A case-control study on dietary factors and colorectal adenomas was co
nducted in the island of Majorca, Spain, from April 1987 to February 1
990. Subjects were interviewed using a food frequency questionnaire. N
utrient and caloric intake was estimated using local food composition
tables. The risk of colorectal adenomas was related to the consumption
of sugar and pastries. Consumption of vegetables was highly protectiv
e, irrespective of the cooking procedures. Analyses by nutrients ident
ified as protective factors fiber from fruits and vegetables, magnesiu
m and zinc, and vitamins C, B-6 and folic acid. No excess risk was fou
nd for alcohol drinking, intake of saturated fats or animal protein. O
f the non-dietary factors, sedentariness in the workplace and urban re
sidence were the only risk factors identified. (C) 1993 Wiley-Liss. In
c.