Nutrient intake and blood pressure in the Dietary Intervention Study in Children

Dietary protein and blood pressure: an umbrella review of systematic reviews and evaluation of the evidence

INTRODUCTION

This umbrella review aimed to investigate the evidence of an effect of dietary intake of total protein, animal and plant protein on blood pressure (BP), and hypertension (PROSPERO: CRD42018082395).

METHODS

PubMed, Embase and Cochrane Database were systematically searched for systematic reviews (SRs) of prospective studies with or without meta-analysis published between 05/2007 and 10/2022. The methodological quality and outcome-specific certainty of evidence were assessed by the AMSTAR 2 and NutriGrade tools, followed by an assessment of the overall certainty of evidence. SRs investigating specific protein sources are described in this review, but not included in the assessment of the overall certainty of evidence.

RESULTS

Sixteen SRs were considered eligible for the umbrella review. Ten of the SRs investigated total protein intake, six animal protein, six plant protein and four animal vs. plant protein. The majority of the SRs reported no associations or effects of total, animal and plant protein on BP (all "possible" evidence), whereby the uncertainty regarding the effects on BP was particularly high for plant protein. Two SRs addressing milk-derived protein showed a reduction in BP; in contrast, SRs investigating soy protein found no effect on BP. The outcome-specific certainty of evidence of the SRs was mostly rated as low.

DISCUSSION/CONCLUSION

This umbrella review showed uncertainties whether there are any effects on BP from the intake of total protein, or animal or plant proteins, specifically. Based on data from two SRs with milk protein, it cannot be excluded that certain types of protein could favourably influence BP.

Association of the Protective Dietary Pattern for Blood Pressure with Elevated Blood Pressure and Hypertension among Chinese Children and Adolescents Aged 6-17 Years Old: Data from China Nutrition and Health Surveillance (2015-2017)

Studies focused on the association between dietary patterns and elevated blood pressure (BP) and hypertension (HTN) among children and adolescents remain insufficient. This study aimed to explore a dietary pattern that could be helpful for the prevention of abnormal BP and to investigate the association between this dietary pattern and elevated BP and HTN among Chinese children and adolescents. A total of 52,080 Chinese children and adolescents aged 6~17 years old from the China Nutrition and Health Surveillance (CNHS) 2015-2017 were included in the current study. The reduced rank regression (RRR) method was applied to derive a dietary pattern that is associated with BP. Multivariable logistic regression was used to assess the association between dietary pattern (DP) and elevated BP and HTN. The Dietary Approach to Stop Hypertension (DASH) score was also calculated for each participant as a comparative method to validate the dietary pattern derived with the RRR method. A protective dietary pattern (PDP) for BP among Chinese children and adolescents was derived, which was characterized by high intakes of dairy products, mushrooms/edible fungi, fresh vegetables, fresh fruits, fresh eggs, aquatic products, mixed legumes, soybeans and related products, offal, dried fruits, and coarse cereals, with low intakes of refined grains. After multiple adjustments, there were significant inverse associations between PDP scores and the odds of elevated BP and HTN (elevated BP: Q5 vs. Q1, OR = 0.849, 95%CI = 0.755-0.931, P-trend < 0.05; HTN: Q5 vs. Q1, OR = 0.795, 95%CI = 0.694-0.911, P-trend < 0.05). The DASH diet was also observed to have protective effects on elevated BP in model I (Q5 vs. Q1, OR = 0.899, 95%CI = 0.828-0.975, P-trend < 0.05), but was not observed to have protective effects on HTN (HTN: Q5 vs. Q1, OR = 0.958, 95%CI = 0.876-1.048, P-trend > 0.05). The current study suggested that greater adherence to the PDP for BP among Chinese children and adolescents might be associated with lower odds of elevated BP and HTN.

Association of dietary fatty acid intake with hypertension in children and adolescents: evidence from the NHANES 2005-2018

Aim

This study aims to evaluate the association between dietary fatty acid intake and hypertension in children and adolescents.

Methods

This cross-sectional study used data of children and adolescents aged 8-17 years from the National Health and Nutrition Examination Survey (NHANES) 2005-2018. Dietary intake of total fat and fatty acid was evaluated via two 24-h dietary recall interviews. Multivariate logistic regression models were used to assess the association between fatty acid intake and hypertension, with odds ratios (ORs) and 95% confidence intervals (CIs) calculated. A subgroup analysis was conducted according to gender, age, and body mass index Z-score.

Results

This study included 13,330 subjects, of which 11,614 were non-hypertensive and 1,716 were hypertensive. Higher intake of total polyunsaturated fatty acids (PUFAs) was associated with significantly lower odds of hypertension (OR = 0.85, 95% CI: 0.74-0.97, P = 0.018). No significant associations were found between the density of total saturated fatty acid, monounsaturated fatty acids, and PUFAs and the odds of hypertension (all P > 0.05). Increased intake of omega-3 (OR = 0.82, 95% CI: 0.72-0.93, P = 0.002) and omega-6 (OR = 0.86, 95% CI: 0.75-0.98, P = 0.025) PUFAs, octadecatrienoic acid (OR = 0.82, 95% CI: 0.72-0.93, P = 0.003), and octadecadienoic acid (OR = 0.86, 95% CI: 0.75-0.98, P = 0.025) was associated with significantly lower odds of hypertension, and individuals with higher omega-6/omega-3 ratio had significantly higher odds of hypertension (OR = 1.09, 95% CI: 1.02-1.17, P = 0.025). The density of omega-3 PUFAs (OR = 0.86, 95% CI: 0.78-0.95, P = 0.004) and octadecatrienoic acid (OR = 0.87, 95% CI: 0.78-0.96, P = 0.006) was inversely associated with the odds of hypertension, and the omega-6/omega-3 ratio was positively associated with the odds of hypertension (OR = 1.09, 95% CI: 1.02-1.17, P = 0.012).

Conclusion

Total PUFA intake was negatively associated with the odds of hypertension in children and adolescents. Higher intake of omega-3 and omega-6 PUFAs, octadecatrienoic acid, and octadecadienoic acid, as well as density of omega-3 PUFAs and octadecatrienoic acid, was associated with lower odds of hypertension.

Effects of total fat intake on bodyweight in children

BACKGROUND

As part of efforts to prevent childhood overweight and obesity, we need to understand the relationship between total fat intake and body fatness in generally healthy children.

OBJECTIVES

To assess the effects and associations of total fat intake on measures of weight and body fatness in children and young people not aiming to lose weight.

SEARCH METHODS

For this update we revised the previous search strategy and ran it over all years in the Cochrane Library, MEDLINE (Ovid), MEDLINE (PubMed), and Embase (Ovid) (current to 23 May 2017). No language and publication status limits were applied. We searched the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov for ongoing and unpublished studies (5 June 2017).

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in children aged 24 months to 18 years, with or without risk factors for cardiovascular disease, randomised to a lower fat (30% or less of total energy (TE)) versus usual or moderate-fat diet (greater than 30%TE), without the intention to reduce weight, and assessed a measure of weight or body fatness after at least six months. We included prospective cohort studies if they related baseline total fat intake to weight or body fatness at least 12 months later.

DATA COLLECTION AND ANALYSIS

We extracted data on participants, interventions or exposures, controls and outcomes, and trial or cohort quality characteristics, as well as data on potential effect modifiers, and assessed risk of bias for all included studies. We extracted body weight and blood lipid levels outcomes at six months, six to 12 months, one to two years, two to five years and more than five years for RCTs; and for cohort studies, at baseline to one year, one to two years, two to five years, five to 10 years and more than 10 years. We planned to perform random-effects meta-analyses with relevant subgrouping, and sensitivity and funnel plot analyses where data allowed.

