Relations between protein intake and blood pressure in Japanese men and women: the Circulatory Risk in Communities Study (CIRCS)

Association between plant and animal proteins intake with lipid profile and anthropometric indices: A cross-sectional study

BACKGROUND

Results of studies on the effects of plant and animal proteins on lipid profile are controversial. So we aimed to assess the relationship between plant and animal protein intake with lipid profile and novel anthropometric indices in healthy individuals.

METHOD

In this cross-sectional study, 236 participants have selected from Shiraz medical centers (Iran) through random cluster sampling. Food intakes were assessed using a 168-items food frequency questionnaire (FFQ). Total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglyceride (TG) were measured. Anthropometric indices including a body shape index (ABSI), abdominal volume index (AVI), buddy roundness index (BRI), and conicity index (CI) were calculated.

RESULTS

In the crude and fully adjusted models, more consumption of plant proteins was associated with TG levels (OR = 2.31; 95% CI: 1.08, 4.95; P = 0.03 and OR = 2.39; 95% CI: 1.03, 5.15; P = 0.04). Also, there was a significant direct association between plant proteins and BRI in the curd model (OR = 3.55; 95% CI: 1.32, 9.54; P = 0.01), and after adjusting for age and energy intake (OR = 3.32; 95% CI: 1.21, 9.14; P = 0.01). More consumption of plant proteins was related to higher CI in the crude model (OR = 3.06; 95% CI: 1.12, 8.31; P = 0.03), but not in the fully adjusted model.

CONCLUSION

We found that a higher intake of plant proteins was associated with a higher TG level, BRI, and CI index. However, more research is needed to confirm these relations and provide the evidence needed to exert these findings into clinical practice.

Adherence to aerobic training combined with high protein intake is associated with low blood pressure in Italian older adults: a cross-sectional study

BACKGROUND

Lifestyle habits have a key role in cardiometabolic health. The effects of combined aerobic training (AT) and high protein intake (HPI) on cardiometabolic parameters in older adults are not well established.

AIMS

To investigate the association of AT and HPI with blood pressure (BP), blood glucose, and total blood cholesterol levels in a sample of Italian older adults enrolled in the Longevity Check-up 7 + (Lookup 7 +) study.

METHODS

Lookup 7 + is an ongoing project started in June 2015 and conducted in unconventional settings (e.g., exhibitions, malls, health promotion campaigns) across Italy with the aim of fostering adoption of healthy lifestyles in the general population. For the present investigation, analyses were conducted in participants 65 + years and with body mass index values ≥ 18.5 kg/m2 (n = 3219). Systolic (SBP) and diastolic BP (DBP), blood glucose, and total blood cholesterol were measured. Protein intake was estimated using a 12-item food frequency questionnaire. HPI was operationalized as a daily protein intake ≥ 0.8 g/kg of body weight. AT was operationalized as the practice of running and/or swimming for 60 + minutes at least twice weekly during the previous year.

RESULTS

The mean age of the 3219 participants was 72.7 ± 5.7 years, and 55.2% were women. Adherence to AT combined with a HPI was negatively and independently associated with SPB (β: - 4.976; 95% confidence interval: - 9.8 to - 0.08). No other significant associations were observed.

DISCUSSION AND CONCLUSIONS

Our results indicate that AT combined with HPI was negatively associated with SBP in a large and relatively unselected sample of Italian older adults living in the community. These findings need confirmation by ad hoc designed studies.

