“Plato’s works are imbued with the fundamental principle of moderation. This spirit is characteristically evident in his references to human diet. According to the philosopher, a moderate and thus a healthy diet, consists of cereals, legumes, fruits, milk, honey and fish. However, meat, confectionery and wine should be consumed only in moderate quantities. Excesses in food lead to ailments and therefore should be avoided.”

from: Skiadas PK and Lascaratos JG: Dietetics in ancient Greek philosophy: Plato’s concepts of healthy diet. Eur J Clin Nutr. 2001 Jul;55(7):532-7. (full text)