Demographic, reproductive history, anthropometric, food intake, and physical activity characteristics questionnaire

The demographic questionnaire included questions about age, menopausal age, smoking, alcohol consumption, sun exposure, supplements intake, etc. In the midwifery questionnaire, questions were asked about breastfeeding history and how many pregnancies a woman has had. Weight was measured through a standard lever scale (Seca, Hamburg, Germany) with an accuracy of 0.1 kg and height by a stadiometer attached to the wall (Seca, Hamburg, Germany) with an accuracy of 0.1 cm in the required conditions.

BMI was obtained by devoted formula using weight and height. The individuals physical activity was acquired by the International Physical Activity Questionnaire (IPAQ), and the validity and reliability of it, has been reviewed and approved in Iran.[17] MET-min/week rates were obtained for light, moderate, vigorous, and total physical activity through an interview. The participants’ dietary intake was calculated for 1 week using a 24-h food diary (one holiday and two nonconsecutive workdays totally three days). Food intake was converted to grams using the guide of home scales and then analyzed in terms of dietary calcium and Vitamin D by Nutritionist IV food analysis Software (First Databank, San Bruno, CA, USA), verified according to Iranian foods.