فتلث لطعامه وثلث لشرابه، وثلث لنفسه". ((رواه الترمذي وقال: حديث حسن)). "أكلات" أي: لقم.
I heard Messenger of Allah (ﷺ) say: "No man fills a container worse than his stomach. A few morsels that keep his back upright are sufficient for him. If he has to, then he should keep one-third for food, one-third for drink and one-third for his breathing."[At-Tirmidhi, who classified it as Hadith Hasan].