Engagement in Aerobic Exercise Is Associated with a Reduced Prevalence of Sarcopenia and Severe Sarcopenia in Italian Older Adults

The present study was conducted to test the association between adherence to specific exercise modalities and sarcopenia severity in Italian older adults. Data were collected as part of the ongoing Longevity Check-Up 7+ (Lookup 7+) project. Lookup 7+ began in June 2015 and has since been conducted in unconventional settings (e.g., exhibitions, malls, social events) throughout Italy. In the present study, we used data on adults 65 years and older. Sarcopenia was identified according to the simultaneous presence of dynapenia and low appendicular muscle mass. Muscle strength was measured by isometric handgrip and sit-to-stand (STS) testing. Sarcopenia was categorized as severe if participants reported difficulty or inability to walk 400 m. Engagement in running and/or swimming (RS) or strength training with or without stretching (SS) was used to define exercise modalities. Analyses were conducted in 3289 participants (mean age: 72.7 ± 5.7 years; 1814 women). The results of the binary regression showed negative associations between RS and the presence of STS-based sarcopenia in women, and between RS and STS-based severe sarcopenia in men. Collectively, these findings indicate that RS is negatively associated with the presence of sarcopenia in large sample of relatively unselected Italian older adults.

Protein Intake Is Associated with Blood Pressure and Cholesterol Levels in Italian Older Adults: A Cross-Sectional Study

The present study was conducted to test the association between protein intake and blood pressure, glucose levels, and blood cholesterol in a large sample of Italian older adults. Longevity Check-up 7+ (Lookup 7+) is an ongoing project that started in June 2015. The project is conducted in unconventional settings (e.g., exhibitions, malls, health promotion campaigns) across Italy with the aim of fostering adoption of healthy lifestyles in the general population. For the present study, participants were eligible if they were 65+ years and provided written informed consent. Systolic (SBP) and diastolic blood pressure (DBP), and blood glucose and cholesterol levels were assessed. Protein intake was estimated using a 12-item food frequency questionnaire. Three-thousand four-hundred and four older adults were included in the study. The results of the linear regression showed an inverse association between protein intake (as a continuous variable) and DBP, and a positive correlation with blood cholesterol levels. The findings of the present study indicate that a high intake of protein was negatively associated with DBP and positively associated with total blood cholesterol levels in a large cohort of Italian older adults, after adjustment for numerous covariates.

High Protein Intake at Lunch Is Negatively Associated with Blood Pressure in Community-Dwelling Older Adults: A Cross-Sectional Study

BACKGROUND

The present study was conducted to explore the association between protein intake across the main meals and hypertension (HTN)-related parameters in community-dwelling Brazilian older adults.

METHODS

Brazilian community-dwelling older adults were recruited in a senior center. Dietary habits were assessed through 24 h recall. Protein intake was classified as high and low according to median and recommended dietary allowance values. Absolute and body weight (BW)-adjusted protein consumption levels were quantified and analyzed according to ingestion across the main meals. Systolic (SBP) and diastolic blood pressure (DBP) were measured using an oscilometric monitor. Participants were categorized as hypertensive according to physician diagnosis or the detection of high SBP and/or DBP values.

RESULTS

One hundred ninety-seven older adults were enrolled in the present study. Protein intake at lunch was independently and negatively associated with SBP. Furthermore, a lower prevalence of HTN (diagnosed by a physician) was observed in participants with higher intakes of protein. These results remained significant after adjustment for many covariates. However, significance was lost when kilocalories and micronutrients were included in the model.

CONCLUSIONS

Findings of the present study indicate that protein intake at lunch was independently and negatively associated with systolic BP in community-dwelling older adults.

Non-Dairy Animal Protein Consumption Is Positively Associated with Overweight and Obesity in Israeli Adolescents

