Dietary protein intake and blood pressure: a meta-analysis of randomized controlled trials

Association between PEMT rs7946 and blood pressure levels in Chinese adolescents

OBJECTIVES

This study was to explore blood pressure levels in Chinese adolescents with different genotypes of phosphatidylethanolamine N-methyltransferase (PEMT) gene ( PEMT ) rs7946, as well as effects of dietary intake on blood pressure levels with different genders and different genotypes of PEMT rs7946.

METHODS

PEMT rs7946 genotypes were identified by PCR-restriction fragment length polymorphism and verified by DNA sequencing. Blood pressure was measured using a standard mercury sphygmomanometer. Dietary intakes were analyzed based on a 3-day diet diary, and dietary components were calculated using computer software.

RESULTS

A total of 721 high school students (314 males and 407 females) at the age of 16.86 ± 0.59 years were included. The A allele carriers of PEMT rs7946 had increased levels of SBP, DBP, mean arterial pressure (MAP) and pulse pressure (PP) than the GG homozygotes in the female subjects. There were significant interactions between PEMT rs7946 and gender on SBP and MAP levels, regardless of whether an unadjusted or adjusted model was used. When dietary intake was taken into account, fat intake was positively associated with SBP and PP in the male GG homozygotes, while protein intake was positively associated with PP in the female A allele carriers of PEMT rs7946.

CONCLUSION

This study suggests that PEMT rs7946 is significantly associated with blood pressure levels in human being. There might be interactions among PEMT rs7946, gender, and dietary intake on blood pressure levels in the adolescent population.

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.

Dietary amino acid profile and risk of hypertension: findings from the Ravansar cohort study

INTRODUCTION

Hypertension (HTN) is a significant global health concern associated with morbidity and mortality. Recent research has explored the potential relationship between dietary protein intake and the development of HTN. This study aims to investigate the association between dietary amino acids and the incidence of HTN.

METHODS

This nested case-control study utilized data from the Ravansar Non-Communicable Disease (RaNCD) Cohort Study. The study included 491 new HTN cases identified over a 6-year follow-up period. For each case, four controls were randomly selected through density sampling. A food frequency questionnaire (FFQ) consisting of 125 food items was used to calculate dietary amino acid intake. HTN was determined based on systolic blood pressure ≥ 140 mmHg and/or diastolic blood pressure ≥ 90 mmHg and/or current use of antihypertensive medication in subjects without pre-existing HTN at the start of the cohort study. Conditional logistic regression was used to estimate crude and adjusted odds ratios for HTN risk.

RESULTS

The median intake of all amino acids was lower in patients with HTN compared to the control group. After adjusting for various variables in different models, the risk of developing HTN tended to increase with higher dietary amino acid intake (excluding tryptophan and acidic amino acids). Specifically, individuals in the third tertile had a higher risk of developing new HTN than those individuals in the lowest tertile, although this difference was not statistically significant (P > 0.05).

CONCLUSION

The findings suggest that there may be an association between increased dietary amino acid intake and the risk of developing HTN, although this association was not statistically significant in this study. Further investigations in diverse populations are needed to explore the relationship between amino acids and HTN, as well as to determine the potential positive and negative effects of specific amino acid patterns on hypertension.

The Role of Diet in the Prevention of Hypertension and Management of Blood Pressure: An Umbrella Review of Meta-Analyses of Interventional and Observational Studies

High blood pressure (BP) is a major pathological risk factor for the development of several cardiovascular diseases. Diet is a key modifier of BP, but the underlying relationships are not clearly demonstrated. This is an umbrella review of published meta-analyses to critically evaluate the wide range of dietary evidence from bioactive compounds to dietary patterns on BP and risk of hypertension. PubMed, Embase, Web of Science, and Cochrane Central Register of Controlled Trials were searched from inception until October 31, 2021, for relevant meta-analyses of randomized controlled trials or meta-analyses of observational studies. A total of 175 publications reporting 341 meta-analyses of randomized controlled trials (145 publications) and 70 meta-analyses of observational studies (30 publications) were included in the review. The methodological quality of the included publications was assessed using Assessment of Multiple Systematic Reviews 2 and the evidence quality of each selected meta-analysis was assessed using NutriGrade. This umbrella review supports recommended public health guidelines for prevention and control of hypertension. Dietary patterns including the Dietary Approaches to Stop Hypertension and the Mediterranean-type diets that further restrict sodium, and moderate alcohol intake are advised. To produce high-quality evidence and substantiate strong recommendations, future research should address areas where the low quality of evidence was observed (for example, intake of dietary fiber, fish, egg, meat, dairy products, fruit juice, and nuts) and emphasize focus on dietary factors not yet conclusively investigated.

Dietary modification for prevention and control of high blood pressure

Hypertension (HT) remains the leading cause of cardiovascular and premature death around the world. Diet is one of the important factors that contributes to the development of HT. We review the current evidence of how different dietary factors may influence blood pressure (BP) and consequent development of HT. There is evidence that BP is positively associated with higher consumption of sodium, alcohol, animal-based protein such as red meat, low-quality carbohydrates such as sugar-sweetened beverages, and saturated fatty acids. On the contrary, other dietary constituents have BP-lowering effects. These include potassium, calcium, magnesium, yogurt, eggs, plant-based proteins such as soy and legumes, mono- and polyunsaturated fatty acids, and high-quality carbohydrates such as whole grain and fruits. Dietary fibre is unrelated to BP lowering, possibly due to the different mechanisms of various types of fibre. The effects of caffeine, hibiscus tea, pomegranate, and sesame on BP are also unclear as evidence is hard to assess due to the varying concentrations and different types of drinks used in studies. Implementing dietary changes such as the Dietary Approaches to Stop Hypertension (DASH diet) or adopting a Mediterranean diet has been shown to reduce and control BP. Although the effect of diet on BP control has been established, the optimal amount of each dietary component and consequent ability to devise a personalized diet for HT prevention and BP control for different populations still require further investigation.

Effects of minimally and ultra-processed foods on blood pressure in Brazilian adults: a two-year follow up of the CUME Project

AIM

To assess the association of food consumption according to degree of processing with changes in systolic (SBP) and diastolic (DBP) blood pressure in adult participants of a Brazilian cohort.

METHODS

Longitudinal study with 2496 adult participants of the Cohort of Universities of Minas Gerais (CUME Project). Food consumption was categorized by food groups according to degree of processing following the NOVA grading system: unprocessed/minimally processed foods/culinary ingredients (U/MPF&CI), processed foods (PFs) and ultra-processed foods (UPFs). unprocessed/minimally processed foods/culinary ingredients (U/MPF&CI), processed foods (PFs) and ultra-processed foods (UPFs). Changes in SBP and DBP were categorized (decreased, maintained, increased). Independent associations between exposure and outcomes were verified using multiple generalized ordered logistic models adjusted for potential confounders.

RESULTS

After a two-year follow-up, the consumption of U/MPF&CI (% daily caloric intake) reduced the chance of increasing DBP (P for trend = 0.014), with a more evident effect among participants within the 5th quintile of this food group (odds ratio (OR) = 0.55; 95% confidence interval (CI): 0.34-0.97]. On the other hand, the consumption of UPFs (% daily caloric intake) raised the chance of increasing DBP (P for trend = 0.005) and was more evident among participants within the quintiles of higher consumption (4th quintile - OR = 1.97; 95% CI: 1.25-3.10; 5th quintile - OR = 1.79; 95% CI = 1.12-2.86). No associations were found between food consumption according to degree of processing and changes in SBP.

