High levels of cognitive dietary restraint (conscious limitation of food intake to achieve or maintain a desired body weight) have been associated with subclinical disturbances of the menstrual cycle and may have long-term biological implications. Therefore, it is important for future research to know if restraint scores are stable across the menstrual cycle and over time. To assess the stability of scores on the restraint subscale in relation to menstrual cycle phase, 42 women completed the Three Factor Eating Questionnaire (TFEQ) during either the early (days 1-12) or latter (days 17-36) part of their menstrual cycle. Subjects reported having regular menstrual cycles, did not use oral contraceptives and also provided self-report data on age (33.3+7.4 yr) and height and weight, from which Body Mass Index (BMI) was calculated (22.3±4.2 kg/m2). Restraint scores did not differ between women who completed the questionnaire during the early (n=25) and latter (n=17) parts of their cycle. To assess the stability of dietary restraint scores over time, 20 women who had participated in a prospective study of subclinical menstrual disturbances (Am J Clin Nutr 1994;60:887-894) completed the TFEQ at baseline and ∼18 months later. Recruitment criteria for the study included: age 20-40 yr, regular menstrual cycles, stable weight with BMI 18-25 kg/m2, nulliparous, non-smoking, exercise ≤7 hr/wk, and not using oral contraceptives. Restraint scores did not differ between baseline and follow-up, and were correlated (r=.73, P<0.001). In conclusion, these data add to information on the reliability of the TFEQ restraint subscale, and suggest that women's restraint scores are stable across the menstrual cycle and over time.