BACKGROUND: There are striking differences in @entity0 incidence between Asian and western @entity1 . Rates vary substantially within Asia also, with Mongolia's even lower than China's. These profound differences have been speculated to be due in part to diet, mediated by circulating hormone concentrations. METHODS: Sex @entity134 hormone concentrations were measured in @entity1 living in Ulaanbaatar, Mongolia and the United Kingdom (U.K.). Diet was obtained by interview and national survey data. Mean hormone differences were compared by country, and systematic variation by number of days since last menstrual period was modeled and adjusted for age and parity; difference in overall area under the curves was assessed. FINDINGS: The diet in Mongolia was higher in meat and dairy than in the U.K. Mean @entity251 concentrations were 18.5% lower (p<0.0001) while @entity53 concentrations were 19.1% higher (p=0.02) in Mongolian than British @entity1 , adjusted for age and parity. @entity1420 was almost 50% higher in Mongolian @entity1 (p=0.04), particularly during the follicular phase and early luteal surge. Hormone concentrations generally were similar in Mongolian @entity1 born in Ulaanbaatar compared with those born in rural areas, although there was a decreasing @entity1420 trend by degree of westernization (rural Mongolia; urban Mongolia; U.K.). Mean hormone differences were similar when restricted to parous @entity1 , and with further adjustment for body mass index, height, and smoking status. INTERPRETATION: These data augment accumulating evidence that circulating @entity172 are unlikely to explain reduced @entity0 rates in Asia compared with the west, and suggest casting a wider net with respect to biomarkers. Lower @entity251 and higher @entity1420 in Mongolian @entity1 raise the possibility that these hormones may be important to consider. In addition, the almost exclusive dietary reliance of Mongolians on meat and dairy argues against beneficial effects of a low-fat diet on circulating hormones explaining international @entity0 differences.

The Role of Hormones in the Differences in the Incidence of XXXX between Mongolia and the United Kingdom.

@entity1 :: ('9606', 'Species') :: ['women'] @entity172 :: ('MESH:D004967', 'Chemical') :: ['estrogens'] @entity251 :: ('MESH:D013739', 'Chemical') :: ['testosterone'] @entity0 :: ('MESH:D001943', 'Disease') :: ['breast cancer'] @entity1420 :: ('MESH:D011374', 'Chemical') :: ['progesterone', 'Progesterone'] @entity53 :: ('MESH:D004958', 'Chemical') :: ['estradiol'] @entity134 :: ('CHEBI:35341', 'Chemical') :: ['steroid']
@entity0 :: (MESH:D001943,Disease) :: ['Breast Cancer']