CONCLUSION

Higher consumption of U/MPF&CI and UPFs were independently associated to lower and greater chances of increased DBP in adult participants from CUME Project.

Association between Macronutrient and Fatty Acid Consumption and Metabolic Syndrome: A South African Taxi Driver Survey

We aimed to examine the association between macronutrient and fatty acid intake and metabolic syndrome (MetS) and its components in South African male mini-bus taxi drivers. One hundred and eighty-five (n = 185) male taxi drivers, aged 20 years and older, who operate in the Cape Town metropole, South Africa, were included. The International Diabetes Federation (IDF) algorithm was used to define MetS. The association between macronutrient and fatty acid intake (assessed using 24 h recall) and MetS were analyzed using multivariable nutrient density substitution models. Overall, protein consumption significantly increased the likelihood of high blood pressure (HBP) and significantly lowered the likelihood of having low levels of high-density lipoprotein cholesterol (HDL-C). In an isoenergetic state, the intake of protein instead of carbohydrates (CHOs) and total fat, reduced the likelihood of elevated triglycerides by 6.7% and 6.6%, respectively. The intake of CHOs instead of protein and total fat, reduced the likelihood of HBP by 2.2% and 2.8%, respectively. In the same isoenergetic state, the intake of saturated fatty acids (SFAs) instead of mono-unsaturated fatty acids (MUFAs) increased the likelihood of HBP by 9.8%, whereas the intake of polyunsaturated fatty acids (PUFAs) instead of SFAs decreased the likelihood of HBP by 9.4%. The current study showed that when total food energy intake is kept constant, a diet that is high in protein, CHOs and PUFAs reduces triglycerides and BP, whereas the intake of total fat and SFAs had the opposite effect. It should, however, be noted that these outcomes were produced using mathematical models, as such we recommend further prospective studies in real life that will reveal the actual associations between the consumption of macronutrients and fatty acids and MetS and its components.

Effects of Cuisine-Based Chinese Heart-Healthy Diet in Lowering Blood Pressure Among Adults in China: Multicenter, Single-Blind, Randomized, Parallel Controlled Feeding Trial

BACKGROUND

More than one-fifth of the world's population consumes Chinese cuisines regularly, but no evidence-based healthy diets fitting the Chinese food culture are available for implementation.

METHODS

A multicenter, patient- and outcome assessor-blind, randomized feeding trial was conducted among 265 participants with 130 to 159 mm Hg baseline systolic blood pressure (SBP) for 4 major Chinese cuisines (Shangdong, Huaiyang, Cantonese, Szechuan). After a 7-day run-in period on a control diet matching the usual local diets, participants were randomized to continue with the control diet or the cuisine-based Chinese heart-healthy diet for another 28 days. The primary outcome was SBP, and secondary outcomes included diastolic blood pressure and food preference score. Linear regression models were used to estimate the intervention effects and adjustments for the center. The incremental cost per 1 mm Hg reduction in SBP was also calculated.

RESULTS

A total of 265 participants were randomized (135 on the Chinese heart-healthy diet and 130 on the control diet), with 52% women, mean age of 56.5±9.8 years, and mean SBP and diastolic blood pressure of 139.4±8.3 and 88.1±8.0 mm Hg, respectively, at baseline. The change in SBP and diastolic blood pressure from baseline to the end of the study in the control group was -5.0 (95% CI, -6.5 to -3.5) mm Hg and -2.8 (95% CI, -3.7 to -1.9) mm Hg, respectively. The net difference of change between the 2 groups in SBP and diastolic blood pressure were -10.0 (95% CI, -12.1 to -7.9) mm Hg and -3.8 (95% CI, -5.0 to -2.5) mm Hg, respectively. The effect size did not differ among cuisines (P for interaction=0.173). The mean food preference score was 9.5 (with 10 the best preferred) at baseline, and the net change during intervention was 0.1 (95% CI, -0.1 to 0.2; P=0.558). The incremental cost-effectiveness ratio per 1 mm Hg SBP reduction was CNY 0.4 (USD 0.06) per day. No difference in the number of adverse events was found between the 2 groups (P=0.259), and none of the adverse events was associated with the intervention.

CONCLUSIONS

The Chinese heart-healthy diet is effective, palatable, and cost-effective in reducing blood pressure in Chinese adults with high blood pressure, with a clinically significant effect applicable across major Chinese cuisine cultures.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT03882645.

Soy isoflavones plus soy protein effects on serum concentration of leptin in adults: A systematic review and meta-analysis of randomized clinical trials

BACKGROUND

Some studies conducted on soy isoflavones and soy protein reflected that leptin can be reduced by soy isoflavones or soy protein. The aim of present study is to assess the effect of soy isoflavones plus soy protein on serum concentration of leptin among adults.

METHODS

To find randomized clinical trails (RCTs) assessing the effect of soy isoflavones containing soy protein on serum concentration of leptin in participants with age ≥18 years old, databases including PubMed, Scopus, ISI Web of Science, Cochrane and ClinicalTrials.gov were searched up to March 2021. We calculated the effect size by the mean change from baseline of leptin concentrations and its standard deviation for intervention and comparison groups. DerSimonian and Laird random effects model was used to estimate the overall summary effect and the heterogeneity. Risk of bias was conducted by Cochrane Collaboration's tool. Study protocol was registered in PROSPERO (No. CRD42021228366).

RESULTS

Eight articles with 421 participants and six articles with 336 participants were known to be eligible for systematic review and meta-analysis, respectively. A pooled analysis revealed that the combination of soy isoflavones and soy protein had a borderline non-significant on serum concentration of leptin (weighted mean difference (WMD): -1.03 ng/ml, 95% confidence interval (CI): -2.11, 0.05 ng/ml). This combination reduced serum leptin levels in studies with baseline levels of leptin ≤22 ng/ml, in short-term trials (≤56 days), studies that used soy isoflavones with dose ≤96 mg/day and among subjects with health risk factors or diseases.

CONCLUSION

Soy isoflavones plus soy protein had a non-significant decreasing effect on the serum concentration of leptin. However, making firm conclusion needs more studies on participants with different health condition, and different soy isoflavones doses and intervention duration.

Inverse Association Between Variety of Proteins With Appropriate Quantity From Different Food Sources and New-Onset Hypertension

The relationships of the variety and quantity of different sources of dietary proteins with hypertension remain uncertain. We aimed to investigate associations between the variety and quantity of proteins intake from 8 major food sources and new-onset hypertension among 12 177 participants from the China Health and Nutrition Survey. Dietary intake was measured by 3 consecutive 24-hour dietary recalls combined with a household food inventory. The variety score of protein sources was defined as the number of protein sources consumed at the appropriate level, accounting for types and quantity of proteins. New-onset hypertension was defined as systolic blood pressure ≥140 mm Hg and diastolic blood pressure ≥90 mm Hg, or physician-diagnosed hypertension or receiving antihypertensive treatment, during the follow-up. During a median follow-up of 6.1 years, there were U-shaped associations of percentages energy from total, unprocessed or processed red meat-derived, whole grain-derived, and poultry-derived proteins with new-onset hypertension; an reverse J-shaped association of fish-derived protein with new-onset hypertension; L-shaped associations of eggs-derived and legumes-derived proteins with new-onset hypertension; and an reverse L-shaped association of refined grain-derived protein with new-onset hypertension (all P values for nonlinearity <0.001). That is, for each protein, there is a window of consumption (appropriate level) where the risk of hypertension is lower. Moreover, a significantly lower risk of new-onset hypertension was found in those with higher variety score of protein sources (per score increment, hazard ratio, 0.74 [95% CI, 0.72-0.76]). In summary, there was an inverse association between the variety of proteins with appropriate quantity from different food sources and new-onset hypertension.

