Just a quick passage tonight, it’s been a long day
Onions are hot in the fourth degree and moist in the third and cause unchastity and headaches. To those who eat them raw they cause bad moisture and bring great thirst to people.
Garlic is hot and dry in the middle of the fourth degree and has the properties of onions, and in addition it drives out winds and pressure (das bleen) in the body. Its damage, when it is eaten, is that it brings great heat and bad moisture and its vapors rise up into the head. But garlic does less harm in cold countries and cold seasons than in the summer, or in hot countries, according to Master Rhazes.
I admit I did not know this about onions and will make a point of inviting my comely lady friends for some onion soup in future.
Joking aside, this is very much the standard view of onions and garlic. They were regarded as common, low-status foods that had no place at the lordly table, though there is also good evidence they were relished by many. Bock also views them as an effective antidote to poor-quality, illness-inducing water:
But in summer our peasants, when hay is made and grain harvested, drink all manner of water as they can get it, and they eat much onions and garlic upon it. Thus the raw, evil water is distilled and digested and what is evil in it departs from them with great steam and foul smell. Thus they rarely suffer harm from drinking water, for which they should thank the egyptian gods, onions and garlic.
(p. xv v)
Meister Eberhard is a recipe collection that belongs into a south German context, most likely associated with the court of Bayern-Landshut during its ascendancy in the first half of the 15th century. We know nothing about the putative author other than that he claims he was part of the kitchen staff there. The text contains an eclectic mix of recipes and dietetic advice heavily cribbed from a variety of sources, including the (unattributed) writings of St Hildegardis Bingensis. The text is published in A. Feyl: Das Kochbuch Meister Eberhards. Diss. Freiburg i.B. 1963 and online on the website of Thomas Gloning.