زيت الزيتون
Oil from the olive, described as coming from a 'blessed tree,' recommended both as food and rubbed onto the skin.
كُلُوا الزَّيْتَ وَادَّهِنُوا بِهِ، فَإِنَّهُ مِنْ شَجَرَةٍ مُبَارَكَةٍ
“Eat olive oil and rub it on your skin, for it comes from a blessed tree.” (meaning, not a literal translation)
The description "blessed tree" (shajaratin mubarakatin) echoes language used for the olive in the Qur'an itself (Surah An-Nur 24:35), where it appears in a well-known verse describing light. The hadith is unusual among Prophetic-medicine reports in explicitly recommending both internal (eating) and external (topical) use in the same single statement.
Ibn al-Qayyim notes olive oil as warming and softening, beneficial for joints and skin when massaged in, and slow to spoil compared to other oils of the era. He describes it as suited to easing joint stiffness when warmed and applied externally, and, taken internally, as gently supportive of digestion without the heaviness of some other fats used in the classical diet.
Olive oil, particularly extra-virgin, is one of the more extensively studied dietary fats in modern nutrition, with substantial research linking it to cardiovascular benefits as a core component of the Mediterranean diet pattern. Noted here as separate modern nutritional context, not as a direct validation of the specific topical benefit described in the hadith.