Supplementation of amino acids and organic acids prevents the increase in blood pressure induced by high salt in Dahl salt-sensitive rats

A high-salt (HS) diet leads to metabolic disorders in Dahl salt-sensitive (SS) rats, and promotes the development of hypertension. According to the changes in the metabolites of SS rats, a set of combined dietary supplements containing amino acids and organic acids (AO) were designed. The purpose of the present study was to evaluate the effect of AO supplementation on the blood pressure of SS rats after the HS diet and clarify the mechanism of AO by metabolomics and biochemical analyses. The results showed that AO supplementation avoided the elevation of blood pressure induced by the HS diet in SS rats, increased the renal antioxidant enzyme activities (catalase, superoxide dismutase, glutathione reductase, and glutathione S-transferase), reduced the H₂O₂ and MDA levels, and restored the normal antioxidant status of the serum and kidneys. AO also reversed the decrease in the nitric oxide (NO) levels and NO synthase activity induced by the HS feed, which involved the L-arginine/NO pathway. Metabolomics analysis showed that AO administration increased the levels of amino acids such as cysteine, glycine, hypotaurine, and lysine in the renal medulla and the levels of leucine, isoleucine, and serine in the renal cortex. Of note, lysine, hypotaurine and glycine had higher metabolic centrality in the metabolic correlation network of the renal medulla after AO administration. In conclusion, AO intervention could prevent HS diet-induced hypertension in SS rats by restoring the metabolic homeostasis of the kidneys. Hence, AO has the potential to become a functional food additive to improve salt-sensitive hypertension.

Relations of Variety and Quantity of Dietary Proteins Intake from Different Sources with Mortality Risk: A Nationwide Population-Based Cohort

OBJECTIVES

The relations of variety and quantity of dietary proteins intake from different sources with mortality risk were still controversial. We aimed to examine the associations of variety and quantity of different sourced proteins with all-cause mortality risk in adults and older adults.

MATERIALS AND METHODS

17,310 participants (mean age was 44.0 [SD: 15.9] years and 51.0% were females) with utilizable data from the China Health and Nutrition Survey were included. Dietary intake was collected using three consecutive 24-h dietary recalls combined with a household food inventory. The variety score of protein sources was defined as the number of proteins consumed at the appropriate level, accounting for both types and quantity of proteins. The primary outcome was all-cause mortality.

RESULTS

Over a median follow-up of 9.0 years, 1324 (7.6%) death cases were reported. There were reversed J-shaped relationships of percentages energy from total protein, and protein from legume with all-cause mortality; U-shaped relationships of proteins from unprocessed red meat, processed red meat, poultry and whole grain with all-cause mortality; L-shaped relationships of proteins from egg and fish with all-cause mortality; and a reversed L-shaped relationship of protein from refined grain with all-cause mortality (all P values for nonlinearity < 0.001). Moreover, there was a significant inverse association between the variety score of protein sources with overall mortality risk (per score increment, HR, 0.69; 95%CI, 0.66-0.72).

CONCLUSIONS

Greater variety of proteins with appropriate quantity from different food sources was associated with significantly lower risk of mortality in Chinese adults and older adults.

Biological Functions and Activities of Rice Bran as a Functional Ingredient: A Review

Rice bran (RB) is a nutrient-rich by-product of the rice milling process. It consists of pericarp, seed coat, nucellus, and aleurone layer. RB is a rich source of a protein, fat, dietary fibers, vitamins, minerals, and phytochemicals (mainly oryzanols and tocopherols), and is currently mostly used as animal feed. Various studies have revealed the beneficial health effects of RB, which result from its functional components including dietary fiber, rice bran protein, and gamma-oryzanol. The health effects of RB including antidiabetic, lipid-lowering, hypotensive, antioxidant, and anti-inflammatory effects, while its consumption also improves bowel function. These health benefits have drawn increasing attention to RB in food applications and as a nutraceutical product to mitigate metabolic risk factors in humans. This review therefore focuses on RB and its health benefits.

Dietary Animal to Plant Protein Ratio Is Associated with Risk Factors of Metabolic Syndrome in Participants of the AHS-2 Calibration Study

BACKGROUND

Few research studies have focused on the effects of dietary protein on metabolic syndrome and its components. Our objective was to determine the relationship between the type of dietary protein intake and animal to plant (AP) protein ratio with metabolic syndrome and its components.

METHODS

This population-based study had a cross sectional design and conducted on 518 participants of the Adventist Health Study 2 (AHS-2) Calibration Study. Two sets of three dietary 24-h recalls were obtained six months apart. Anthropometric measures and biochemical tests were performed in clinics. Regression calibration models were used to determine the association of type of dietary protein with metabolic syndrome and its components (raised triglyceride, raised blood pressure, reduced high-density lipoprotein cholesterol (HDL), raised fasting blood glucose and increased waist circumference).

RESULTS

The likelihood of metabolic syndrome was lower in those with higher total dietary protein and animal protein intake (p = 0.02).Total protein (β = 0.004, [95%CI: 0.002, 0.007]), animal protein intake (β = 0.004, [95%CI: 0.001, 0.007]) and AP protein intake ratio (β = 0.034, [95%CI: 0.021, 0.047]) were positively associated with waist circumference. Higher AP protein ratio was related to higher fasting blood glucose (β = 0.023, [95%CI: 0.005, 0.041]).

CONCLUSION

Our study suggests that considering a significant amount of plant protein as a part of total dietary protein has beneficial effects on cardiometabolic risk factors.

The long-term association of different dietary protein sources with metabolic syndrome

Due to scarce epidemiologic data linking dietary protein intakes and metabolic syndrome (MetS), we aim to determine the longitudinal association of different types of dietary protein with the incidence of MetS among Iranians adults. The study was conducted in the framework of the Isfahan Cohort Study (ICS) on 6504 adults, aged ≥ 35 years, and free of MetS at baseline. A validated food frequency questionnaire was used for assessing usual dietary intakes. MetS was defined according to the Joint Scientific Statement. Mixed-effects logistic regression was applied to examine the associations between changes in weekly frequency consumption of protein and MetS status. After a median follow-up of 11.25 years, in multivariate-adjusted model, each additional frequency consumption of total protein intake (OR 0.83; 95% CI 0.81–0.85), animal protein (OR 0.80; 95% CI 0.77–0.83), plant protein (OR 0.70; 95% CI 0.64–0.76), red meat (OR 0.74; 95% CI 0.70–0.78), poultry (OR 0.73; 95% CI 0.68–0.78), egg (OR 0.79; 95% CI 0.72–0.88) and nuts and seeds (OR 0.77; 95% CI 0.71–0.84) was associated with reduced risk of MetS. No significant association was found for processed meat (OR 0.96; 95% CI 0.87–1.01) and legumes and soy (OR 0.96; 95% CI 0.86–1.07) with MetS. Our results suggest an independent inverse association between total protein, animal and plant protein and the risk of MetS. These associations did not differ by sex. Although our results can be considered to be a strategy to reduce MetS risk by dietary guidelines, randomized clinical trials are required to confirm our findings.