MAIN RESULTS

We included 24 studies comprising three parallel-group RCTs (n = 1054 randomised) and 21 prospective analytical cohort studies (about 25,059 children completed). Twenty-three studies were conducted in high-income countries. No meta-analyses were possible, since only one RCT reported the same outcome at each time point range for all outcomes, and cohort studies were too heterogeneous to combine.Effects of dietary counselling to reduce total fat intake from RCTsTwo studies recruited children aged between 4 and 11 years and a third recruited children aged 12 to 13 years. Interventions were combinations of individual and group counselling, and education sessions in clinics, schools and homes, delivered by dieticians, nutritionists, behaviourists or trained, supervised teachers. Concerns about imprecision and poor reporting limited our confidence in our findings. In addition, the inclusion of hypercholesteraemic children in two trials raised concerns about applicability.One study of dietary counselling to lower total fat intake found that the intervention may make little or no difference to weight compared with usual diet at 12 months (mean difference (MD) -0.50 kg, 95% confidence interval (CI) -1.78 to 0.78; n = 620; low-quality evidence) and at three years (MD -0.60 kg, 95% CI -2.39 to 1.19; n = 612; low-quality evidence). Education delivered as a classroom curriculum probably decreased BMI in children at 17 months (MD -1.5 kg/m2, 95% CI -2.45 to -0.55; 1 RCT; n = 191; moderate-quality evidence). The effects were smaller at longer term follow-up (five years: MD 0 kg/m2, 95% CI -0.63 to 0.63; n = 541; seven years; MD -0.10 kg/m2, 95% CI -0.75 to 0.55; n = 576; low-quality evidence).Dietary counselling probably slightly reduced total cholesterol at 12 months compared to controls (MD -0.15 mmol/L, 95% CI -0.24 to -0.06; 1 RCT; n = 618; moderate-quality evidence), but may make little or no difference over longer time periods. Dietary counselling probably slightly decreased low-density lipoprotein (LDL) cholesterol at 12 months (MD -0.12 mmol/L, 95% CI -0.20 to -0.04; 1 RCT; n = 618, moderate-quality evidence) and at five years (MD -0.09, 95% CI -0.17 to -0.01; 1 RCT; n = 623; moderate-quality evidence), compared to controls. Dietary counselling probably made little or no difference to HDL-C at 12 months (MD -0.03 mmol/L, 95% CI -0.08 to 0.02; 1 RCT; n = 618; moderate-quality evidence), and at five years (MD -0.01 mmol/L, 95% CI -0.06 to 0.04; 1 RCT; n = 522; moderate-quality evidence). Likewise, counselling probably made little or no difference to triglycerides in children at 12 months (MD -0.01 mmol/L, 95% CI -0.08 to 0.06; 1 RCT; n = 618; moderate-quality evidence). Lower versus usual or modified fat intake may make little or no difference to height at seven years (MD -0.60 cm, 95% CI -2.06 to 0.86; 1 RCT; n = 577; low-quality evidence).Associations between total fat intake, weight and body fatness from cohort studiesOver half the cohort analyses that reported on primary outcomes suggested that as total fat intake increases, body fatness measures may move in the same direction. However, heterogeneous methods and reporting across cohort studies, and predominantly very low-quality evidence, made it difficult to draw firm conclusions and true relationships may be substantially different.

AUTHORS' CONCLUSIONS

We were unable to reach firm conclusions. Limited evidence from three trials that randomised children to dietary counselling or education to lower total fat intake (30% or less TE) versus usual or modified fat intake, but with no intention to reduce weight, showed small reductions in body mass index, total- and LDL-cholesterol at some time points with lower fat intake compared to controls. There were no consistent effects on weight, high-density lipoprotein (HDL) cholesterol or height. Associations in cohort studies that related total fat intake to later measures of body fatness in children were inconsistent and the quality of this evidence was mostly very low. Most studies were conducted in high-income countries, and may not be applicable in low- and middle-income settings. High-quality, longer-term studies are needed, that include low- and middle-income settings to look at both possible benefits and harms.

Effects of total fat intake on bodyweight in children

BACKGROUND

As part of efforts to prevent childhood overweight and obesity, we need to understand the relationship between total fat intake and body fatness in generally healthy children.

OBJECTIVES

To assess the effects of total fat intake on measures of weight and body fatness in children and young people not aiming to lose weight.

SEARCH METHODS

For this update we revised the previous search strategy and ran it over all years in the Cochrane Library, MEDLINE (Ovid), MEDLINE (PubMed), and Embase (Ovid) (current to 23 May 2017). No language and publication status limits were applied. We searched the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov for ongoing and unpublished studies (5 June 2017).

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in children aged 24 months to 18 years, with or without risk factors for cardiovascular disease, randomised to a lower fat (30% or less of total energy (TE)) versus usual or moderate-fat diet (greater than 30%TE), without the intention to reduce weight, and assessed a measure of weight or body fatness after at least six months. We included prospective analytical cohort studies in these children if they related baseline total fat intake to weight or body fatness at least 12 months later. We duplicated inclusion decisions and resolved disagreement by discussion with other authors.

DATA COLLECTION AND ANALYSIS

We extracted data on participants, interventions or exposures, controls and outcomes, and trial or cohort quality characteristics, as well as data on potential effect modifiers, and assessed risk of bias for all included studies. We extracted outcome data using the following time point ranges, when available: RCTs: baseline to six months, six to 12 months, one to two years, two to five years and more than five years; cohort studies: baseline to one year, one to two years, two to five years, five to 10 years and more than 10 years. We planned to perform random-effects meta-analyses with relevant subgrouping, and sensitivity and funnel plot analyses where data allowed.

MAIN RESULTS

We included 24 studies comprising three parallel-group RCTs (n = 1054 randomised) and 21 prospective analytical cohort studies (about 25,059 children completed). Twenty-three were conducted in high-income countries. No meta-analyses were possible, since only one RCT reported the same outcome at each time point range for all outcomes, and cohort studies were too heterogeneous.For the RCTs, concerns about imprecision and poor reporting limited our confidence in our findings. In addition, the inclusion of hypercholesteraemic children in two trials raised concerns about applicability. Lower versus usual or modified total fat intake may have made little or no difference to weight over a six- to twelve month period (mean difference (MD) -0.50 kg, 95% confidence interval (CI) -1.78 to 0.78; 1 RCT; n = 620; low-quality evidence), nor a two- to five-year period (MD -0.60 kg, 95% CI -2.39 to 1.19; 1 RCT; n = 612; low-quality evidence). Compared to controls, lower total fat intake (30% or less TE) probably decreased BMI in children over a one- to two-year period (MD -1.5 kg/m2, 95% CI -2.45 to -0.55; 1 RCT; n = 191; moderate-quality evidence), with no other differences evident across the other time points (two to five years: MD 0.00 kg/m2, 95% CI -0.63 to 0.63; 1 RCT; n = 541; greater than five years; MD -0.10 kg/m2, 95% CI -0.75 to 0.55; 1 RCT; n = 576; low-quality evidence). Lower fat intake probably slightly reduced total cholesterol over six to 12 months compared to controls (MD -0.15 mmol/L, 95% CI -0.24 to -0.06; 1 RCT; n = 618; moderate-quality evidence), but may make little or no difference over longer time periods. Lower fat intake probably slightly decreased low-density lipoprotein (LDL) cholesterol over six to 12 months (MD -0.12 mmol/L, 95% CI -0.20 to -0.04; 1 RCT; n = 618, moderate-quality evidence) and over two to five years (MD -0.09, 95% CI -0.17 to -0.01; 1 RCT; n = 623; moderate-quality evidence), compared to controls. However, lower total fat intake probably made little or no difference to HDL-C over a six- to 12-month period (MD -0.03 mmol/L, 95% CI -0.08 to 0.02; 1 RCT; n = 618; moderate-quality evidence), nor a two- to five-year period (MD -0.01 mmol/L, 95% CI -0.06 to 0.04; 1 RCT; n = 522; moderate-quality evidence). Likewise, lower total fat intake probably made little or no difference to triglycerides in children over a six- to 12-month period (MD -0.01 mmol/L, 95% CI -0.08 to 0.06; 1 RCT; n = 618; moderate-quality evidence). Lower versus usual or modified fat intake may make little or no difference to height over more than five years (MD -0.60 cm, 95% CI -2.06 to 0.86; 1 RCT; n = 577; low-quality evidence).Over half the cohort analyses that reported on primary outcomes suggested that as total fat intake increases, body fatness measures may move in the same direction. However, heterogeneous methods and reporting across cohort studies, and predominantly very low-quality evidence, made it difficult to draw firm conclusions and true relationships may be substantially different.

