Passage: She developed the Budwig protocol, a purported anti-cancer diet, in 1952. The basis of the diet is modifying dietary fats. It is rich in flaxseed oil, mixed with cottage cheese and meals high in fruits, vegetables, and fiber and avoids sugar, animal fats, salad oil, meats, butter, and especially margarine.

Question: What kind of oil is rich in a 1952 proposed anti-cancer diet?
flaxseed