Social integration after moving to a new city predicts lower systolic blood pressure

Residential mobility is linked to higher incidence of cardiovascular disease (CVD) and mortality. A mechanism by which residential relocation may impact health is through the disruption of social networks. To examine whether moving to a new city is associated with increased CVD risk and whether the extent to which movers rebuild their social network after relocating predicts improved CVD risk and psychosocial well-being, recent movers (n = 26), and age- and sex-matched nonmovers (n = 20) were followed over 3 months. Blood pressure, C-reactive protein/albumin ratio (CRP/ALB), social network size, and psychosocial well-being were measured at intake (within 6 weeks of residential relocation for movers) and 3 months later. Multiple regression indicated higher systolic blood pressure (SBP) for movers (M = 107.42, SD = 11.39), compared with nonmovers (M = 102.37, SD = 10.03) at intake, though this trend was not statistically significant. As predicted, increases in movers' social network size over 3 months predicted decreases in SBP, even after controlling for age, sex, and waist-to-hip ratio, b = -2.04 mmHg, 95% CI [-3.35, -.73]. Associations between increases in movers' social ties and decreases in depressive symptoms and stress were in the predicted direction but did not meet the traditional cutoff for statistical significance. Residential relocation and movers' social network size were not associated with CRP/ALB in this healthy sample. This study provides preliminary evidence for increased SBP among recent movers; furthermore, it suggests that this elevation in CVD risk may decrease as individuals successfully rebuild their social network.

Associations of choline intake with hypertension and blood pressure among older adults in cross-sectional 2011-2014 National Health and Nutrition Examination Survey (NHANES) differ by BMI and comorbidity status

Blood pressure (BP) is a known cardiovascular risk factor that is hypothesised to be inversely related to choline intake. A previous study suggested that this association may be more apparent in older adults and may differ according to demographic and health characteristics. The primary study objectives are to investigate the cross-sectional associations of total choline intake with BP (n 843) and prevalent hypertension (n 2113) among USA adults aged ≥ 65 years using the sample from the 2011 to 2014 National Health and Nutrition Examination Survey. Logistic and multiple linear regression models for complex surveys were employed for hypertension status and BP, respectively. Effect modification by sex, race, BMI and comorbidity status were separately investigated using an interaction term. Choline intake interacted with BMI (P-interaction = 0·04) such that choline intake tended to be associated with lower odds of hypertension among people with BMI < 18·5 kg/m2 (OR (95 % CI): 0·64 (0·4, 1·00); P = 0·052). Choline intake was not associated with systolic BP (mean ± sem change per 100 mg of choline: -1·03 ± 0·74 mmHg; P = 0·16). In contrast, its relation to diastolic BP differed by cardiovascular comorbidity (P-interaction = 0·03) with a non-significant (P = 0·13) negative direction of association observed among those who were free of comorbidities and a non-significant (P = 0·26) positive direction observed among those with comorbidities. Collectively, these results suggested that the associations of choline intake with BP levels and hypertension risk among older adults are dependent on other risk factors.

Tropical foods as functional foods for metabolic syndrome

Tropical foods are an integral part of the traditional diet and form part of traditional medicine in many countries. This review examines the potential of tropical foods to treat signs of metabolic syndrome, defined as a chronic low-grade inflammation leading to obesity, hypertension, impaired glucose tolerance, insulin resistance, dyslipidaemia and fatty liver. It is a major risk factor for cardiovascular and metabolic disease as well as osteoarthritis and some cancers. Tropical foods such as seaweeds and tropical fruits including indigenous fruits such as Davidson's plums are effective in reducing these signs of metabolic syndrome in rats, as well as reducing degeneration of bone cartilage and altering gut microbiome. Further, waste products from tropical fruits including mangosteen rind, coffee pulp and spent coffee grounds provide further options to reduce metabolic syndrome. Production of local tropical foods and local recovery of food waste from these foods could allow the development of commercial, sustainable and cost-effective functional foods in tropical countries. The aim is to develop these functional foods to reduce the incidence of metabolic syndrome and decrease the risk of costly chronic cardiovascular and metabolic disorders locally and globally.

Nutraceuticals and blood pressure control: a European Society of Hypertension position document

: High-normal blood pressure (BP) is associated with an increased risk of cardiovascular disease, however the cost-benefit ratio of the use of antihypertensive treatment in these patients is not yet clear. Some dietary components and natural products seems to be able to significantly lower BP without significant side effects. The aim of this position document is to highlight which of these products have the most clinically significant antihypertensive action and wheter they could be suggested to patients with high-normal BP. Among foods, beetroot juice has the most covincing evidence of antihypertensive effect. Antioxidant-rich beverages (teas, coffee) could be considered. Among nutrients, magnesium, potassium and vitamin C supplements could improve BP. Among nonnutrient-nutraceuticals, soy isoflavones could be suggested in perimenopausal women, resveratrol in insulin-resistant patients, melatonin in study participants with night hypertension. In any case, the nutracutical approach has never to substitute the drug treatment, when needed.

Association Between Blood Pressure and Branched-Chain/Aromatic Amino Acid Excretion Rate in 24-Hour Urine Samples from Elderly Hypertension Patients

BACKGROUND

Recently, the association between lifestyle-related diseases and free amino acids in the blood plasma-especially branched-chain amino acids (BCAAs) and aromatic amino acids (AAAs)-has been highlighted. However, few studies have been carried out on 24-hour urine samples. Therefore, we aimed to explore the relationships between 24-hour urinary BCAAs and AAAs excretion rate and blood pressure (BP) in elderly patients with hypertension.

METHODS AND RESULTS

Each of the 322 elderly patients with hypertension completed an in-person questionnaire interview, underwent a physical examination, and provided a 24-hour urine specimen. We measured their BCAAs and AAAs excretion rate, and used multiple linear regression analysis with variable selection to construct models describing the relationships between their BCAAs and AAAs excretion rate and BP. After adjusted for age, gender, height, and weight, valine was inversely associated with both systolic blood pressure (SBP) (β: -0.232, 95% CI: -0.16, -0.006) and diastolic blood pressure (DBP) (β: -0.144, 95% CI: -0.089, -0.005). These findings were invariant even following adjustment for urine volume and drugs history, and Ile was positively associated with DBP (β: 0.170, 95% CI: 0.001, 0.066).

CONCLUSION

The data revealed that the excretion rate of 24-hour urinary BCAAs was closely related to BP in elderly hypertension patients, and these findings will provide new insights into the association between BACC metabolism and BP.

Efficacy of different dietary patterns on lowering of blood pressure level: an umbrella review

BACKGROUND

Many systematic reviews and meta-analyses have assessed the efficacy of dietary patterns on blood pressure (BP) lowering but their findings are largely conflicting.

OBJECTIVE

This umbrella review aims to provide an update on the available evidence for the efficacy of different dietary patterns on BP lowering.

METHODS

PubMed and Scopus databases were searched to identify relevant studies through to June 2020. Systematic reviews with meta-analyses of randomized controlled trials (RCTs) were eligible if they measured the effect of dietary patterns on systolic (SBP) and/or diastolic blood pressure (DBP) levels. The methodological quality of included systematic reviews was assessed by A Measurement Tool to Assess Systematic Review version 2. The efficacy of each dietary pattern was summarized qualitatively. The confidence of the effect estimates for each dietary pattern was graded using the NutriGrade scoring system.