Protein consumption apparently plays a role in weight control. This cross-sectional study examined the association of protein consumption in Israeli adolescents with overweight/obesity. 7th−12th grade students participating in a national school-based survey (2015−2016) completed self-administered questionnaires, including a food frequency questionnaire, and height and weight measurements (n = 3443, 48% males, 15.2 ± 1.6 years). WHO growth standards served to define weight status. Intakes of total protein and protein source were calculated. Multivariable logistic regression analyses evaluated associations with overweight/obesity (BMI z-score ≥ 1), adjusting for possible covariates. Total protein intake (median (IQR)) was 62.5 (45.5, 85.7) g/d, accounting for 12.0 (10.5, 13.6) percent of daily energy. Of participants, 31.4% were overweight/obese. In multivariable models, overweight/obesity was positively associated with incremental increases of 10 g/d in total protein intake (OR = 1.07, 95% CI: 1.02−1.12, p < 0.01), total animal protein intake (OR = 1.05, 95% CI: 1.01−1.10, p = 0.026), and non-dairy animal protein intake (OR = 1.06, 95% CI: 1.01−1.11, p = 0.029). No associations were found with plant or dairy protein intake. These associations remained when protein intake was reported as a percentage of daily energy and when overweight and obesity were analyzed individually. High daily protein intakes, principally from non-dairy animal sources, were positively associated with overweight/obesity in adolescents. Additional studies are needed to establish causality of these findings.

A review of recent evidence of dietary protein intake and health

The Korea National Health and Nutrition Examination Survey of 2013 to 2017 reported that the average protein consumption of the Korean population is above the current recommended nutrient intake of protein proposed by the Dietary Reference Intakes for Koreans. Some health professionals and the media often advise consuming diets high in protein for promoting metabolic regulation, weight control, and muscle synthesis. However, due to lack of scientific evidence, the validity and safety of high protein consumption are yet to be fully ascertained. The present review assesses recent evidence published in 2014-2020 from human studies, focusing on adequate protein intake and protein sources for the prevention of chronic diseases, particularly metabolic disorders and sarcopenia.

Evaluating type and amount of dietary protein in relation to metabolic syndrome among Iranian adults: cross-sectional analysis of Fasa Persian cohort study

BACKGROUND AND AIM

Metabolic syndrome is characterized by several conditions including abdominal obesity, dyslipidemia, impaired glucose levels, and hypertension; which all are directly associated with an increased risk of cardiovascular disease and type 2 diabetes mellitus. This study aimed to evaluate the association of the amount and source of dietary protein with the risk of metabolic syndrome and its components in adult men and women.

MATERIAL AND METHOD

This study was performed using Persian cohort data, Fasa branch, which included 3660 men and 5262 women. Individuals were divided into five groups for total dietary proteins, plant proteins, and animal proteins using the quintiles, and the odds of incidence for metabolic syndrome and each component was evaluated.

RESULTS

A higher intake of total protein was associated with lower odds of having metabolic syndrome (OR: 0.24 95% CI 0.18-0.33, P-trend < 0.001 in men, OR: 0.42 95% CI 0.34-0.51, P-trend < 0.001 in women) and all of its components. men (OR: 0.35 95% CI 0.25-0.48, P-trend < 0.001) and women (OR: 0.41 95% CI 0.33-0.52, P-trend < 0.001) in the highest quintile of plant protein intake had a reduced prevalence of metabolic syndrome and its components. An increased animal protein intake was associated with a lower prevalence of metabolic syndrome (P-trend < 0.001), a declined risk of having elevated triglycerides (P-trend = 0.016) in men, and a reduced risk of having abdominal obesity in men (P-trend < 0.001) and women (P-trend < 0.001).

CONCLUSION

A higher consumption of total protein and plant protein was associated with a lower prevalence of metabolic syndrome and its components. Increased consumption of animal protein seemed to be related to a lower prevalence abdominal obesity. Also, only in men, animal protein was associated with decreased risk of having metabolic syndrome.

