Sex hormones in women in rural China and in Britain

Key, TJ; Chen, J.; Wang, D. Y.; Pike, Malcolm C.; Boreham, Jillian

doi:10.1038/bjc.1990.344

Cited by 183 publications

(84 citation statements)

References 37 publications

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“…This difference in levels of oestrogens has been found in both pre-and post-menopausal women. For example, British women aged 35-44, have been found to have oestradiol concentrations 36% higher on average than those of Chinese women of the same age (Key et al, 1990). Comparisons of premenopausal Western women with Asian women living in Japan (MacMahon et al, 1974;Hayward et al, 1978;Gray et al, 1982) or China (Bernstein et al, 1990), or recent migrants to Hawaii (Goldin et al, 1986), have also, in general, found lower oestrogen levels in the group of women at lower risk of breast cancer.…”

Section: Discussionmentioning

confidence: 99%

Effects of a low-fat high-carbohydrate diet on plasma sex hormones in premenopausal women: results from a randomized controlled trial

Boyd

Lockwood²,

Greenberg³

et al. 1997

Br J Cancer

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Summary We are conducting a long-term randomized controlled trial to determine if intervention with a low-fat high-carbohydrate diet reduces breast cancer risk. The present study examines the effects of 2 years of dietary intervention on serum sex hormone levels in premenopausal women. Subjects with extensive mammographic densities were enrolled in a dietary intervention trial. The intervention involved intensive individual counselling aimed at reducing total dietary fat to 15% of calories. Control subjects received general advice about diet but were not counselled to change their fat intake. Serum sex hormone levels were measured in 220 premenopausal subjects at entry and 2 years after randomization. Two years after randomization oestradiol levels were 20% (70 pmol 1-1) lower (P = 0.04) and progesterone levels were 35% (1.0 nmol 1-1) lower (P = 0.004) and follicle-stimulating hormone (FSH) levels were 7% (1 IU) higher (P = 0.38) in the intervention group than in the control group. The FSH-oestradiol ratio was 13% higher in the intervention group (P= 0.18). Samples analysed accounting for the timing of the blood sample in relation to the menstrual cycle showed that, in the intervention group, oestradiol and progesterone levels were lower and FSH levels higher in subjects with blood samples taken more than 30 days after the last menstrual period.Because of the strong evidence linking ovarian hormonal activity to breast cancer risk, these results suggest that a low-fat high-carbohydrate diet may reduce risk of breast cancer by reducing exposure to ovarian hormones that are a stimulus to cell division in the breast.

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Section: Discussionmentioning

confidence: 99%

Effects of a low-fat high-carbohydrate diet on plasma sex hormones in premenopausal women: results from a randomized controlled trial

Boyd

Lockwood²,

Greenberg³

et al. 1997

Br J Cancer

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“…Elevated serum estrogen levels and increased urinary excretion rates of estrone, estradiol, and estriol have been detected in breast cancer patients compared with controls (118). Postmenopausal women living in countries with a higher risk of breast cancer, such as the United States or United Kingdom, have elevated levels of urinary and/or serum estrogens compared with women living in countries with a lower risk of breast cancer, such as Japan, China, and Singapore (120)(121)(122)(123).…”

Section: Cancermentioning

confidence: 99%

Understanding the human health effects of chemical mixtures.

Carpenter

Arcaro

Spink

2002

Environ Health Perspect

329

198

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Most research on the effects of chemicals on biologic systems is conducted on one chemical at a time. However, in the real world people are exposed to mixtures, not single chemicals. Although various substances may have totally independent actions, in many cases two substances may act at the same site in ways that can be either additive or nonadditive. Many even more complex interactions may occur if two chemicals act at different but related targets. In the extreme case there may be synergistic effects, in which case the effects of two substances together are greater than the sum of either effect alone. In reality, most persons are exposed to many chemicals, not just one or two, and therefore the effects of a chemical mixture are extremely complex and may differ for each mixture depending on the chemical composition. This complexity is a major reason why mixtures have not been well studied. In this review we attempt to illustrate some of the principles and approaches that can be used to study effects of mixtures. By the nature of the state of the science, this discussion is more a presentation of what we do not know than of what we do know about mixtures. We approach the study of mixtures at three levels, using specific examples. First, we discuss several human diseases in relation to a variety of environmental agents believed to influence the development and progression of the disease. We present results of selected cellular and animal studies in which simple mixtures have been investigated. Finally, we discuss some of the effects of mixtures at a molecular level.

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“…In pre-and postmenopausal women, lower estrogen concentrations are generally found in Chinese compared with Caucasian women (48,49), and the ratio of the estrogen metabolites 2-hydroxyestrone to 16a-hydroxyestrone metabolites may be higher (50). Data on pregnancy estrogen concentrations, however, are not consistent with observed Asian-Caucasian differences in women who are not pregnant.…”

Section: Prominent Hypotheses To Explain Prenatal Risk Factorsmentioning

confidence: 99%

Exploring the Underlying Hormonal Mechanisms of Prenatal Risk Factors for Breast Cancer: A Review and Commentary

Troisi

Potischman

Hoover

2007

Cancer Epidemiology, Biomarkers &Amp; Prevention

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Prenatal factors have been hypothesized to influence subsequent breast cancer development. Directly evaluating the associations of in utero exposures with risk, however, presents several methodologic and theoretical challenges, including the long induction period between exposure and disease and the lack of certainty regarding the critical timing of exposure. Indirect evaluation of these associations has been achieved by use of proxies such as gestational and neonatal characteristics. Evidence suggests that preeclampsia is associated with a reduced breast cancer risk, whereas high birth weight and dizygotic twinning seem associated with an increased risk. Asians born in Asia have substantially lower breast cancer risks than women born in the West. Although data thus far are few, what exists is not consistent with a unifying hypothesis for a particular biological exposure (such as estrogens or androgens) during pregnancy as mediating the observed associations between pregnancy factors and breast cancer risk. This suggests that additional studies of prenatal factors should seek to broaden the range of hormones, growth, and other endocrine factors that are evaluated in utero. Once candidate biomarkers are identified, assessing them with respect to breast cancer and with intermediate end points in carcinogenesis should be a priority. In addition, investigations should explore the possibility that in utero exposures may not act directly on the breast, but may alter other physiologic pathways such as hormone metabolism that have their effect on risk later in life. (Cancer Epidemiol Biomarkers Prev 2007;16(9):1700 -12)

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Sex hormones in women in rural China and in Britain

Cited by 183 publications

References 37 publications

Effects of a low-fat high-carbohydrate diet on plasma sex hormones in premenopausal women: results from a randomized controlled trial

Effects of a low-fat high-carbohydrate diet on plasma sex hormones in premenopausal women: results from a randomized controlled trial

Understanding the human health effects of chemical mixtures.

Exploring the Underlying Hormonal Mechanisms of Prenatal Risk Factors for Breast Cancer: A Review and Commentary

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