RESULTS

Fifty systematic reviews and meta-analyses of RCTs were eligible for review. Twelve dietary patterns namely the Dietary Approaches to Stop Hypertension (DASH), Mediterranean, Nordic, vegetarian, low-salt, low-carbohydrate, low-fat, high-protein, low glycemic index, portfolio, pulse, and Paleolithic diets were included in this umbrella review. Among these dietary patterns, the DASH diet was associated with the greatest overall reduction in BP with unstandardized mean differences ranging from -3.20 to -7.62 mmHg for SBP and from -2.50 to -4.22 mmHg for DBP. Adherence to Nordic, portfolio, and low-salt diets also significantly decreased SBP and DBP levels. In contrast, evidence for the efficacy of BP lowering using the Mediterranean, vegetarian, Paleolithic, low-carbohydrate, low glycemic index, high-protein, and low-fat diets was inconsistent.

CONCLUSION

Adherence to the DASH, Nordic, and portfolio diets effectively reduced BP. Low-salt diets significantly decreased BP levels in normotensive Afro-Caribbean people and in hypertensive patients of all ethnic origins. This review was registered at PROSPERO as CRD42018104733.

Consumption of animal and plant foods and risk of left ventricular diastolic dysfunction: the Bogalusa Heart Study

AIMS

Left ventricular diastolic dysfunction (LVDD) is an early heart failure with preserved ejection fraction (HFpEF) phenotype that is reversible. Identifying dietary predictors associated with LVDD in diverse populations may help broadly improve HFpEF primary prevention.

METHODS AND RESULTS

This longitudinal analysis included 456 individuals of the Bogalusa Heart Study (27% Black, 63% women, baseline age = 36.1 ± 4.4 years). Diet was measured at baseline through food frequency questionnaires. LVDD was defined at follow-up (median = 12.9 years) through echocardiographic measurement of the E/A ratio, E/e' ratio, isovolumic relaxation time, and deceleration time. Multivariable-adjusted logistic regression estimated the risk of LVDD according to dietary predictor, adjusting for traditional cardiovascular disease risk factors. Compared with the lowest tertile, participants in the middle tertile of total protein (OR = 3.30, 95% CI: 1.46, 7.45) and animal protein (OR = 2.91, 95% CI: 1.34, 6.34) consumption experienced the highest risk of LVDD. There was a 77% and 56% lower risk of LVDD for persons in the middle vs. lowest tertile of vegetable (OR = 0.23, 95% CI: 0.11, 0.49) and legume consumption (OR = 0.44, 95% CI: 0.22, 0.85), respectively. Total protein, animal protein, processed meat, and egg consumption indicated a quadratic trend towards increased risk of LVDD, while legume and vegetable intake conferred a quadratic trend towards decreased risk of LVDD (all quadratic P < 0.05).

CONCLUSIONS

Diets higher in animal foods and lower in plant foods are associated with an increased risk for LVDD. These findings suggest threshold effects of diet on LVDD, past which more traditional cardiometabolic determinants occupy a larger role in HFpEF risk.

A high-protein meal does not improve blood pressure or vasoactive biomarker responses to acute exercise in humans

Blood pressure (BP) responses to exercise yield prognostic information beyond resting BP. While habitual higher dietary protein intake is associated with reduced resting BP, few studies have assessed the impact of high-protein meals on acute BP and vasoactive biomarker responses to exercise. To test the hypothesis that consuming a higher-protein, lower fat meal (HP; 30 g protein, 17 g fat, 52 g carbohydrate) would attenuate the BP response to exercise and result in a more robust post-exercise hypotensive response compared to a lower-protein, higher-fat meal (LP; 13 g protein, 25 g fat, 54 g carbohydrate), we recruited 31 pre-hypertensive subjects to complete this randomized, double-blind, cross-over acute feeding study. One hundred sixty-five minutes after consuming the test HP or LP meal, subjects exercised on a cycle ergometer at 70% VO₂ max for 30 minutes. Blood pressure was measured prior to the meal and periodically before, during, and after exercise for a 315-minute period. Blood samples were periodically collected to quantify plasma arginine, arginine metabolites (asymmetric dimethylarginine, symmetric dimethylarginine; ADMA, SDMA), endothelin-1, nitrates, and nitrites in a subset of subjects (n = 15) as shown in Supplemental Table S1. Consuming the HP meal did not influence the BP responses to exercise, including the post-exercise return to baseline BP or systolic BP area under the curve. While the HP meal resulted in greater postprandial plasma arginine concentrations, ADMA, SDMA, endothelin-1, nitrates, and nitrites were unaltered. These results suggest that consuming a higher-protein, lower-fat meal does not influence BP or vasoactive biomarker responses to exercise compared to a lower-protein, higher-fat meal.

Association Between Plant and Animal Protein Intake and Overall and Cause-Specific Mortality

IMPORTANCE

Although emphasis has recently been placed on the importance of high-protein diets to overall health, a comprehensive analysis of long-term cause-specific mortality in association with the intake of plant protein and animal protein has not been reported.

OBJECTIVE

To examine the associations between overall mortality and cause-specific mortality and plant protein intake.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study analyzed data from 416 104 men and women in the US National Institutes of Health-AARP Diet and Health Study from 1995 to 2011. Data were analyzed from October 2018 through April 2020.

EXPOSURES

Validated baseline food frequency questionnaire dietary information, including intake of plant protein and animal protein.

MAIN OUTCOMES AND MEASURES

Hazard ratios and 16-year absolute risk differences for overall mortality and cause-specific mortality.

RESULTS

The final analytic cohort included 237 036 men (57%) and 179 068 women. Their overall median (SD) ages were 62.2 (5.4) years for men and 62.0 (5.4) years for women. Based on 6 009 748 person-years of observation, 77 614 deaths (18.7%; 49 297 men and 28 317 women) were analyzed. Adjusting for several important clinical and other risk factors, greater dietary plant protein intake was associated with reduced overall mortality in both sexes (hazard ratio per 1 SD was 0.95 [95% CI, 0.94-0.97] for men and 0.95 [95% CI, 0.93-0.96] for women; adjusted absolute risk difference per 1 SD was -0.36% [95% CI, -0.48% to -0.25%] for men and -0.33% [95% CI, -0.48% to -0.21%] for women; hazard ratio per 10 g/1000 kcal was 0.88 [95% CI, 0.84-0.91] for men and 0.86 [95% CI, 0.82-0.90] for women; adjusted absolute risk difference per 10 g/1000 kcal was -0.95% [95% CI, -1.3% to -0.68%] for men and -0.86% [95% CI, -1.3% to -0.55%] for women; all P < .001). The association between plant protein intake and overall mortality was similar across the subgroups of smoking status, diabetes, fruit consumption, vitamin supplement use, and self-reported health status. Replacement of 3% energy from animal protein with plant protein was inversely associated with overall mortality (risk decreased 10% in both men and women) and cardiovascular disease mortality (11% lower risk in men and 12% lower risk in women). In particular, the lower overall mortality was attributable primarily to substitution of plant protein for egg protein (24% lower risk in men and 21% lower risk in women) and red meat protein (13% lower risk in men and 15% lower risk in women).

CONCLUSIONS AND RELEVANCE

In this large prospective cohort, higher plant protein intake was associated with small reductions in risk of overall and cardiovascular disease mortality. Our findings provide evidence that dietary modification in choice of protein sources may influence health and longevity.