AUTHORS' CONCLUSIONS

We were unable to reach firm conclusions. Limited evidence from three trials that randomised children to a lower total fat intake (30% or less TE) versus usual or modified fat intake, but with no intention to reduce weight, showed small reductions in body mass index, total- and LDL-cholesterol at some time points with lower fat intake compared to controls, and no consistent differences in effects on weight, high-density lipoprotein (HDL) cholesterol or height. Associations in cohort studies that related total fat intake to later measures of body fatness in children were inconsistent and the quality of this evidence was mostly very low. Twenty-three out of 24 included studies were conducted in high-income countries, and may not be applicable in low- and middle-income settings. High-quality, longer-term studies are needed, that include low- and middle-income settings and look at both possible benefits and risks.

Health effects of saturated and trans-fatty acid intake in children and adolescents: Systematic review and meta-analysis

BACKGROUND

Elevated cholesterol has been linked to cardiovascular disease in adults and preclinical markers of atherosclerosis in children, thus reducing saturated (SFA) and trans-fatty acids (TFA) intake from an early age may help to reduce cholesterol and the risk of cardiovascular disease later in life. The aim of this review is to examine the evidence for health effects associated with reducing SFA and TFA intake in free-living children, adolescents and young adults between 2 to 19 years of age.

DESIGN

Systematic review and meta-analysis of randomised controlled trials (RCTs) and prospective cohort studies. Study selection, assessment, validity, data extraction, and analysis were undertaken as specified by the Cochrane Collaboration and the GRADE working group. Data were pooled using inverse variance models with random effects.

DATA SOURCES

EMBASE; PubMed; Cochrane Central Register of Controlled Trials; LILACS; and WHO Clinical Trial Registry (up to July 2016).

ELIGIBILITY CRITERIA FOR SELECTING TRIALS

RCTs involving dietary interventions aiming to reduce SFA or TFA intakes and a control group, and cohort studies reporting the effects of SFA or TFA exposures, on outcomes including blood lipids; measures of growth; blood pressure; insulin resistance; and potential adverse effects. Minimum duration was 13 days for RCTs and one year for cohort studies. Trials of weight loss or confounded by additional medical or lifestyle interventions were excluded.

RESULTS

Compared with control diets, there was a highly statistically significant effect of reduced SFA intake on total cholesterol (mean difference (MD) -0.16 mmol/l, [95% confidence interval (CI): -0.25 to -0.07]), LDL cholesterol (MD -0.13 mmol/l [95% CI:-0.22 to -0.03]) and diastolic blood pressure (MD -1.45 mmol/l [95% CI:-2.34 to -0.56]). There were no significant effects on any other risk factors and no evidence of adverse effects.

CONCLUSIONS

Advice to reduce saturated fatty acids intake of children results in a significant reduction in total and LDL-cholesterol levels as well as diastolic blood pressure without evidence of adverse effects on growth and development. Dietary guidelines for children and adolescents should continue to recommend diets low in saturated fat.

Effect of magnesium supplementation on blood rheology in NOS inhibition-induced hypertension model

This study investigated the effects of magnesium on blood rheological properties and blood pressure in nitric oxide synthase (NOS) inhibition-induced hypertension model. Hypertension was induced by oral administration of the nonselective NOS inhibitor N-nitro-L-arginine methyl ester (L-NAME, 25 mg/kg/day) for 6 weeks and systolic blood pressure was measured by the tail-cuff method. The groups receiving magnesium supplementation were fed with rat chow containing 0.8% magnesium oxide during the experiment. At the end of experiment, blood samples were obtained from abdominal aorta, using ether anesthesia. Plasma and erythrocyte magnesium levels were determined by the atomic absorption spectrometer. RBC deformability and aggregation were determined by rotational ektacytometry. Plasma fibrinogen concentration was evaluated by ELISA. Whole blood and plasma viscosities were determined by viscometer and intracellular free Ca++ level was measured by using spectroflurometric method. Blood pressure was elevated in hypertensive groups and suppressed by magnesium therapy. Plasma viscosity and RBC aggregation were found to be higher in hypertensive rats than control animals and these parameters significantly decreased in magnesium supplemented hypertensive animals. Other measurements were not different between experimental groups. These results confirm that blood pressure, plasma viscosity and RBC aggregation increased in NOS inhibition-induced hypertension model and oral magnesium supplementation improved these parameters.

Dietary intake and prospective changes in cardiometabolic risk factors in children and youth

Only few studies examined the effect of diet on prospective changes in cardiometabolic (CM) risk factors in children and youth despite its importance for understanding the role of diet early in life for cardiovascular disease in adulthood. To test the hypothesis that dietary intake is associated with prospective changes in CM risk factors, we analyzed longitudinal observations made over a period of 2 years among 448 students (aged 10-17 years) from 14 schools in Canada. We applied mixed effect regression to examine the associations of dietary intake at baseline with changes in body mass index, waist circumference (WC), systolic and diastolic blood pressure (SBP and DBP), and insulin sensitivity score between baseline and follow-up while adjusting for age, sex, and physical activity. Dietary fat at baseline was associated with increases in SBP and DBP z scores (per 10 g increase in dietary fat per day: β = 0.03; p < 0.05) and WC (β = 0.31 cm; p < 0.05) between baseline and follow-up. Every additional gram of sodium intake at baseline was associated with an increase in DBP z score of 0.04 (p < 0.05) between baseline and follow-up. Intake of sugar, vegetables and fruit, and fibre were not associated with changes in CM risk factors in a statistically significant manner. Our findings suggest that a reduction in the consumption of total dietary fat and sodium may contribute to the prevention of excess body weight and hypertension in children and youth, and their cardiometabolic sequelae later in life.

A Western dietary pattern is associated with higher blood pressure in Iranian adolescents

PURPOSE

The dietary determinants of adolescent blood pressure (BP) are not well understood. We determined the association between major dietary patterns and BP in a sample of Iranian adolescents.

METHODS

This cross-sectional study was conducted among a representative sample (n = 557) of Shirazi adolescents aged 12-19 years. Participants' systolic and diastolic BP was measured using a validated oscillometric BP monitor. Usual dietary intakes during the past 12 months were assessed using a valid and reproducible 168-item semiquantitative food frequency questionnaire through face-to-face interviews. Principal component factor analysis was used to identify major dietary patterns based on a set of 25 predefined food groups.

RESULTS

Overall, three major dietary patterns were identified, among which only the Western pattern (abundant in soft drinks, sweets and desserts, salt, mayonnaise, tea and coffee, salty snacks, high-fat dairy products, French fries, and red or processed meats) had a significant association with BP. After adjusting for potential confounders in the analysis of covariance models, multivariable adjusted means of the systolic and mean BP of subjects in the highest tertile of the Western pattern score were significantly higher than those in the lowest tertile (for systolic BP: mean difference 6.9 mmHg, P = 0.001; and for mean BP: mean difference 4.2 mmHg, P = 0.003). A similar but statistically insignificant difference was observed in terms of diastolic BP.

CONCLUSIONS

The findings suggest that a Western dietary pattern is associated with higher BP in Iranian adolescents. However, additional large-scale prospective studies with adequate methodological quality are required to confirm these findings.

Magnesium in disease

Although the following text will focus on magnesium in disease, its role in healthy subjects during physical exercise when used as a supplement to enhance performance is also noteworthy. Low serum magnesium levels are associated with metabolic syndrome, Type 2 diabetes mellitus (T2DM) and hypertension; consequently, some individuals benefit from magnesium supplementation: increasing magnesium consumption appears to prevent high blood pressure, and higher serum magnesium levels are associated with a lower risk of developing a metabolic syndrome. There are, however, conflicting study results regarding magnesium administration with myocardial infarction with and without reperfusion therapy. There was a long controversy as to whether or not magnesium should be given as a first-line medication. As the most recent trials have not shown any difference in outcome, intravenous magnesium cannot be recommended in patients with myocardial infarction today. However, magnesium has its indication in patients with torsade de pointes and has been given successfully to patients with digoxin-induced arrhythmia or life-threatening ventricular arrhythmias. Magnesium sulphate as an intravenous infusion also has an important established therapeutic role in pregnant women with pre-eclampsia as it decreases the risk of eclamptic seizures by half compared with placebo.