Association between Protein Intake and the Risk of Hypertension among Chinese Men and Women: A Longitudinal Study

This study aimed to examine the relationship between hypertension risk and protein intake in Chinese individuals. Our analysis included 7007 men and 7752 women from 9 China Health and Nutrition Survey waves (1991−2015). The main outcome was incident hypertension. Dietary intake was recorded using a combination of 3 consecutive 24-h recalls and a household food inventory survey. Energy-adjusted cumulative average intakes were analyzed, and Cox proportional hazards regression models were built. After 143,035 person-years of follow-up, 2586 and 2376 new male and female hypertension cases were identified, respectively. In multivariate-adjusted models with dietary protein intakes included as categorical variables, higher animal protein intake was associated with lower hypertension risk in women (p-trend = 0.01), whereas non-significant in men. Plant protein intake showed a significant positive correlation with hypertension risk, while non-significant for total protein. On a continuous scale, restricted cubic spline curves visually revealed L-, J-, and U-shaped associations between hypertension risk and animal-, plant-, and total-protein intakes, respectively, in both sexes (all p-nonlinearity < 0.0001). Our results suggest a beneficial association between intakes of animal, plant, and total proteins and hypertension risk at lower intake levels, and excessive intake of plant or total protein may increase the hypertension risk in the Chinese population.

Dietary protein intake, kidney function, and survival in a nationally representative cohort

BACKGROUND

High-protein diets (e.g., Paleo, Atkins, South Beach, ketogenic) have gained popularity as a means to promote weight loss and avoid excess carbohydrate consumption. Yet in chronic kidney disease (CKD) patients, evidence suggests low dietary protein intake (DPI) leads to attenuation of kidney function decline, although concerns remain for risk of protein-energy wasting.

OBJECTIVES

To examine associations of DPI with mortality in a nationally representative cohort of US adults, stratified by kidney function.

METHODS

We examined the association between daily DPI scaled to actual body weight (ABW), ascertained by 24-h dietary recall, with all-cause mortality among 27,604 continuous NHANES adult participants (1999-2010), stratified according to impaired versus normal kidney function (estimated glomerular filtration rates <60 compared with ≥60 ml/min/1.72 m2, respectively), using multivariable Cox models. We also examined the relation between high biological value (HBV) protein consumption with mortality.

RESULTS

In participants with impaired kidney function, a high DPI of ≥1.4 g/kg ABW/day was associated with higher mortality, while lower DPI levels were not associated with mortality (reference, 0.6 to <1.0 g/kg ABW/day): the adjusted HRs (aHRs) were 1.09 (95% CI: 0.90, 1.32), 1.03 (95% CI: 0.82, 1.29), and 1.37 (95% CI: 1.02, 1.85) for DPI <0.6, 1.0 to <1.4, and ≥1.4 g/kg ABW/day, respectively. Yet in participants with normal kidney function, a low DPI of <0.6 g/kg ABW/day was associated with higher mortality, whereas higher DPI levels were not associated with death: the aHRs were 1.18 (95% CI: 1.04, 1.34), 0.92 (95% CI: 0.81, 1.04), and 0.99 (95% CI: 0.85, 1.16) for DPI <0.6, 1.0 to <1.4, and ≥1.4 g/kg ABW/day, respectively. The highest 2 tertiles of HBV consumption were associated with higher mortality in participants with impaired kidney function.

CONCLUSIONS

Among participants with impaired kidney function, a higher DPI and greater HBV consumption were associated with higher mortality, whereas a lower DPI was associated with higher mortality in those with normal kidney function. Further studies are needed to elucidate the specific pathways between higher DPI and mortality in CKD.

The impact of type of dietary protein, animal versus vegetable, in modifying cardiometabolic risk factors: A position paper from the International Lipid Expert Panel (ILEP)