Moderate Intake of Lean Red Meat was Associated with Lower Risk of Elevated Blood Pressure in Chinese Women: Results from the China Health and Nutrition Survey, 1991-2015

This study aimed to examine longitudinal associations between fatty and lean, fresh red meat intake and blood pressure (BP) in Chinese adults. The data were from nine waves of the China Health and Nutrition Survey (1991–2015), a longitudinal, open cohort study. The surveys were conducted in 303 urban and rural communities of 15 provinces in China. Collected by consecutive three-day 24-h dietary recalls combined with household weighing for foods or only condiments, the diet exposure of interest was daily red meat intake and its subtypes (fatty versus lean) defined by 10-g fat content per 100 g. The main outcome was systolic blood pressure (SBP), diastolic blood pressure (DBP) and risk of elevated BP defined as having a mean of SBP ≥ 135 mmHg, DBP ≥ 85 mmHg, or taking antihypertensive medication. Three-level mixed-effect regressions showed women had SBP increases of 2.19 mmHg (95% CI: 1.07, 4.46) from a higher intake of total fresh red meat, 2.42 mmHg (95% CI: 1.18, 4.94) from a higher intake of fatty, fresh red meat, as well as 0.48 mmHg (95% CI: 0.26, 0.88) from a higher intake of lean, fresh red meat in the top tertile versus bottom one when adjusted for potential confounders. After adjusting for survey years, women with the highest tertile of lean, fresh red meat intake had a 32% lower risk of elevated BP (OR 0.68, 95%CI:0.48, 0.96) as compared with those with the first tertile (non-consumer). Fatty and lean, fresh red meat intakes were differentially associated with BP among Chinese adults. Further research is required to elicit the potential mechanism on gender-specific differential association of fatty versus lean, fresh red meat with BP.

A double-blind, randomized, crossover trial protocol of whole hemp seed protein and hemp seed protein hydrolysate consumption for hypertension

BACKGROUND

Primary hypertension accounts for almost 95% of all cases of high blood pressure and is a major modifiable risk factor for cardiovascular diseases. Lifestyle interventions have been shown to prevent hypertension. One of the prominent potential therapeutic lifestyle strategies to prevent or manage hypertension is increasing dietary protein as a macronutrient or as bioactive peptides. An emerging plant-based protein source that may have anti-hypertensive properties is hemp seed.

METHODS/DESIGN

A randomized, double-blind, crossover clinical trial will be conducted on 35 hypertensive participants aged 18-75 years, with a BMI between 18.5 and 40 kg/m², systolic blood pressure (SBP) between 130 and 160 mmHg and diastolic blood pressure (DBP) ≤ 110 mmHg. The trial will be conducted for a period of 22 weeks and will consist of three treatment periods of 6 weeks, separated by 2-week washout periods. The treatments will be consumed twice a day and consist of 25 g casein, hemp seed protein (HSP), or HSP plus HSP hydrolysate (HSP+). The primary outcome of this trial is 24-h SBP, measured on the first day of first phase and the last day of each phase. Office-measured blood pressure, pulse-wave velocity and augmentation index and anthropometrics will be determined at the first and last days of each period. Also, body composition will be assessed by dual x-ray absorptiometry (DXA) scan on the first day of the first phase and within the last 2 days of each treatment period. Blood samples will be collected on the first and last 2 days of each treatment phase whereas urine samples will be collected on the first day of the first phase plus the last day of each phase to be analyzed for specific biomarkers.

DISCUSSION

This trial protocol is designed to evaluate the hypotensive potential of consuming whole HSP, and HSP+, in comparison to casein protein. This study will be the first trial investigating the potential anti-hypertensive benefit of dietary hemp protein plus bioactive peptide consumption in humans.

TRIAL REGISTRATION

National Clinical Trial (NCT), ID: NCT03508895. Registered on 28 June 2018. Retrospectively registered on the publicly accessible Registry Databank at ClinicalTrials.gov (http://ClinicalTrials.gov).

Operational Differences in Plant-Based Diet Indices Affect the Ability to Detect Associations with Incident Hypertension in Middle-Aged US Adults

BACKGROUND

Several distinct plant-based diet indices (PDIs) have been developed to characterize adherence to plant-based diets.

OBJECTIVE

We contrasted 5 PDIs in a community-based cohort by assessing characteristics of the diet and evaluating whether these PDIs are associated with risk of incident hypertension.

METHODS

Using FFQ data from adults (45-64 y, n = 8041) without hypertension at baseline in the Atherosclerosis Risk in Communities (ARIC) Study, we scored participants' diets using the overall PDI (oPDI), healthy PDI (hPDI), less healthy (unhealthy) PDI (uPDI), provegetarian diet index, and PDI from the Rotterdam Study (PDI-Rotterdam). For the oPDI, provegetarian diet, and PDI-Rotterdam, higher intakes of all or selected plant foods received higher scores. For the hPDI, higher intakes of plant foods identified as healthful received higher scores. For the uPDI, higher intakes of less healthy plant foods received higher scores. All indices scored higher intakes of animal foods lower. We examined agreement between indices, and whether scores on these indices were associated with risk of hypertension using Cox proportional hazard models.

RESULTS

The PDIs were moderately-to-strongly correlated and largely ranked subjects consistently, except for the uPDI. Over a median follow-up of 13 y, 6044 incident hypertension cases occurred. When adjusted for sociodemographic characteristics, other dietary factors, and health behaviors, the highest compared with the lowest quintile for adherence to the oPDI, hPDI, and provegetarian diet was associated with a 12-16% lower risk of hypertension (all P-trend <0.05). Highest adherence to the uPDI was associated with a 13% higher risk of hypertension, when clinical factors were further adjusted for (P-trend = 0.03). No significant association was observed with the PDI-Rotterdam. The oPDI, hPDI, and provegetarian diet moderately improved the prediction of hypertension.

CONCLUSIONS

In middle-aged US adults, despite moderate agreement in ranking subjects across PDIs, operational differences can affect the ability to detect diet-disease associations, such as hypertension.

The global epidemiology of hypertension

Hypertension is the leading cause of cardiovascular disease and premature death worldwide. Owing to the widespread use of antihypertensive medications, global mean blood pressure (BP) has remained constant or has decreased slightly over the past four decades. By contrast, the prevalence of hypertension has increased, especially in low- and middle-income countries (LMICs). Estimates suggest that 31.1% of adults (1.39 billion) worldwide had hypertension in 2010. The prevalence of hypertension among adults was higher in LMICs (31.5%, 1.04 billion people) than in high-income countries (28.5%, 349 million people). Variations in the levels of risk factors for hypertension, such as high sodium intake, low potassium intake, obesity, alcohol consumption, physical inactivity and unhealthy diet, may explain some of the regional heterogeneity in hypertension prevalence. Despite the increasing prevalence, the proportions of hypertension awareness, treatment and BP control are low, particularly in LMICs, and few comprehensive assessments of the economic impact of hypertension exist. Future studies are warranted to test implementation strategies for hypertension prevention and control, especially in low-income populations, and to accurately assess the prevalence and financial burden of hypertension worldwide.

