The following is abstracted from "Malfuzat e Attarriyya" (Utterances of Mohammed Ilyas Attar Qadri).
Someone asked the sheikh: Vegetables are usually a part of your diet. What is the wisdom behind it?
Sheikh replied: Praise be to Allah, vegetables have cure for several ailments [diseases]. Sayiduna Jabir bin Abdullah (may Allah be pleased with them) has narrated that vinegar is the best gravy [curry], and Prophet (Sallallaho Alihi Wassallam), use to like vegetables. It is narrated in "Kanzul Ubaad" that the angles visit the tablecloth which has vegetables on it.
Prophet of Allah (Sallallaho Alihi Wassallam) loved gourd [squash]. In a narration by "Abu Naeem" Prophet of Allah (Sallallaho Alihi Wassallam) said "Oh people! Eat plenty of squash because it strengthens the brain. In another narration, Prophet (Sallallaho Alihi Wassallam) said, "Oh Ayesha! Whenever you cook add few pieces of squash because it strengthens the depressed heart". One should make a habit of putting a few pieces of squash while cooking the meat so that one gets the reward of following a sunnah and also get other benefits narrated above. Sayiduna Zahbbi (may Allah's mercy be upon him) narrates in "Tibb e Nabwi" [Medicine of the Prophet Sallallaho Alihi Wassallam] eating squash increases the brain [capabilities]. Prophet (Sallallaho Alihi Wassallam) said that squash cleans the chest and strengthens the heart.
It is narrated in Bukhari & Muslim etc. that Sayiduna Anus (may Allah be pleased with him) narrates that, one tailor invited the Prophet (Sallallaho Alihi Wassallam) and presented barley bread and stew with squash and dried meat. I saw Prophet Sallallaho Alihi Wassallam finding pieces of squash from the bowl [serving dish] and eating it. After that day I loved [to eat] squash!.
Someone asked the sheikh: Olives are often seen on your tablecloth and you prevent us from throwing its seed! What is the reason behind it?
Sheikh replied: I eat olives as a 'tabaruk' [blessing]. (Narrating the benefits of olives he said,) olive tree is a blessed tree. It is said in the Holy Quran: (AlNoor 24:35) "from the blessed olive tree." It is in "Tafseer e Sawwi" 70 Prophets Allhimus Salam made benediction [dua'] for its blessing including Prophet Abraham Allihis Salam and above all, the Master of Prophets, Our Prophet Sallallaho Alihi Wassallam.
I do not throw the seed away out of respect and to respect the olive seed is by the guidance of the conscious. (He further narrated) After the storm of Noah Allihis Salam, the first tree that grew was that of an olive. And first time the Olive tree grew [in this world] was on the Mount of Turr where Prophet Moses, Allihis Salam talked with Allah Almighty.
The life of an olive tree is very long some scholars say it lives for 3,000 years. It is narrated in "Khazayin ul Irfan" [tafseer of Quran] that its leaves do not shed. Its oil is called "Zi'et", and any oil in this world does not match the qualities of the olive oil. (He further said) it is in a narration from "Abu Naeem" The master of medicine, the doctor of doctors, Allah's Prophet Sallallaho Alihi Wassallam said, eat olives and use its oil for it has cure for 70 diseases and one of them is leprosy. Eating 25 grams of olive oil daily will cure old [chronic] constipation. Olive pickles increase appetite and relieve constipation.
Someone asked the sheikh: It is often seen that you drink water before your meals, any wisdom behind it?
Sheikh replied: I have read a quote of Sayiduna Luqman, may Allah be pleased with him, that to drink water before a meal is health, during a meal is medicine and after a meal is burden. Allah and Allah's Prophet Sallallaho Alihi Wassallam know (he further said) Physicians also agree. According to medicine it is beneficial to drink water before eating fruits. By principle fruits should be eaten before the meal but today fruits are generally eaten after the meal. It is also beneficial to drink water before tea [or coffee].