Pacific kids DASH for health (PacDASH) randomized, controlled trial with DASH eating plan plus physical activity improves fruit and vegetable intake and diastolic blood pressure in children

BACKGROUND

Pacific Kids DASH for Health (PacDASH) aimed to improve child diet and physical activity (PA) level and prevent excess weight gain and elevation in blood pressure (BP) at 9 months.

METHODS

PacDASH was a two-arm, randomized, controlled trial (ClinicalTrials.gov: NCT00905411). Eighty-five 5- to 8-year-olds in the 50th-99th percentile for BMI were randomly assigned to treatment (n=41) or control (n=44) groups; 62 completed the 9-month trial. Sixty-two percent were female. Mean age was 7.1±0.95 years. Race/ethnicity was Asian (44%), Native Hawaiian or Other Pacific Islander (28%), white (21%), or other race/ethnicity (7%). Intervention was provided at baseline and 3, 6 and 9 months, with monthly supportive mailings between intervention visits, and a follow-up visit at 15 months to observe maintenance. Diet and PA were assessed by 2-day log. Body size, composition, and BP were measured. The intervention effect on diet and PA, body size and composition, and BP by the end of the intervention was tested using an F test from a mixed regression model, after adjustment for sex, age, and ethnic group.

RESULTS

Fruit and vegetable (FV) intake decreased less in the treatment than control group (p=0.04). Diastolic BP (DBP) was 12 percentile units lower in the treatment than control group after 9 months of intervention (p=0.01). There were no group differences in systolic BP (SBP) or body size/composition.

CONCLUSIONS

The PacDASH trial enhanced FV intake and DBP, but not SBP or body size/composition.

Effects of protein intake on blood pressure, insulin sensitivity and blood lipids in children: a systematic review

High protein intake in early childhood is associated with obesity, suggesting possible adverse effects on other cardiometabolic outcomes. However, studies in adults have suggested beneficial effects of protein intake on blood pressure (BP) and lipid profile. Whether dietary protein intake is associated with cardiovascular and metabolic health in children is unclear. Therefore, we aimed to systematically review the evidence on the associations of protein intake with BP, insulin sensitivity and blood lipids in children. We searched the databases Medline, Embase, Cochrane Central and PubMed for interventional and observational studies in healthy children up to the age of 18 years, in which associations of total, animal and/or vegetable protein intake with one or more of the following outcomes were reported: BP; measures of insulin sensitivity; cholesterol levels; or TAG levels. In the search, we identified 6636 abstracts, of which fifty-six studies met all selection criteria. In general, the quality of the included studies was low. Most studies were cross-sectional, and many did not control for potential confounders. No overall associations were observed between protein intake and insulin sensitivity or blood lipids. A few studies suggested an inverse association between dietary protein intake and BP, but evidence was inconclusive. Only four studies examined the effects of vegetable or animal protein intake, but with inconsistent results. In conclusion, the literature, to date provides insufficient evidence for effects of protein intake on BP, insulin sensitivity or blood lipids in children. Future studies could be improved by adequately adjusting for key confounders such as energy intake and obesity.

An inverse association between magnesium in 24-h urine and cardiovascular risk factors in middle-aged subjects in 50 CARDIAC Study populations

Serum, plasma and dietary magnesium (Mg) have been reported to be inversely associated with cardiovascular disease risk factors. We examined the associations between the 24-h urinary Mg/creatinine (Cre) ratio and cardiovascular disease risk factors, such as body mass index (BMI), blood pressure (BP), serum total cholesterol (TC) and prevalence of obesity, hypertension and hypercholesterolemia. A cross-sectional analysis was conducted among 4211 participants (49.7% women) aged 48-56 years in 50 population samples from 22 countries in the World Health Organization-coordinated Cardiovascular Diseases and Alimentary Comparison (CARDIAC) Study (1985-1994). In linear regression analyses, Mg/Cre ratio was inversely associated with BMI, systolic BP (SBP), diastolic BP (DBP) and TC (P for linear trend <0.001 for each). These associations were not markedly altered by adjustment for traditional risk factors, urinary markers or cohort effects. Multivariate-adjusted mean values for the subjects in the highest Mg/Cre ratio quintile were 6.3, 3.4, 5.3 and 4.6% lower than those for the subjects in the lowest quintile for BMI, SBP, DBP and TC (P < 0.001, respectively). The prevalence of obesity, hypertension and hypercholesterolemia was 2.10 (95% confidence interval: 1.50, 2.95), 1.55 (1.25, 1.92) and 2.06 (1.63, 2.62) times higher (P < 0.001, respectively) among the subjects in the lowest Mg/Cre ratio quintile than in the subjects in the highest quintile. These associations were not appreciably altered by adjustment for potential confounding variables. In conclusion, higher 24-h urinary Mg/Cre ratio was associated with lower cardiovascular disease risk factors, including BMI, BP, TC, obesity, hypertension and hypercholesterolemia.

Pediatric hypertension: An update on a burning problem

A large number of adults worldwide suffer from essential hypertension, and because blood pressures (BPs) tend to remain within the same percentiles throughout life, it has been postulated that hypertensive pressures can be tracked from childhood to adulthood. Thus, children with higher BPs are more likely to become hypertensive adults. These “pre-hypertensive” subjects can be identified by measuring arterial BP at a young age, and compared with age, gender and height-specific references. The majority of studies report that 1 to 5% of children and adolescents are hypertensive, defined as a BP > 95^th percentile, with higher prevalence rates reported for some isolated geographic areas. However, the actual prevalence of hypertension in children and adolescents remains to be fully elucidated. In addition to these young “pre-hypertensive” subjects, there are also children and adolescents with a normal-high BP (90^th-95^th percentile). Early intervention may help prevent the development of essential hypertension as they age. An initial attempt should be made to lower their BP by non-pharmacologic measures, such as weight reduction, aerobic physical exercise, and lowered sodium intake. A pharmacological treatment is usually needed should these measures fail to lower BP. The majority of antihypertensive drugs are not formulated for pediatric patients, and have thus not been investigated in great detail. The purpose of this review is to provide an update concerning juvenile hypertension, and highlight recent developments in epidemiology, diagnostic methods, and relevant therapies.

An update on the cardiovascular pleiotropic effects of milk and milk products

Hypertension is a major risk factor in addition to atherosclerosis and type 2 diabetes mellitus for the development of coronary heart disease and strokes. Several prospective clinical studies have demonstrated a possible protective effect of milk and dairy product consumption on these conditions. The putative effects of milk and dairy products are possibly mediated through their mineral content of calcium, magnesium, potassium, and vitamin D. These dairy substances exercise their blood pressure-lowering effect either directly on the arterial wall by these minerals or indirectly through blockade of the angiotensin-converting enzyme (ACE) by the amino acids contained in the casein and whey of milk. The blockade of ACE results in the inhibition of production of angiotensin II, a potent vasoconstrictive peptide, and the prevention of degradation of bradykinin, a potent vasodilating peptide. For this concise review, a Medline search of the English language literature was conducted from 2006 to September 2012 and 16 pertinent papers were selected. The potential beneficial pleiotropic effects from these studies together with collateral literature will be discussed in this review.