Vegetarian diets and chronic kidney disease

While dietary restriction of protein intake has long been proposed as a possible kidney-protective treatment, the effects of changes in the quality of ingested proteins on the prevalence and risk of progression of chronic kidney disease (CKD) have been scarcely studied; these two aspects are reviewed in the present article. The prevalence of hypertension, type 2 diabetes and metabolic syndrome, which are the main causes of CKD in Western countries, is lower in vegetarian populations. Moreover, there is a negative relationship between several components of plant-based diets and numerous factors related to CKD progression such as uraemic toxins, inflammation, oxidative stress, metabolic acidosis, phosphate load and insulin resistance. In fact, results from different studies seem to confirm a kidney-protective effect of plant-based diets in the primary prevention of CKD and the secondary prevention of CKD progression. Various studies have determined the nutritional safety of plant-based diets in CKD patients, despite the combination of a more or less severe dietary protein restriction. As observed in the healthy population, this dietary pattern is associated with a reduced risk of all-cause mortality in CKD patients. We propose that plant-based diets should be included as part of the clinical recommendations for both the prevention and management of CKD.

Adherence to the Dietary Approaches to Stop Hypertension (DASH) and hypertension risk: results of the Longitudinal Study of Adult Health (ELSA-Brasil)

We investigated whether high adherence to the Dietary Approaches to Stop Hypertension (DASH) diet was independently associated with lower risk of incident hypertension. Participants included 5632 adults, without hypertension at the baseline (2008-2010) of the Longitudinal Study of Adult Health, who took part in the second follow-up visit (2012-2014). Adherence to the DASH diet was estimated at baseline using a score based on eight food items (final scores from 8 to 40 points) and was categorised as high adherence (≥30 points, or ≥75 %) and low adherence (<75 %; reference). Hypertension was defined as systolic blood pressure (BP) ≥140 mmHg or diastolic BP ≥90 mmHg, or use of antihypertensive drugs. The association between adherence to the DASH diet and the risk of incident hypertension was estimated using Cox regression models adjusted by covariates. In total, 780 new cases of hypertension (13·8 %) were identified in about 3·8-year follow-up. Participants with high adherence to the DASH diet had 26 % lower risk of hypertension (hazard ratio (HR) 0·74; 95 % CI 0·57, 0·95) after adjustment for socio-demographic characteristics, health-related behaviours, diabetes and family history of hypertension. The HR reduced to 0·81 (95 % CI 0·63, 1·04) and was of borderline statistical significance after adjustment for BMI, suggesting that lower body weight explains about 10 % of the association between high adherence to the DASH diet and hypertension risk reduction. The results indicate that high adherence to the DASH diet lowered the risk of hypertension by one-fourth over a relatively short follow-up period.

The effect of regular consumption of lupin-containing foods on glycaemic control and blood pressure in people with type 2 diabetes mellitus

Type 2 diabetes mellitus is a metabolic disorder characterized by high glucose and insulin resistance.

Identification of Dietary Patterns Related to Metabolic Diseases and Their Association with Cardiovascular Disease: From the Korean Genome and Epidemiology Study

Using data from the community-based cohort of the Korean Genome and Epidemiology Study (KoGES), we evaluated the dietary patterns (DPs) related to metabolic diseases and their associations with the incidence of non-fatal cardiovascular disease (CVD). After excluding those with a history of CVD or cancer, we analyzed the data of 8352 subjects aged 40-69 years. Based on their daily intake of 26 food groups at baseline, the DPs of the subjects with metabolic diseases (n = 1679, 20.1%) were analyzed using principal component analysis. Due to regional differences in the effect of DPs on CVD, we performed analyses stratified by region. The association between DPs and the incidence of non-fatal CVD was evaluated by calculating the hazard ratio (HR) and 95% confidence interval (CI) using the Cox proportional hazards model. During the 12-year follow-up, the incidence of non-fatal CVD was 5.4 per 1000 person-years (n = 431). An animal-based DP made the greatest contribution to the total variance and was characterized by a high intake of pork, beef, chicken, fish, and shellfish. The effect of DP on CVD differed by region (industrial/rural regions, p < 0.05) and was dominant in industrial regions, irrespective of metabolic disease status. In industrial regions, subjects in the top quintile of DP had a 0.42-fold (95% CI = 0.24-0.74) lower risk of incident CVD than those in the bottom quintile, even after adjusting for various covariates. In addition, the risk of CVD was high in individuals with a history of metabolic disease in both regions (HR = 1.74, 95% CI = 1.24-2.43 in industrial regions; HR = 1.88, 95% CI = 1.42-2.48 in rural regions). DP and a history of metabolic diseases, but not their interaction, were independently associated with incident CVD. In our study, an animal-based DP related to metabolic disease was independently associated with incident CVD, and this effect was noticeable only in industrial regions.

Role of Nutrition and Exercise Programs in Reducing Blood Pressure: A Systematic Review

The combined effect of diet and strength training (ST) on blood pressure (BP) seems to be very important for the treatment of prehypertension and hypertension (HT). Therefore, the aim of this study was to determine whether ST alone or combined with nutrition or supplementation has an impact on the arterial pressure reduction in normotensive and hypertensive populations. A systematic computerized literature search was performed according to the PRISMA guidelines using PubMed, Scopus and Google Scholar; only English language studies published from 1999 until 2018 were included. This systematic search identified the results of 303 individuals from nine studies. The ST program alone had a similar effectiveness as the nutrition program (NP) alone; however, their combination did not result in increased effectiveness in terms of a high BP reduction. The consumption of L-citrulline had a similar effect as ST on lowering BP; on the other hand, caffeine led to an increase in BP during the ST session. Our data suggest that a combination of ST 2-3 times a week at moderate intensity and a NP seems to be equally effective in terms of lowering BP (systolic and diastolic) as ST and NP alone.

Amino Acids and Hypertension in Adults

Accumulating evidence suggests a potential role of dietary protein among nutritional factors interfering with the regulation of blood pressure. Dietary protein source (plant versus animal protein), and especially, protein composition in terms of amino acids has been postulated to interfere with mechanisms underlying the development of hypertension. Recently, mounting interest has been directed at amino acids in hypertension focusing on habitual dietary intake and their circulating levels regardless of single amino acid dietary supplementation. The aim of the present review was to summarize epidemiological evidence concerning the connection between amino acids and hypertension. Due to the large variability in methodologies used for assessing amino acid levels and heterogeneity in the results obtained, it was not possible to draw robust conclusions. Indeed, some classes of amino acids or individual amino acids showed non-causative association with blood pressure as well as the incidence of hypertension, but the evidence was far from being conclusive. Further research should be prompted for a thorough understanding of amino acid effects and synergistic actions of different amino acid classes on blood pressure regulation.

James Lind Alliance research priorities: what role do carbohydrates, fats and proteins have in the management of Type 2 diabetes, and are there risks and benefits associated with particular approaches?

AIMS

To assess the role played by carbohydrates, fat and proteins in the management of Type 2 diabetes.

BACKGROUND

Diabetes research tends to reflect the interests of academics or the pharmaceutical industry, rather than those of people living with Type 2 diabetes. The James Lind Alliance and Diabetes UK addressed this issue by defining the research priorities of people living with Type 2 diabetes. Three of the top 10 research priority questions focused on lifestyle.

METHODS

A narrative review was undertaken with a structured search strategy using three databases. Search terms included the three macronutrients and Type 2 diabetes. No restrictions were placed on macronutrient quantity or length of study follow-up. Outcomes included changes in HbA_1c , body weight, insulin sensitivity and cardiovascular risk.

RESULTS

There is no strong evidence that there is an optimal ratio of macronutrients for improving glycaemic control or reducing cardiovascular risk. Challenges included defining the independent effect of macronutrient manipulation and identifying the effects of macronutrients, independent of foods and dietary patterns. Extreme intakes of macronutrients may be associated with health risks.

