Dietary intake of fruits and vegetables improves microvascular function in hypertensive subjects in a dose-dependent manner.

BACKGROUND: Observational evidence has consistently linked increased fruit and vegetable consumption with reduced cardiovascular morbidity; however, there is little direct trial evidence to support the concept that fruit and vegetable consumption improves vascular function. This study assessed the dose-dependent effects of a fruit and vegetable intervention on arterial health in subjects with hypertension. METHODS AND RESULTS: After a 4-week run-in period during which fruit and vegetable intake was limited to 1 portion per day, participants were randomized to consume either 1, 3, or 6 portions daily for the next 8 weeks. Endothelium-dependent and -independent arterial vasodilator responses were assessed by venous occlusion plethysmography in the brachial circulation before and after intervention. Compliance was monitored with serial contemporaneous 4-day food records and by measuring concentrations of circulating dietary biomarkers. A total of 117 volunteers completed the 12-week study. Participants in the 1-, 3-, and 6-portions/d groups reported consuming on average 1.1, 3.2, and 5.6 portions of fruit and vegetables, respectively, and serum concentrations of lutein and beta-cryptoxanthin increased across the groups in a dose-dependent manner. For each 1-portion increase in reported fruit and vegetable consumption, there was a 6.2% improvement in forearm blood flow responses to intra-arterial administration of the endothelium-dependent vasodilator acetylcholine (P=0.03). There was no association between increased fruit and vegetable consumption and vasodilator responses to sodium nitroprusside, an endothelium-independent vasodilator. CONCLUSIONS: The present study illustrates that among hypertensive volunteers, increased fruit and vegetable consumption produces significant improvements in an established marker of endothelial function and cardiovascular prognosis.

The relationship between microvascular endothelial function and carotid-radial pulse wave velocity in patients with mild hypertension.

Carotid-radial pulse wave velocity (CRPWV) can be measured rapidly using applanation tonometry and significantly higher values have been reported among patients with risk factors for vascular disease. Forearm blood flow responses to intrabrachial infusion of acetylcholine independently predict cardiovascular morbidity among hypertensive patients. We aimed to examine the relationship between CRPWV, a potentially informative, noninvasive measure and this more established parameter of arterial health. One hundred and fifteen mildly hypertensive individuals (67% men, mean (± SD) age 54 ± 8 years, mean (± SD) blood pressure (BP) 143 ± 16/83 ± 12 mmHg) were recruited from a weekly medical outpatient clinic. Each volunteer had CRPWV measured using sequential tonometry before forearm blood flow responses to intra-arterial, endothelium-dependent (acetylcholine) and independent (sodium nitroprusside) vasodilators were assessed. There was a significant negative correlation between CRPWV and maximum forearm blood flow response to acetylcholine (r = -0.225, p = 0.016). This association remained significant in a multiple regression analysis (ß = -0.213, p = 0.034). Mean arterial pressure and weight were additional independent predictors of CRPWV in this model. There was no such relationship between CRPWV and response to sodium nitroprusside (r = 0.088, p = 0.349). In patients with mild hypertension, a poor forearm blood flow response to acetylcholine independently predicted faster CRPWV, thus linking an established measure of microvascular endothelial function with a noninvasive index of conduit vessel stiffness.

Prevalence of epigastric pain, heartburn and acid regurgitation in adolescents and their parents: evidence for intergenerational association.

BACKGROUND AND AIMS: Little is known of the epidemiology of upper gastrointestinal symptoms in adolescents. We examined the prevalence of, and the risk factors for, epigastric pain, heartburn and acid regurgitation in adolescents from Northern Ireland. PARTICIPANTS: A total of 1133 adolescents aged 12-18 years participated in this study. METHODS: Questionnaires were mailed to 2017 randomly selected individuals gathering information on symptoms of epigastric pain, heartburn and acid regurgitation. Prevalences of the symptoms in the individuals and their parents were calculated. Associations between potential risk factors such as age, sex, body mass index category, smoking and frequency of symptoms were examined for both adolescents and their parents. Logistic regression was used to examine the relationship between adolescent and parental symptoms. RESULTS: Symptoms of epigastric pain, heartburn and acid regurgitation were infrequent in adolescents, but were substantially more common in parents. Adolescents were more likely to experience these symptoms if either parent experienced them, the association being much stronger if both parents were symptomatic, for example, the odds ratio (95% confidence interval) for the individual having acid regurgitation if both parents had this symptom was 6.89 (1.32, 35.7). Symptoms were more likely in adolescents who smoked and whose parents smoked, who were from lower socioeconomic backgrounds, and who had higher body mass index. For parents, smoking was positively associated with all symptoms, whereas being overweight was related to frequency of heartburn and acid regurgitation. CONCLUSIONS: Strong relationships were seen between adolescent and parental reporting of dyspeptic symptoms. Although this could be due to intrafamilial clustering of environmental factors, the associations persisted after adjusting for these. Psychosocial factors or genetic predisposition may underlie the relationships. Further research is required to explore these relationships more fully.

Fruit and vegetable consumption and bone mineral density: the Northern Ireland Young Hearts Project.

BACKGROUND: Studies examining the relation between bone mineral density (BMD) and fruit and vegetable consumption during adolescence are rare. OBJECTIVE: Our objective was to determine whether usual fruit and vegetable intakes reported by adolescents have any influence on BMD. DESIGN: BMD was measured by dual-energy X-ray absorptiometry at the nondominant forearm and dominant heel in a random sample of 12-y-old boys (n = 324), 12-y-old girls (n = 378), 15-y-old boys (n = 274), and 15-y-old girls (n = 369). Usual fruit and vegetable consumption was assessed by an interviewer-administered diet history method. Relations between BMD and fruit and vegetable intake were assessed by using regression modeling. RESULTS: Using multiple linear regression to adjust for the potential confounding influence of physical and lifestyle factors, we observed that 12-y-old girls consuming high amounts of fruit had significantly higher heel BMD (beta = 0.037; 95% CI: 0.017, 0.056) than did the moderate fruit consumers. No other associations were observed. CONCLUSION: High intakes of fruit may be important for bone health in girls. It is possible that fruit's alkaline-forming properties mediate the body's acid-base balance. However, intervention studies are required to confirm the findings of this observational study.