Objective: To evaluate the relations of intakes of soy, fat and other dietary components to premenstrual symptoms.
Design: Cross sectional study.
Setting: Three colleges and two nursing schools.
Population: One hundred and eighty-nine Japanese women aged 19 to 34 years.
Methods: Intakes of nutrients and foods, including soy products and isoflavones, were estimated by a semiquantitative food frequency questionnaire. Change in menstrual cycle symptoms were assessed by the Moos Menstrual Distress Questionnaire (MDQ).
Main outcome measures: Spearman rank correlation of soy and other dietary factors with changes in MDQ scores between the follicular and the premenstrual phases after controlling for age, marital status, exercise, smoking status, age at menarche and number of days of bleeding.
Results: Neither soy product nor isoflavone intake was significantly associated with change in MDQ score in the premenstrual phase. Intakes of total, saturated and monounsaturated fats were significantly correlated with change in scores for total MDQ and subscale 'pain' in the premenstrual phase after controlling for the covariates. Intake of cereals/potatoes/starches was significantly inversely correlated with a change in total MDQ score in the premenstrual phase.
Conclusions: High intake of fats and low intake of foods with high concentration of carbohydrate may be associated with premenstrual symptoms.