title: Levels of serum estradiol and lifestyle factors related with bone mineral density in premenopausal Mexican women: a cross-sectional analysis.
abstract: Many factors, such as heredity, ethnicity, nutrition and other lifestyle factors, have been related to bone mineral density in postmenopausal women. Additionally, bone mass has been significantly associated with decreased estrogen levels. However, fewstudies have been conducted on premenopausal women. The present study was designed to estimate the relationship between low bone mineral density and levels of serum estradiol and lifestyle factors in premenopausal Mexican women.
  
  
  
  A cross-sectional study was conducted in 270 women between 40 and 48 years of age who participate in the Health Workers Cohort Study. Information on socio-demographic and lifestyle factors were obtained through a self-administered questionnaire. Body mass index and serum estradiol were measured with standard procedures; bone mineral density was assessed using dual-energy X-ray absorptiometry. Multiple linear and logistic regression models were computed to evaluate the relationship between low bone mineral density and levels of serum estradiol and lifestyle factors.
  
  
  
  In linear regression analysis levels of estradiol, body mass index, physical activity, and vitamin D intake were positively related to bone mineral density. Age, cigarette smoking and caffeine were inversely associated with BMD. Finally, the odds of low bone mineral density increase significantly when the premenopausal women had low levels of serum estradiol (OR = 4.93, 95 % CI: 2.14, 11.37).
  
  
  
  These data support that low serum estradiol, advancing age, lower physical activity, lower vitamin D intake, cigarette smoking, and higher amount of caffeine intake are linked to low bone mineral density in premenopausal Mexican women.
authors.affiliation: Facultad de Medicina, Universidad Autónoma del Estado de México, Toluca, Estado de México, Mexico.
authors.forename: Gerardo
authors.initials: G
authors.lastname: Huitrón-Bravo
authors.affiliation: Unidad de Investigación en Epidemiología Clínica, Hospital Infantil de México "Federico Gómez", Calle Dr. Márquez No.162, Del. Cuahtemoc, Col. Doctores, C.P., 06720, Ciudad de México, Mexico. edenovag@gmail.com.
authors.forename: Edgar
authors.initials: E
authors.lastname: Denova-Gutiérrez
authors.affiliation: Unidad de Investigación Médica en Epidemiología Clínica, Hospital de Especialidades Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Ciudad de México, Mexico.
authors.forename: Juan O
authors.initials: JO
authors.lastname: Talavera
authors.affiliation: Unidad de Investigación Médica en Medicina Reproductiva, Instituto Mexicano del Seguro Social, Ciudad de México, Mexico.
authors.forename: Carlos
authors.initials: C
authors.lastname: Moran-Villota
authors.affiliation: Comité Mexicano para la prevención de la Osteoporosis, Ciudad de México, Mexico.
authors.forename: Juan
authors.initials: J
authors.lastname: Tamayo
authors.affiliation: Área Académica de Nutrición, Universidad Autónoma del Estado de Hidalgo, Pachuca, Hidalgo, Mexico.
authors.forename: Arianna
authors.initials: A
authors.lastname: Omaña-Covarrubias
authors.affiliation: Unidad de Investigación Epidemiológica y en Servicios de Salud, Instituto Mexicano del Seguro Social, Morelos, Mexico.|Centro de Investigación en Salud Poblacional, Instituto Nacional de Salud Pública, Cuernavaca, Morelos, Mexico.
authors.forename: Jorge
authors.initials: J
authors.lastname: Salmerón
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D000367:Age Factors; D015992:Body Mass Index; D015519:Bone Density; D002110:Caffeine / Q000009:adverse effects; D002136:Calcium, Dietary / Q000008:administration & dosage; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D019587:Dietary Supplements; D004958:Estradiol / Q000097:blood*; D015444:Exercise; D005260:Female; D006801:Humans; D008019:Life Style; D008800:Mexico; D008875:Middle Aged; D010024:Osteoporosis / Q000097:blood*; D017697:Premenopause / Q000097:blood*; D012907:Smoking / Q000009:adverse effects; D011795:Surveys and Questionnaires; D014807:Vitamin D / Q000008:administration & dosage
chemical_list: D002136:Calcium, Dietary; D014807:Vitamin D; D002110:Caffeine; D004958:Estradiol
keywords: Bone mineral density; Mexican women; Premenopausal; Serum estradiol