Higher protein diets consumed ad libitum improve cardiovascular risk markers in children of overweight parents from eight European countries

Dietary strategies to improve early cardiovascular markers in overweight children are needed. We investigated the effect of dietary protein and glycemic index (GI) on cardiovascular markers and metabolic syndrome (MetS) scores in 5- to 18-y-old children of overweight/obese parents from 8 European centers. Families were randomized to 1 of 5 diets consumed ad libitum: high protein (HP) or low protein (LP) combined with high GI (HGI) or low GI (LGI), or a control diet. At 6 centers, families received dietary instruction (instruction centers); at 2 centers, free foods were also provided (supermarket centers). Diet, anthropometry, blood pressure, and serum cardiovascular markers (lipid profile, glucose regulation, and inflammation) were measured in 253 children at baseline, 1 mo, and/or 6 mo. Protein intake was higher in the HP groups (19.9 ± 1.3% energy) than in the LP groups at 6 mo (16.8 ± 1.2% energy) (P = 0.001). The GI was 4.0 points lower (95% CI: 2.1, 6.1) in the LGI compared with the HGI groups (P < 0.001). In the supermarket centers, the HP and LP groups differed more in protein intake than did the groups in the instruction centers (P = 0.009), indicating better compliance. The HP diets evoked a 2.7-cm (95% CI: 0.9, 5.1) smaller waist circumference and a 0.25-mmol/L (95% CI: 0.09, 0.41) lower serum LDL cholesterol compared with the LP diets at 6 mo (P < 0.007). In a separate supermarket center analysis, the HP compared with LP diets reduced waist circumference (P = 0.004), blood pressure (P < 0.01), serum insulin (P = 0.013), and homeostasis model of assessment-insulin resistance (P = 0.016). In the instruction centers, the HP compared with the LP diets reduced LDL cholesterol (P = 0.004). No consistent effect of GI was seen and the MetS scores were not affected. In conclusion, increased protein intake improved cardiovascular markers in high-risk children, particularly in those undergoing most intensive intervention.

Impact of nutrition since early life on cardiovascular prevention

The cardiovascular disease represents the leading cause of morbidity and mortality in Western countries and it is related to the atherosclerotic process. Cardiovascular disease risk factors, such as dyslipidemia, hypertension, insulin resistance, obesity, accelerate the atherosclerotic process which begins in childhood and progresses throughout the life span. The cardiovascular disease risk factor detection and management through prevention delays the atherosclerotic progression towards clinical cardiovascular disease. Dietary habits, from prenatal nutrition, breastfeeding, complementary feeding to childhood and adolescence nutrition play a basic role for this topic.

The metabolic and neuroendocrine environment of the fetus is fundamental in the body’s “metabolic programming”. Further several studies have demonstrated the beneficial effects of breastfeeding on cardiovascular risk factors reduction. Moreover the introduction of complementary foods represents another important step, with particular regard to protein intake. An adequate distribution between macronutrients (lipids, proteins and carbohydrates) is required for correct growth development from infancy throughout adolescence and for prevention of several cardiovascular disease risk determinants in adulthood.

The purpose of this review is to examine the impact of nutrition since early life on disease.

La malattia cardiovascolare rappresenta la principale causa di morbilità e mortalità dei paesi occidentali ed è correlata a degenerazione vascolare aterosclerotica. I fattori di rischio cardiovascolari quali dislipidemia, ipertensione, insulino resistenza e obesità accelerano tale processo il cui esordio è noto sin dell’età pediatrica ed evolve nel corso della vita. L’individuazione e la cura dei fattori di rischio cardiovascolari mediante la prevenzione dei fattori causali ritardano la progressione dell’aterosclerosi e l’insorgenza dei sintomi cardiovascolari. La nutrizione svolge un ruolo preventivo fondamentale sin dall’epoca prenatale e nelle diverse età della crescita.

La condizione metabolica e neuro-endocrino cui è sottoposto il feto è rilevante per la “programmazione metabolica”. E’ dimostrata inoltre l’importanza delle modalità di allattamento e divezzamento con particolare interesse per l’assunzione di proteine nel controllo dei fattori di rischio cardiovascolari. La corretta distribuzione di macronutrienti (lipidi, proteine e carboidrati) dall’infanzia all’adolescenza favorisce una crescita corretta e risulta utile a prevenire l’insorgenza dei determinanti di rischio di malattia cardiovascolare in età adulta.

Nella presente review verrà esaminato l’impatto della nutrizione dalle più precoci fasi delle vita sul rischio cardiovascolare.

Is hypomagnesaemia a coronary risk factor among Indians with coronary artery disease?

Introduction:

Magnesium is an essential element that has numerous biological functions in the cardiovascular system. Hence, three hundred patients with known cardiovascular disease above the age of 25 years were studied to evaluate association between dietary and serum magnesium with cardiovascular risk factors.

Materials and Methods:

Patients were divided into three groups according to serum magnesium levels; ≤1.6 (Group 1), >1.6-2.6 (Group 2) and: >2.6 mg/dl (Group 3), and into two groups according to dietary magnesium intake; ≤350 mg/day (Group 1) and >350 mg/day (Group 2), respectively.

Results:

Mean age of patients was 60.97 ± 12.5 years. Total cholesterol, triglycerides, VLDL, and LDL were significantly higher and HDL cholesterol significantly lower in group 1 when compared with group 2 and group 3. Diabetes, dyslipidemia, and hypertension were negatively correlated with serum magnesium levels; which were maintained even after adjustment with age, sex, and anthropometric parameters in multiple regression analysis. Similar observations were observed in dietary magnesium intake except LDL and total cholesterol. Dietary magnesium was positively correlated with serum magnesium.

Conclusions:

Hypomagnesaemia and low dietary intake of magnesium are strongly related to cardiovascular risk factors among known subjects with coronary artery disease. Hence, magnesium supplementation may help in reducing cardiovascular disease.

Evidence-based guideline of the German Nutrition Society: carbohydrate intake and prevention of nutrition-related diseases

The relative contribution of nutrition-related chronic diseases to the total disease burden of the society and the health care costs has risen continuously over the last decades. Thus, there is an urgent necessity to better exploit the potential of dietary prevention of diseases. Carbohydrates play a major role in human nutrition - next to fat, carbohydrates are the second biggest group of energy-yielding nutrients. Obesity, type 2 diabetes mellitus, dyslipoproteinaemia, hypertension, metabolic syndrome, coronary heart disease and cancer are wide-spread diseases, in which carbohydrates could have a pathophysiologic relevance. Correspondingly, modification of carbohydrate intake could have a preventive potential. In the present evidence-based guideline of the German Nutrition Society, the potential role of carbohydrates in the primary prevention of the named diseases was judged systematically. The major findings were: a high carbohydrate intake at the expense of total fat and saturated fatty acids reduces the concentrations of total, LDL and HDL cholesterol. A high carbohydrate consumption at the expense of polyunsaturated fatty acids increases total and LDL cholesterol, but reduces HDL cholesterol. Regardless of the type of fat being replaced, a high carbohydrate intake promotes an increase in the triglyceride concentration. Furthermore, a high consumption of sugar-sweetened beverages increases the risk of obesity and type 2 diabetes mellitus, whereas a high dietary fibre intake, mainly from whole-grain products, reduces the risk of obesity, type 2 diabetes mellitus, dyslipoproteinaemia, cardiovascular disease and colorectal cancer at varying evidence levels. The practical consequences for current dietary recommendations are presented.

The effect of dairy consumption on blood pressure in mid-childhood: CAPS cohort study

BACKGROUND/OBJECTIVES

It has been postulated that a higher dairy consumption may affect blood pressure regulation. The aim of this study was to examine the association between dairy consumption and blood pressure in mid-childhood.

SUBJECTS/METHODS

Subjects (n = 335) were participants of a birth cohort at high risk of asthma with information on diet at 18 months and blood pressure at 8 years. Multivariate analyses were used to assess the association of dairy consumption (serves) and micronutrient intakes (mg). In a subgroup of children (n = 201), dietary intake was also measured at approximately 9 years.

RESULTS

Children in the highest quintile of dairy consumption at 18 months had lower systolic blood pressure (SBP) and diastolic blood pressure (DBP) at 8 years (2.5 mm Hg, P=0.046 and 1.9 mm Hg, P = 0.047, respectively) than those in the lowest quintiles. SBP was lowest among children in the highest quintiles of calcium, magnesium and potassium intakes. Significant negative linear trends were observed between SBP and intakes of dairy serves, calcium, magnesium and potassium. Furthermore, SBP and DBP were lowest in the group of children that consumed at least two dairy serves at both 18 months and the follow-up dietary data collection at 9 years, compared with all other children (SBP 98.7 vs 101.0 mm Hg, P = 0.07; and DBP 56.5 vs 59.3 mm Hg, P = 0.006, respectively).

CONCLUSION

These results are consistent with a protective effect of dairy consumption in childhood on blood pressure at age 8 years.

