Publications by authors named "Aina Emaus"

Objective: Although physical activity modulates the hypothalamic-pituitary-ovarian axis, the few studies that have investigated whether physical activity is associated with age at natural menopause have yielded mixed results. We set out to determine whether physical activity is associated with the timing of natural menopause in a large cohort of California women overall and by smoking history.

Methods: We investigated the association between long-term physical activity (h/wk/y) and age at natural menopause among 97,945 women in the California Teachers Study.

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Objective: There is conflicting evidence as to whether duration of lactation may decrease the risk of subsequent development of an unfavorable maternal metabolic profile, including overweight and obesity. We hypothesized that duration of lactation is associated with a more favorable metabolic profile and healthier anthropometric measurements.

Subjects And Methods: Ninety-eight parous women were studied from the Norwegian EBBAI-study (Energy Balance and Breast cancer Aspects-study), a cross-sectional study of healthy premenopausal women 25-35 years old.

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Since lung cancer is among the cancers with the highest incidence and has the highest mortality rate of cancer worldwide, the means of reducing its impact are urgently needed. Emerging evidence shows that physical activity plays an etiological role in lung cancer risk reduction. The majority of studies support the fact that total and recreational physical activity reduces lung cancer risk by 20-30% for women and 20-50% for men, and there is evidence of a dose-response effect.

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Aims: To study the association between self-reported physical activity (PA) and objectively measured PA, resting heart rate, and physical fitness.

Methods: During 2007-08, 5017 men and 5607 women aged 30-69 years attended the sixth survey of the Tromsø study. Self-reported PA during leisure-time and work were assessed and resting heart rate was measured.

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Metabolic components [body mass index (BMI), blood pressure, serum lipids] and physical activity may affect biological mechanisms of importance for breast cancer prognosis. A population-based survival study among 1,364 breast cancer cases within the Norwegian Counties Study during 1974-2005 was conducted. Pre-diagnostic measurements of BMI, blood pressure, serum lipids, and self-reported physical activity were assessed.

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Background: Adult height and insulin are thought to modify the development of breast cancer. However, little is known about the association between height and 17beta-estradiol, a key factor in breast carcinogenesis, and whether insulin modifies such an association.

Methods: Among 204 healthy women, ages 25 to 35 years, who participated in the Energy Balance and Breast Cancer Aspect I study, adult height (in centimeters) and fasting serum concentrations of insulin (pmol/L) were measured.

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Background: Estrogens induce cellular proliferation and are associated with an increased risk of breast cancer. Birth weight and adult body weight have independently been associated with both estrogen levels and breast cancer risk. Thus, we hypothesize that low birth weight, in combination with adult overweight, may influence premenopausal 17beta-estradiol over an entire menstrual cycle of possible importance for breast cancer.

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Purpose: To study whether physical inactive women with a tendency to develop metabolic syndrome have high levels of 17beta-estradiol (E2) of importance for breast cancer risk.

Methods: Two hundred and four healthy women of reproductive age were assessed for self-reported leisure-time physical activity (LPA), resting heart rate (HR), blood pressure (BP), anthropometry, and serum glucose, lipids, and insulin [Norwegian Energy Balance and Breast Cancer Aspect (EBBA) study]. E2 was measured in daily saliva samples throughout an entire menstrual cycle.

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Increasing bodyweight among women worldwide seems to be associated with a proportional rise in the number of women developing breast cancer. It is of utmost importance to obtain reliable biomarkers that may help clinicians to identify susceptible individuals among the growing population of women with excess adiposity. Our recent studies, reviewed within this article, support that adiposity-related metabolic disorders may represent high-risk phenotypes; specifically, we conclude that a low level of high-density lipoprotein cholesterol may be a reliable marker for breast cancer risk among overweight women.

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Low serum high-density lipoprotein cholesterol (HDL-C) is an important component of the metabolic syndrome and has recently been related to increased breast cancer risk in overweight and obese women. We therefore questioned whether serum HDL-C might be a biologically sound marker of breast cancer risk. We obtained cross-sectional data among 206 healthy women ages 25 to 35 years who participated in the Norwegian EBBA study.

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