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The purpose of this trial was to determine whether exercise without weight loss would reduce F2-isoprostanes in previously sedentary young women. Participants (N=319) were randomized to four months of 150min/week aerobic exercise or a control group. Plasma free F2-isoprostanes were measured by gas chromatography-mass spectrometry. Other assessments included fitness and % body fat. Intervention groups were compared with stratification by quartiles of baseline plasma F2-isoprostane. This stratified comparison was linearly adjusted for baseline plasma F2-isoprostane and we also used baseline plasma F2-isoprostane as a propensity score to balance the intervention. Training resulted in significant improvements in aerobic fitness (0.88 METs) and body fat percent (1%) in exercisers compared to controls (p<0.001). The exercise group had significantly higher mean baseline plasma F2-isoprostanes (79.1 vs 67.9pg/mL) than the control group in the highest quartile of baseline plasma F2-isoprostanes. Within this highest quartile, exercise led to a greater decline in plasma F2-isoprostanes (-20.2±2.5pg/mL) than control (-7.4±2.5pg/mL); with adjustment for baseline plasma F2-isoprostanes and in the balanced groups, this difference was reduced but remained significant. Four months of exercise training resulted in significant reductions of systemic oxidative stress only among previously sedentary young women who were in the highest quartile of plasma F2-isoprostanes at baseline (≥57pg/mL). Our findings indicate that the benefits of aerobic exercise in reducing systemic oxidative stress may be limited to those who present higher baseline levels of plasma F2-isoprostanes., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Phyto-oestrogens are oestrogenic compounds found in plants and consist of isoflavones, lignans and coumestans. Epidemiological studies provide evidence for a protective role of isoflavones, and to a lesser extent lignans, against the development of numerous chronic diseases, including several cancers, cardiovascular disease and osteoporosis. The structural similarity of phyto-oestrogens to endogenous oestrogens has prompted the hypothesis that phyto-oestrogens exert hormonal or anti-hormonal effects relevant to the risk of hormone-dependent disease and/or their suitability as a dietary alternative to hormone replacement therapy. The many human studies that have evaluated the effects of isoflavones and lignans on various endpoints relating to risk of various diseases have greatly increased knowledge of how these compounds behave. At the same time, additional questions have been generated. For example, the increasing interest in extracting isoflavones from the soybean for incorporation into dietary supplements has raised important concerns regarding safety and efficacy. Overall, it is clear that phyto-oestrogens are an area of active and advancing research with great potential to continue to affect human health.

Background: Soy consumption is known to reduce plasma total cholesterol and LDL cholesterol in hypercholesterolemic subjects, but the responsible soy components and the effects in normocholesterolemic subjects remain unclear., Objective: The effects of soy isoflavone consumption on plasma total cholesterol, HDL-cholesterol, LDL-cholesterol, triacylglycerol, apolipoprotein A-I, apolipoprotein B, and lipoprotein(a) concentrations and on LDL peak particle diameter were examined in normocholesterolemic, premenopausal women., Design: Thirteen healthy, normocholesterolemic, free-living, premenopausal female volunteers took part in this randomized, crossover-controlled trial. Each subject acted as her own control. Three soy isoflavone intakes (control: 10.0 +/- 1.1; low: 64.7 +/- 9.4; and high: 128.7 +/- 15.7 mg/d), provided as soy protein isolate, were consumed for 3 menstrual cycles each. Total cholesterol, HDL cholesterol, LDL cholesterol, and triacylglycerol were measured over the menstrual cycle. Apolipoprotein A-I, apolipoprotein B, lipoprotein(a), and LDL peak particle diameter were evaluated in the midluteal phase., Results: Total cholesterol, HDL-cholesterol, and LDL-cholesterol concentrations changed significantly across menstrual cycle phases (P < 0.005). During specific phases of the cycle, the high-isoflavone diet lowered LDL cholesterol by 7.6-10.0% (P < 0.05), the ratio of total cholesterol to HDL cholesterol by 10.2% (P < 0.005), and the ratio of LDL to HDL cholesterol by 13.8% (P < 0.002)., Conclusions: Isoflavones significantly improved the lipid profile across the menstrual cycle in normocholesterolemic, premenopausal women. Although of small magnitude, these effects could contribute to a lower risk of developing coronary heart disease in healthy people who consume soy over many years.

A case-control analysis of hospital-based data was conducted to evaluate whether low-dose combination oral contraceptives (OCs) protect against pelvic inflammatory disease (PID). Other categories of combination OCs based on estrogen dose were also assessed. The results indicate no OC confers protection if taken for less than 12 months. In contrast, the education-adjusted relative risk (RR) estimates for continuous exposure of greater than or equal to 12 months for various categories of combination OCs based on estrogen dose all ranged from 0.2 to 0.4 with overlapping 95% confidence intervals (CIs); however, the adjusted RR for low-dose pills was not statistically significant (RR = 0.4, 95% CI: 0.2, 1.1). These data are consistent with the hypothesis that low-dose estrogen pills as well as higher dose estrogen OCs potentially protect against PID requiring hospitalization. Low-dose estrogen combination OCs deserve further study in relation to PID generally, and more particularly, in regard to specific microorganisms causing PID.