Fiber, protein, and lupin-enriched foods: role for improving cardiovascular health

Cardiovascular diseases (CVD) are the leading cause of death globally (World Health Organisation, 2011). Many of the risk factors for CVD are modifiable, including overweight and obesity. Numerous strategies have been proposed to fight CVD, with a special focus being placed on dietary interventions for weight management. The literature suggests that two nutrients, fiber and protein, may play significant roles in weight control and hence cardiovascular health. Increasing both protein and fiber in the diet can be difficult because popular low-carbohydrate and high-protein diets tend to have considerably low-fiber intakes (Slavin, 2005). One approach to obtain both is to develop functional foods using unique ingredients. Lupin flour is a novel food ingredient derived from the endosperm of lupin. It contains 40-45% protein, 25-30% fiber, and negligible sugar and starch (Petterson and Crosbie, 1990). Research conducted to date reveals that lupin-enriched foods, which are naturally high in protein and fiber, may have a significant effect on CVD risk factors. This review explores whether there is a role for fiber-, protein-, and lupin-enriched foods in improving cardiovascular health.

Adolescent diet and metabolic syndrome in young women: results of the Dietary Intervention Study in Children (DISC) follow-up study

CONTEXT

Childhood diet is hypothesized to influence development of chronic disease in adulthood.

OBJECTIVE

Our objective was to evaluate the long-term effects of a dietary intervention to reduce fat and increase fiber intake during childhood and adolescence on the prevalence of metabolic syndrome in young adult women.

DESIGN

A follow-up study was conducted in 2006-2008, 9 yr after termination of the Dietary Intervention Study in Children (DISC).

SETTING

The study took place at six DISC clinical centers in the United States.

PARTICIPANTS

A total of 230 (76%) DISC female participants who were 25-29 yr old and had not been pregnant or breastfeeding in the previous 3 months participated in the follow-up study.

INTERVENTION

There was no intervention between the end of the DISC trial and the follow-up visit.

MAIN OUTCOME MEASURE

Metabolic syndrome was the primary study endpoint planned before data collection and was hypothesized to be less common in the intervention group participants.

RESULTS

Metabolic syndrome was uncommon, and its prevalence did not differ by treatment group. However, after adjustment for nondietary variables, mean systolic blood pressures of intervention and control group participants were 107.7 and 110.0 mm Hg, respectively (P = 0.03), whereas mean fasting plasma glucose levels were 87.0 and 89.1 mg/dl, respectively (P = 0.01). Intervention group participants also had lower concentrations of large very-low-density lipoprotein particles, a marker of hepatic insulin resistance, compared with control group participants. Adjustment for current diet did not materially alter results.

CONCLUSION

Consumption of a diet lower in fat and higher in fiber during childhood and adolescence may benefit glycemic control and blood pressure long term.

Enabling and empowering--the need for an integrated approach to address hypertension among African adults

This paper charts analytic and conceptual debates on the burden of hypertension among Africans and the interlocking role of diet and genetic factors. The discussions in this paper are about (indigenous) rather than (white) Africans. In trying to show understanding in the issues raised within this paper, the debate highlights the increasing burden of hypertension in Africans. The paper also mentions the role of adverse factors over the life course on hypertension, which is described in public health literature as a widespread burden. It also mentions that there appears to be an increasing prevalence of high blood pressure among Africans explained by widespread nutrition transitions to lipid-rich diets and a decrease in physical activity; as a result, hypertension has become a ubiquitous cause of morbidity and contributor to mortality among Africans. While these issues are acknowledged, the authors argue that it is not enough to think that persuading and encouraging poorer households to purchase 'cheap' and less fatty foods will address nutritional problems. It is one thing making food available and it is another putting the food basket on the table. Both conditions require negotiations of complex political, social, economic, cultural and environmental hurdles. What is needed is reorienting existing health care systems to meet these challenges while empowering and saturating African populations and households with systematic but intense health information, education and communication.

Saturated fat, carbohydrate, and cardiovascular disease

A focus of dietary recommendations for cardiovascular disease (CVD) prevention and treatment has been a reduction in saturated fat intake, primarily as a means of lowering LDL-cholesterol concentrations. However, the evidence that supports a reduction in saturated fat intake must be evaluated in the context of replacement by other macronutrients. Clinical trials that replaced saturated fat with polyunsaturated fat have generally shown a reduction in CVD events, although several studies showed no effects. An independent association of saturated fat intake with CVD risk has not been consistently shown in prospective epidemiologic studies, although some have provided evidence of an increased risk in young individuals and in women. Replacement of saturated fat by polyunsaturated or monounsaturated fat lowers both LDL and HDL cholesterol. However, replacement with a higher carbohydrate intake, particularly refined carbohydrate, can exacerbate the atherogenic dyslipidemia associated with insulin resistance and obesity that includes increased triglycerides, small LDL particles, and reduced HDL cholesterol. In summary, although substitution of dietary polyunsaturated fat for saturated fat has been shown to lower CVD risk, there are few epidemiologic or clinical trial data to support a benefit of replacing saturated fat with carbohydrate. Furthermore, particularly given the differential effects of dietary saturated fats and carbohydrates on concentrations of larger and smaller LDL particles, respectively, dietary efforts to improve the increasing burden of CVD risk associated with atherogenic dyslipidemia should primarily emphasize the limitation of refined carbohydrate intakes and a reduction in excess adiposity.

Dietary determinants of subclinical inflammation, dyslipidemia and components of the metabolic syndrome in overweight children: a review

OBJECTIVE

To review and summarize the dietary determinants of the metabolic syndrome, subclinical inflammation and dyslipidemia in overweight children.

DESIGN

Review of the current literature, focusing on pediatric studies.

PARTICIPANTS

Normal weight, overweight, or obese children and adolescents.

RESULTS

There is a growing literature on the metabolic effects of excess body fat during childhood. However, few pediatric studies have examined the dietary determinants of obesity-related metabolic disturbances. From the available data, it appears that dietary factors are not only important environmental determinants of adiposity, but also may affect components of the metabolic syndrome and modulate the actions of adipokines. Dietary total fat and saturated fat are associated with insulin resistance and high blood pressure, as well as obesity-related inflammation. In contrast to studies in adults, resistin and adiponectin do not appear to be closely linked to insulin resistance or dyslipidemia in childhood. However, circulating leptin and retinol-binding protein (RBP) 4 correlate well with obesity, central obesity and the metabolic syndrome in children. Intakes of antioxidant vitamins tend to be low in obese children and may be predictors of subclinical inflammation. Higher fructose intake from sweets and sweetened drinks in overweight children has been linked to decreased low-density lipoprotein (LDL) particle size.

CONCLUSIONS

Dietary interventions aimed at reducing intakes of total fat, saturated fat and free fructose, whereas increasing antioxidant vitamin intake may be beneficial in overweight children. More research on the relationships between dietary factors and the metabolic changes of pediatric obesity may help to identify the dietary changes to reduce health risks.

Clinical and laboratory assessment of cardiovascular risk in children: Guidelines for screening, evaluation, and treatment

The early lesions of atherosclerosis begin in childhood and are related to antecedent cardiovascular disease (CVD) risk factors. Environmental and genetic factors (eg, diet, obesity, exercise, and certain inherited dyslipidemias) influence progression of such lesions. Identification of youth at risk for atherosclerosis includes an integrated assessment of these predisposing factors. Treatment starts with a diet low in total and saturated fat and cholesterol, use of water-soluble fiber, plant stanols and plant sterols, weight control, and exercise. Drug therapy, for example, with inhibitors of hydroxymethylglutaryl-CoA reductase, bile acid sequestrants, and cholesterol absorption inhibitors, can be considered in those with a positive family history of premature CVD and low-density lipoprotein cholesterol >160 mg/dL after dietary and hygienic measures. Candidates for drug therapy often include those with familial hypercholesterolemia, familial combined hyperlipidemia, the metabolic syndrome, polycystic ovarian syndrome, type 1 diabetes, and the nephrotic syndrome. Such dietary and drug therapy appears safe and efficacious. Early identification and treatment of youth with CVD risk factors and dyslipidemia are likely to retard the atherosclerotic process. Optimal detection and treatment of high-risk children either from the general population or from families with premature CVD will require a comprehensive universal screening and evaluation program.

