27 research outputs found
Vegetable and fruit intake and fracture-related hospitalisations: A prospective study of olderwomen
The importance of vegetable and fruit intakes for the prevention of fracture in older women is not well understood. Few studies have explored vegetable and fruit intakes separately, or the associations of specific types of vegetables and fruits with fracture hospitalisations. The objective of this study was to examine the associations of vegetable and fruit intakes, separately, and specific types of vegetables and fruits with fracture-related hospitalisations in a prospective cohort of women aged =70 years. Vegetable and fruit intakes were assessed at baseline (1998) in 1468 women using a food frequency questionnaire. The incidence of fracture-related hospitalisations over 14.5 years of follow-up was determined using the Hospital Morbidity Data Collection, linked via theWestern Australian Data Linkage System. Fractures were identified in 415 (28.3%) women, of which 158 (10.8%) were hip fractures. Higher intakes of vegetables, but not fruits, were associated with lower fracture incidence. In multivariable-adjusted models for vegetable types, cruciferous and allium vegetables were inversely associated with all fractures, with a hazard ratio (HR) (95% confidence interval) of 0.72 (0.54, 0.95) and 0.66 (0.49, 0.88), respectively, for the highest vs. lowest quartiles. Increasing vegetable intake, with an emphasis on cruciferous and allium vegetables, may prevent fractures in older postmenopausal women
Nitrate-rich vegetables do not lower blood pressure in individuals with mildly elevated blood pressure: A 4-wk randomized controlled crossover trial
Background - Emerging evidence suggests that increasing intakes of nitrate-rich vegetables may be an effective approach to reduce blood pressure.
Objective - Our primary aim was to determine whether daily consumption of nitrate-rich vegetables over 4 wk would result in lower blood pressure.
Design - Thirty participants with prehypertension or untreated grade 1 hypertension were recruited to a randomized controlled crossover trial with 4-wk treatment periods separated by 4-wk washout periods. Participants completed 3 treatments in random order: 1) increased intake (∼200 g/d) of nitrate-rich vegetables [high-nitrate (HN); ∼150 mg nitrate/d], 2) increased intake (∼200 g/d) of nitrate-poor vegetables [low-nitrate (LN); ∼22 mg nitrate/d], and 3) no increase in vegetables (control; ∼6 mg nitrate/d). Compliance was assessed with the use of food diaries and by measuring plasma nitrate and carotenoids. Nitrate metabolism was assessed with the use of plasma, salivary, and urinary nitrate and nitrite concentrations. The primary outcome was blood pressure assessed by using 24-h ambulatory, home, and clinic measurements. Secondary outcomes included measures of arterial stiffness.
Results - Plasma nitrate and nitrite concentrations increased with the HN treatment in comparison to the LN and control treatments (P \u3c 0.001). Plasma carotenoids increased with the HN and LN treatments compared with the control (P \u3c 0.01). HN treatment did not reduce systolic blood pressure [24-h ambulatory—HN: 127.4 ± 1.1 mm Hg; LN: 128.6 ± 1.1 mm Hg; control: 126.2 ± 1.1 mm Hg (P = 0.20); home—HN: 127.4 ± 0.7 mm Hg; LN: 128.7 ± 0.7 mm Hg; control: 128.3 ± 0.7 mm Hg (P = 0.36); clinic—HN: 128.4 ± 1.3 mm Hg; LN: 130.3 ± 1.3 mm Hg; control: 129.8 ± 1.3 mm Hg (P = 0.49)] or diastolic blood pressure compared with LN and control treatments (P \u3e 0.05) after adjustment for pretreatment values, treatment period, and treatment order. Similarly, no differences were observed between treatments for arterial stiffness measures (P \u3e 0.05).
Conclusion - Increased intake of nitrate-rich vegetables did not lower blood pressure in prehypertensive or untreated grade 1 hypertensive individuals when compared with increased intake of nitrate-poor vegetables and no increase in vegetables
Effects of dietary nitrate supplementation on microvascular physiology at 4559 m altitude – a randomised controlled trial (Xtreme Alps)
Native highlanders (e.g. Sherpa) demonstrate remarkable hypoxic tolerance, possibly secondary to higher levels of circulating nitric oxide (NO) and increased microcirculatory blood flow. As part of the Xtreme Alps study (a randomised placebo-controlled trial of dietary nitrate supplementation under field conditions of hypobaric hypoxia), we investigated whether dietary supplementation with nitrate could improve NO availability and microvascular blood flow in lowlanders. Plasma measurements of nitrate, nitrite and nitroso species were performed together with measurements of sublingual (sidestream dark-field camera) and forearm blood flow (venous occlusion plethysmography) in 28 healthy adult volunteers resident at 4559 m for 1 week; half receiving a beetroot-based high-nitrate supplement and half receiving an identically-tasting low nitrate 'placebo'. Dietary supplementation increased plasma nitrate concentrations 4-fold compared to the placebo group, both at sea level (SL; 19.2 vs 76.9 μM) and at day 5 (D5) of high altitude (22.9 vs 84.3 μM,
Assessment of the micronucleus assay as a biological dosimeter using cytokinesis-blocked lymphocytes from cancer patients receiving fractionated partial body-radiotherapy
Purpose: To assess the suitability of the cytokinesis block micronucleus assay as a biological dosimeter following in-vivo radiation using cancer patients undergoing radiotherapy. Methods: Blood from 4 healthy donors was irradiated in vitro with γ-rays and the dose response of induced micronuclei in binucleate lymphocytes following cytokinesis block was determined. Micronucleus frequency was ascertained before and at intervals during radiotherapy treatment in 6 patients with various tumors in the pelvic region. Equivalent whole body doses (physical doses) at these times were calculated from radiation treatment plans and cumulative dose volume histograms. Results: Linear dose response relationships were found for induced micronucleus frequency in lymphocytes resulting from both in-vitro and in-vivo irradiation. Doses resulting from in-vivo irradiation (biological doses) were estimated by substitution of micronucleus frequency observed in radiotherapy patients into the dose response curve from in-vitro irradiation of blood. The relationship between the biologically estimated dose (BD) and the calculated equivalent whole body dose (PD) was BD = 0.868(± 0.043)PD + 0.117(± 0.075). Conclusion: The micronucleus assay appears to offer a reliable and consistent method for equivalent whole body radiation dose estimation, although our findings should be confirmed using lymphocytes from radiotherapy patients with tumors at anatomical sites other than the pelvis. Except at doses lower than about 0.4 Gy, the method yields dose estimates acceptably close to 'true' physically determined doses. The assay can be performed relatively rapidly and can be used as a 'first line' biological dosimeter in situations where accidental exposure to relatively high radiation doses has occurred.Articl