CONCLUSIONS

It is challenging to formulate food-based guidelines from studies based on macronutrient manipulation. Structured education should be offered to support individuals in discovering their optimal, individual dietary approach. Recommendations for dietary guidelines should be expressed in terms of foods and not macronutrients.

Dietary protein and changes in markers of cardiometabolic health across 20 years of follow-up in middle-aged Americans

OBJECTIVE

Dietary protein plays a role in counteracting age-related muscle loss. However, limited long-term data exist on protein intake and markers of cardiometabolic health, which tend to deteriorate with age.

DESIGN

Prospective cohort study. FFQ-derived protein intake (g/d) and cardiometabolic markers were assessed up to five times across 20 years. Markers included systolic (SBP) and diastolic (DBP) blood pressures, circulating lipids (total, HDL and LDL cholesterol; TAG), estimated glomerular filtration rate (eGFR), fasting glucose (FG), weight and waist circumference (WC). Mixed models accounting for repeated measures were used to estimate adjusted mean annualized changes in outcomes per quartile category of protein.

SETTING

Framingham Heart Study Offspring cohort, USA.

SUBJECTS

Participants (n 3066) with 12 333 unique observations, baseline (mean (sd)) age=54·0 (9·7) years, BMI=27·4 (4·9) kg/m2, 53·5 % female.

RESULTS

In fully adjusted models, there were favourable associations (mean (se)) of total protein with annualized changes in SBP (lowest v. highest intake: 0·34 (0·06) v. 0·04 (0·06) mmHg, P trend=0·001) and eGFR (-1·03 (0·06) v. -0·87 (0·05) ml/min per 1·73 m2, P trend=0·046), unfavourable associations with changes in FG (0·013 (0·004) v. 0·028 (0·004) mmol/l, P trend=0·004) and no associations with weight, WC, DBP or lipids. Animal protein was favourably associated with SBP and unfavourably with FG and WC; plant protein was favourably associated with FG and WC.

CONCLUSIONS

The present study provides evidence that protein intake may influence changes in cardiometabolic health independent of change in weight in healthy adults and that protein's role in cardiometabolic health may depend on the protein source.

A Systematic Review of Renal Health in Healthy Individuals Associated with Protein Intake above the US Recommended Daily Allowance in Randomized Controlled Trials and Observational Studies

A systematic review was used to identify randomized controlled trials (RCTs) and observational epidemiologic studies (OBSs) that examined protein intake consistent with either the US RDA (0.8 g/kg or 10-15% of energy) or a higher protein intake (≥20% but <35% of energy or ≥10% higher than a comparison intake) and reported measures of kidney function. Studies (n = 26) of healthy, free-living adults (>18 y old) with or without metabolic disease risk factors were included. Studies of subjects with overt disease, such as chronic kidney, end-stage renal disease, cancer, or organ transplant, were excluded. The most commonly reported variable was glomerular filtration rate (GFR), with 13 RCTs comparing GFRs obtained with normal and higher protein intakes. Most (n = 8), but not all (n = 5), RCTs reported significantly higher GFRs in response to increased protein intake, and all rates were consistent with normal kidney function in healthy adults. The evidence from the current review is limited and inconsistent with regard to the role of protein intake and the risk of kidney stones. Increased protein intake had little or no effect on blood markers of kidney function. Evidence reported here suggests that protein intake above the US RDA has no adverse effect on blood pressure. All included studies were of moderate to high risk of bias and, with the exception of 2 included cohorts, were limited in duration (i.e. <6 mo). Data in the current review are insufficient to determine if increased protein intake from a particular source, i.e., plant or animal, influences kidney health outcomes. These data further indicate that, at least in the short term, higher protein intake within the range of recommended intakes for protein is consistent with normal kidney function in healthy individuals.

Dietary amino acids and incidence of hypertension: A principle component analysis approach

The current study aimed to investigate the association between dietary amino acid patterns and incidence of hypertension, using principal components factor analyses. This study was conducted within the framework of Tehran Lipid and Glucose Study on 4288 adults, who were free of hypertension at baseline (2008–2011) and were followed for three years (2011–2014). Principal component factor analyses were conducted based on eight amino acid groups and three amino acid patterns were extracted. The first pattern was characterized by branched chain, aromatic, and alcoholic amino acids, and proline. Acidic amino acids and proline were highly loaded in the second pattern and the third was characterized by sulphuric and small amino acids. Adjusted odds ratio of the highest quartile of the first pattern was 1.83 (95%CI: 1.21–2.77, P for trend = 0.002) compared to the lowest one. The first pattern had high positive correlation with dietary intakes of animal protein and dairy, but was negatively correlated with plant protein, fruit, and vegetable. There was no significant association for the second and third patterns. Findings indicate that the dietary amino acid pattern, rich in branched chain, aromatic, and alcoholic amino acids, and proline could increase the risk of hypertension.

High dietary intake of aromatic amino acids increases risk of hypertension

Recent studies investigated the relation between amino acids and blood pressure. Our aim was to examine the association between intake of aromatic amino acids (AAAs) and risk of hypertension. A total of 4288 individuals, aged 20-70 years, participants of the Tehran Lipid and Glucose Study, who were free of hypertension at baseline (2008-2011), were followed for 3 years (2011-2014). Average intakes of AAAs including phenylalanine, tyrosine, and tryptophan were collected using a valid and reliable food frequency questionnaire at baseline. Adjusted logistic regression models were used to report odds ratio (OR) of hypertension across quartiles of AAAs. At the end of follow-up, 429 (10%) hypertension cases were ascertained. The adjusted OR of hypertension for percentage of AAAs from total protein intakes was 1.63 (95% confidence interval, 1.06-2.50; P for trend: .03) when comparing the highest quartile to the lowest. Furthermore, in the adjusted analyses, a statistically significant positive relationship was observed between the highest versus the lowest quartile intake of phenylalanine (OR = 1.66; 95% confidence interval, 1.14-2.47; P for trend: .03). However, there was no significant association of tyrosine and tryptophan intakes with hypertension risk. Our data suggest that AAAs may increase the risk of incident hypertension.

Association of Animal and Plant Proteins Intake with Hypertension in Iranian Adult Population: Isfahan Healthy Heart Program

Background:

There is evidence regarding the relationship between dietary proteins intake and blood pressure (BP), but they had inconsistent results. Therefore, this study was designed to assess the association between different kinds of protein intake (animal and plant protein) and BP.

Materials and Methods:

Data were collected from Isfahan Healthy Heart Program. We performed a cross-sectional study among 9660 randomly selected Iranian adults aged ≥19-year-old that they were selected from three large Iranian regions in 2007. A simplified validated 48-item-food frequency questionnaire was used to assess dietary intake including all kinds of protein. Systolic and diastolic BPs were measured in duplicate by trained personnel using a standard protocol. Multivariable regressions were applied to assess the relationship between protein intake and BP levels and the presence of hypertension (HTN).

Results:

More frequent consumption of animal, plant, and total protein intake were inversely associated with BP in a crude model (P < 0.001); however, after adjustment for potential confounders this relationship remained only for plant protein (P = 0.04). The risk of HTN occurrence decreased in the highest quintile of total and plant protein consumption by 19% (odds ratio [OR] = 0.81; confidence interval [CI]: [0.65–0.96]; P for trend = 0.004) and 18% (OR = 0.82; [CI: (0.67–0.94]; P for trend = 0.03), respectively.

Conclusions:

More frequent protein intake, especially plant protein consumption was inversely associated with BP and risk of HTN among Iranian adults.