Evidence of infant blood pressure programming by maternal nutrition during pregnancy: a prospective randomized controlled intervention study

OBJECTIVES

To evaluate the impact of maternal nutrition during pregnancy on infant blood pressure.

STUDY DESIGN

Pregnant women (n = 256) were randomized into 3 groups: modified dietary intake according to current recommendations and probiotics (diet/probiotics), placebo (diet/placebo), and a control/placebo group. In the infants born to these women, blood pressure was recorded at age 6 months using an automated oscillometric DINAMAP R.

RESULTS

Despite significant differences in maternal dietary intakes between the study groups, the intervention focusing on maternal fat intake showed no direct impact on infants' blood pressure. Instead, a complex U-shaped interrelationship was uncovered; the highest and lowest quartiles of intakes of specific nutrients, carbohydrate (P = .006 for systolic pressure and P = .015 for diastolic pressure), and monounsaturated fatty acids (P = .029 for diastolic pressure) compared with the middle quartiles resulted in higher blood pressure at age 6 months. The pattern between maternal carbohydrate intake during pregnancy and infants' blood pressure remained significant even after adjustment for breastfeeding and body length. A reverse U-shaped trend again was observed between maternal intake of fruits and infants' systolic blood pressure (P = .077).

CONCLUSION

With a view toward programming blood pressure to adulthood, our results suggest an opportunity for dietary counseling to promote child health.

Protein intake and blood pressure in cardiovascular disease

Raised blood pressure (BP) is a major cause of CHD and the leading cause of stroke. Although BP rises with age in most populations, there are remote populations around the world where BP does not rise with age and where the high prevalence of high BP and frank hypertension seen in the UK and other Western countries in the older age-groups is not found. However, when such populations migrate to urban settings, their BPs rise, indicating that the population-wide BP problem is largely environmental in origin. Thus, a substantial body of evidence has accumulated on the importance of dietary factors in BP (Na and alcohol intakes (direct relationship) and K intake (inverse relationship)) as well as body weight (direct relationship). More recently, attention has shifted to other dietary factors that might affect BP. Data from studies of vegetarians (who tend to have lower BP than meat-eating populations) as well as clinical data on the adverse effects of protein intake in patients with renal insufficiency led to the view in Western countries that dietary (animal or total) protein had an adverse effect on BP. By contrast, studies in Japan and China suggested that dietary protein might be protective of high BP and stroke. Recent epidemiological studies have found inverse associations between dietary protein intake and BP, consistent with this view, and supported by some evidence from animal studies. Recent controlled clinical trials of soyabean supplementation have also suggested a BP-lowering effect of protein intake. Results of further large-scale epidemiological studies of protein and BP are awaited.

Dietary and lifestyle factors associated with blood pressure among U.S. adolescents

PURPOSE

To identify modifiable lifestyle factors associated with blood pressure among U.S. adolescents.

METHODS

A cross-sectional study was conducted of 4508 12-19-year-old respondents of the 1999-2002 National Health and Nutrition Examination Survey. Systolic and diastolic blood pressure (SBP and DBP) were measured and adjusted for gender, age, and height using z-scores (SBPZ and DBPZ). Body mass index (BMI) was adjusted for gender and age (BMIZ). Questionnaires were used to measure nutrient intake (carbohydrate, protein, saturated and unsaturated fat, sodium, potassium, calcium, magnesium, fiber, and caffeine) and activities (physical activities and sedentary activities, including television watching).

RESULTS

In the adjusted model (R2 = .115), SBPZ was higher by .022 standard deviation (SD) (95% confidence interval [CI]: .007-.038, equivalent to approximately .2 mmHg) per 1-hour increments in sedentary activities; higher by .244 SD (.198-.289, approximately 2.6 mmHg) per 1 SD of BMIZ; and lower by .099 SD (-.192 to -.006, approximately 1.1 mmHg) per 100 g of carbohydrate intake. Unexpectedly, BMIZ was negatively associated with DBPZ (-.078 per 1 SD, -.114 to -.043, approximately .9 mmHg).

CONCLUSIONS

Among U.S. adolescents, sedentary activities and BMI are positively associated with SBP after adjustment for confounding factors and mediators, while BMI is negatively associated with DBP. If confirmed by further studies, population-based interventions aimed at sedentary activities may be practical approaches to decrease SBP and the risk of obesity among adolescents.

Health and nutrition education program in primary schools of Crete: changes in blood pressure over 10 years

OBJECTIVE

To examine the long-term effects of the 'Cretan Health and Nutrition Education Program' on blood pressure.

SUBJECTS

A representative population of 176 pupils (85 from the intervention schools and 91 from the control schools).

DESIGN

Blood pressure, dietary, anthropometrical and physical activity data were obtained at baseline (academic year 1992-1993) and at follow-up examination (academic year 2001-2002).

RESULTS

The findings of the current study revealed that the increase over the 10-year period in systolic (SBP) and diastolic blood pressure (DBP) was higher in the control group (CG) than in the intervention group (IG) (P=0.003 and P<0.001 respectively). Regarding dietary indices, the IG were found to have a significantly higher intake of potassium (P=0.018) and magnesium (P=0.011) compared to the CG. Furthermore, the decrease in body mass index (BMI) z-score observed in the IG was found to differentiate significantly from the increase observed in the CG (P=0.042). On the contrary, the increase in leisure time, moderate to vigorous physical activities (MVPA) observed in the IG, was found to differentiate significantly from the decrease observed in the CG (P=0.032). Intervention's effect on SBP was mediated by changes in MVPA (beta=-0.20, P=0.030) and BMI (beta=0.19, P=0.048). Similarly, intervention's effect on DBP was mediated by changes in MVPA (beta=-0.18, P=0.048), BMI (beta=0.26, P=0.007) and magnesium intake (beta=-0.20, P=0.048).

CONCLUSION

The findings of the current study are encouraging, indicating favorable changes in blood pressure, micronutrients intake, BMI and physical activity over the 10 years of follow-up and 4 years after program's cessation, thus providing some support for the effectiveness of school-based health education programs in successfully tackling certain chronic disease risk factors early in life.

Vegetable protein and fiber from cereal are inversely associated with the risk of hypertension in a Spanish cohort

BACKGROUND

Some cross-sectional studies suggest that fiber and protein intake can be associated with lower levels of blood pressure, but results from prospective cohorts are scarce and none has been conducted outside the U.S.

METHODS

The SUN cohort followed-up prospectively 5880 Spanish men and women older than 20 years of age, all university graduates. Dietary information was gathered at baseline with a previously validated semiquantitative food frequency questionnaire. New cases of medically diagnosed hypertension (HT) were identified through responses to a mailed questionnaire after at least 2 years from recruitment.

RESULTS

One hundred and eighty new cases of HT were ascertained after a median follow-up of 28 months. After adjustment for potential confounders and several dietary factors, participants in the highest quintile of vegetable protein intake had a lower risk of incident HT compared with those in the lowest quintile [hazard ratio (HR) = 0.5, 95% confidence interval (CI) 0.2-0.9, p for trend = 0.06]. Similarly, fiber from cereals was inversely associated with a lower risk of HT (HR comparing fifth vs. first quintile = 0.6, 95% CI 0.3-1.0, p for trend = 0.05). Risk reduction was more important among men and obese and older individuals. Total or animal protein and total fiber as well as fiber from other sources different from cereal were not associated with the risk of HT.

CONCLUSIONS

In this Mediterranean cohort, dietary intake of vegetable protein and fiber from cereals was associated with a lower risk of HT when other nutrients were also taken into consideration.

Dietary Calcium as a Potential Modifier of the Relationship of Lead Burden to Blood Pressure

BACKGROUND

Cumulative lead burden and low dietary calcium have been independently associated with increased risk of hypertension. There is evidence of an interaction between these factors. We tested the hypothesis that dietary calcium intake modifies the relationship between lead burden and hypertension.

METHODS

A total of 471 men from the Normative Aging Study were evaluated. Bone lead was assessed using a K-x-ray fluorescence instrument, and information on dietary calcium intake was obtained with a self-administered semiquantitative food frequency questionnaire.

RESULTS

We categorized 259 subjects (55%) as having low calcium intake (< or =800 mg/d) and 212 subjects (45%) as having higher calcium intake. In logistic regression models stratified by dietary calcium intake, tibia lead had a weak association with hypertension among subjects with low dietary calcium (odds ratio for 1-standard deviation increase in tibia lead = 1.30; 95% confidence interval = 0.97-1.74) but not in subjects with higher dietary calcium intake. Similarly, blood lead was associated with hypertension only in subjects with low calcium intake. We also found evidence of an interaction between dietary calcium intake and body mass index.

CONCLUSIONS

High bone and blood lead increased the likelihood of hypertension, particularly among subjects with low dietary calcium intake. Dietary calcium may be helpful in prevention of hypertension induced by elevated lead burden.

Role of magnesium in hypertension

Magnesium affects blood pressure by modulating vascular tone and reactivity. It acts as a calcium channel antagonist, it stimulates production of vasodilator prostacyclins and nitric oxide and it alters vascular responses to vasoactive agonists. Magnesium deficiency has been implicated in the pathogenesis of hypertension with epidemiological and experimental studies demonstrating an inverse correlation between blood pressure and serum magnesium levels. Magnesium also influences glucose and insulin homeostasis, and hypomagnesemia is associated with metabolic syndrome. Although most epidemiological and experimental studies support a role for low magnesium in the pathophysiology of hypertension, data from clinical studies have been less convincing. Furthermore, the therapeutic value of magnesium in the management of hypertension is unclear. The present review addresses the role of magnesium in the regulation of vascular function and blood pressure and discusses the implications of magnesium deficiency in experimental and clinical hypertension, in metabolic syndrome and in pre-eclampsia.

Dietary recommendations for children and adolescents: a guide for practitioners

Since the American Heart Association last presented nutrition guidelines for children, significant changes have occurred in the prevalence of cardiovascular risk factors and nutrition behaviors in children. Overweight has increased, whereas saturated fat and cholesterol intake have decreased, at least as percentage of total caloric intake. Better understanding of children's cardiovascular risk status and current diet is available from national survey data. New research on the efficacy of diet intervention in children has been published. Also, increasing attention has been paid to the importance of nutrition early in life, including the fetal milieu. This scientific statement summarizes current available information on cardiovascular nutrition in children and makes recommendations for both primordial and primary prevention of cardiovascular disease beginning at a young age.

The role of dietary cations in the blood pressure of renal transplant recipients

BACKGROUND

The role of dietary cations in hypertension has been evaluated in the general population and selected subgroups, but its contribution to blood pressure (BP) elevations in patients with functional renal allografts has not been critically examined.

METHODS

After counseling based on Dietary Approaches to Stop Hypertension (DASH) guidelines, we measured timed 24-h urine excretion rates of sodium, potassium, calcium, and magnesium as a surrogate for their dietary intake, in 244 stable adult single-organ renal transplant recipients, correlating these with averaged blinded clinic-measured BP values. Multiple linear regression analysis adjusting for factors affecting BP in transplant recipients was performed.

RESULTS

There was no correlation between systolic (SBP) or diastolic pressure (DBP) and 24-h urine excretion rates of each cation. There was no BP difference between patients receiving cyclosporine and tacrolimus (127/77 vs. 129/78 mmHg, p = 0.38), or in cation excretion except for calcium (2.85 +/- 2.0 vs. 2.90 +/- 2.8, p = 0.002). Protein excretion (p < 0.0001), age (p = 0.002), and weight (p = 0.04) were positively associated with SBP, while only weight (p = 0.01) was associated with DBP by multivariate analysis.

CONCLUSION

Dietary cation intake is not significantly associated with BP in renal transplant recipients. These data do not support recommendations to alter dietary cation intake as part of the management of post-transplantation hypertension.

Early cardiovascular changes in 10- to 15-year-old stunted children: the Transition and Health during Urbanization in South Africa in Children study

OBJECTIVE

Early changes in vascular function could be associated with stunting, which may contribute to the development of cardiovascular diseases in later life. In this study we tested the hypothesis that stunting may be related to changes in cardiovascular function in African children ages 10 to 15 y.

METHODS

In the Transition and Health during Urbanization in South Africa in Children study, the health status of children in the North-West Province of South Africa was studied. It was an epidemiologic, cross-sectional study in which 583 black non-stunted and 192 stunted children (stature below the fifth percentile for age) of both sexes ages 10 to 15 y were recruited from 44 schools. Blood pressure was monitored with the Finapres (finger-arterial pressure) apparatus and by means of the Fast Modelflo software program; measurements for systolic and diastolic blood pressure, mean arterial pressure, pulse pressure, heart rate, cardiac output, stroke volume, total peripheral resistance, and arterial compliance were obtained. Dietary intake data were collected with a 24-h dietary recall questionnaire. Nutrient coding was the same for all recalls and macro- and micronutrients were calculated. Anthropometric measurements were done according to standard methods.

RESULTS

There were no significant differences in systolic blood pressure and diastolic blood pressure between stunted and non-stunted children after correction for body mass index and heart rate. Stroke volume, arterial compliance, and cardiac output were significantly lower and total peripheral resistance was significantly higher in stunted children than in non-stunted children. No significant differences in dietary intake could be detected, although dietary intakes were slightly lower in the stunted children.

CONCLUSIONS

We found that compliance, a marker of vascular function, is significantly lower in stunted children. Stunting was related to early changes in cardiovascular function in African children ages 10 to 15 y.

Treatment of dyslipidemia in children and adolescents

The early lesions of atherosclerosis begin in childhood, and are related to antecedent cardiovascular disease risk factors. Environmental and genetic factors such as diet, obesity, exercise, and certain inherited dyslipidemias influence the progression of such lesions. The identification of youth at risk for atherosclerosis includes an integrated assessment of these predisposing factors. Treatment starts with a diet low in total and saturated fat and cholesterol, the use of water-soluble fiber and plant sterols, weight control, and exercise. Drug therapy, for example, with inhibitors of hydroxymethylglutaryl CoA reductase, bile acid sequestrants, and cholesterol absorption inhibitors, can be considered in those with a positive family history of premature coronary artery disease and a low-density lipoprotein cholesterol above 160 mg/dL, after dietary and hygienic measures. Candidates for drug therapy often include those with familial hypercholesterolemia, familial combined hyperlipidemia, the metabolic syndrome, polycystic ovarian syndrome, type I diabetes, and the nephrotic syndrome. We review the safety and efficacy of dietary and drug therapy, and propose an updated diagnostic and therapeutic algorithm that includes the metabolic syndrome. The early identification and treatment of youth with dyslipidemias is likely to retard the atherosclerotic process.

Diet and blood pressure in children

PURPOSE OF REVIEW

The prevalence of hypertension among children in the US is increasing in concert with rising obesity rates. Leading health organizations agree that elevated blood pressure should be managed in children; however, data on the relation between diet and lifestyle and blood pressure in this age group are sparse and controversial. The purpose of this review is to summarize the current evidence regarding nutrients, foods, and dietary patterns and their role in blood pressure elevation and in the treatment of pediatric hypertension.

RECENT FINDINGS

There is clear evidence that avoidance of excess weight gain in early life is important for the prevention of future hypertension and that weight reduction is an important therapeutic intervention for the prevention and treatment of hypertension in overweight children. Similarly, reduction in dietary sodium may be beneficial for children who are salt sensitive, but this trait cannot be easily measured. Children who were breast-fed or consume a diet rich in fruits, vegetables, and dairy foods tend to have lower blood pressure in adolescence. How these foods lower blood pressure is unclear.

SUMMARY

Data supporting the efficacy of dietary interventions for preventing or treating high blood pressure are limited. Future studies should emphasize adequate sample size, adjustment for confounding factors, use of standardized blood pressure techniques, and random assignment of children in intervention trials. Additionally, because adherence to dietary interventions may be particularly problematic among children, innovative nutrition intervention approaches are needed that address the unique needs and circumstances of this age group.