Proteins play a crucial role in metabolism, in maintaining fluid and acid-base balance and antibody synthesis. Dietary proteins are important nutrients and are classified into: 1) animal proteins (meat, fish, poultry, eggs and dairy), and, 2) plant proteins (legumes, nuts and soy). Dietary modification is one of the most important lifestyle changes that has been shown to significantly decrease the risk of cardiovascular (CV) disease (CVD) by attenuating related risk factors. The CVD burden is reduced by optimum diet through replacement of unprocessed meat with low saturated fat, animal proteins and plant proteins. In view of the available evidence, it has become acceptable to emphasize the role of optimum nutrition to maintain arterial and CV health. Such healthy diets are thought to increase satiety, facilitate weight loss, and improve CV risk. Different studies have compared the benefits of omnivorous and vegetarian diets. Animal protein related risk has been suggested to be greater with red or processed meat over and above poultry, fish and nuts, which carry a lower risk for CVD. In contrast, others have shown no association of red meat intake with CVD. The aim of this expert opinion recommendation was to elucidate the different impact of animal vs vegetable protein on modifying cardiometabolic risk factors. Many observational and interventional studies confirmed that increasing protein intake, especially plant-based proteins and certain animal-based proteins (poultry, fish, unprocessed red meat low in saturated fats and low-fat dairy products) have a positive effect in modifying cardiometabolic risk factors. Red meat intake correlates with increased CVD risk, mainly because of its non-protein ingredients (saturated fats). However, the way red meat is cooked and preserved matters. Thus, it is recommended to substitute red meat with poultry or fish in order to lower CVD risk. Specific amino acids have favourable results in modifying major risk factors for CVD, such as hypertension. Apart from meat, other animal-source proteins, like those found in dairy products (especially whey protein) are inversely correlated to hypertension, obesity and insulin resistance.

Association between meat intake and mortality due to all-cause and major causes of death in a Japanese population

PURPOSE

We examined the association between meat intake and mortality due to all-cause and major causes of death using a population-based cohort study in Japan.

METHODS

87,507 Japanese aged between 45 and 74 years old at 5-year follow-up study were followed for 14.0 years on average. Associations between meat intake and mortality risk were assessed using a Cox proportional hazards model.

RESULTS

A heavy intake of total meat was associated with a higher risk of all-cause mortality relative to the lowest quartile intake in men (Q4: HR,1.18; 95%CIs, 1.06-1.31). A higher intake of total meat was associated with a lower risk of stroke mortality in women (Q2: HR, 0.70; 95%CIs, 0.51-0.94, Q3: HR, 0.68; 95%CIs, 0.50-0.95, Q4: HR, 0.66; 95%CIs, 0.44-0.99). A heavy intake of red meat was also associated with all-cause mortality (Q4: HR, 1.13; 95%CIs, 1.02-1.26) and heart disease mortality (Q4: HR, 1.51; 95%CIs, 1.11-2.06) in men but not in women. Heavy intake of chicken was inversely associated with cancer mortality in men.

CONCLUSIONS

Heavy intakes of total and red meat were associated with an increase in all-cause and heart disease mortality in men, while total meat intake was associated with a lower risk of stroke mortality in women.

Animal Protein Intake Is Positively Associated with Metabolic Syndrome Risk Factors in Middle-Aged Korean Men

Few studies have examined the relationship of protein intake by food source with metabolic syndrome in Korean adults, even though animal food intake has increased. This study examined the association between plant and animal protein intake and metabolic syndrome among middle-aged Korean adults. A total of 13,485 subjects aged 30-64 years were selected from the 2013-2018 Korea National Health and Nutrition Examination Survey. Protein intake was assessed using 24-h dietary recall data and divided into quintiles. Men had a higher percentage of energy intake from animal protein (7.4%) than plant protein (6.9%). Men in the highest quintile group of animal protein intake had a higher prevalence of abdominal obesity (OR: 1.30, 95% CI: 1.00-1.70), reduced high-density lipoprotein cholesterol (HDL-C) (OR: 1.43, 95% CI: 1.07-1.90), and elevated fasting glucose (OR: 1.32, 95% CI: 1.01-1.74), after adjusting for covariates. Furthermore, stronger associations of animal protein intake with abdominal obesity were shown in men who consumed less than estimated energy requirements (OR: 1.60, 95% CI: 1.11-2.31). Plant protein intake was negatively associated with increased blood pressure in men. Neither animal nor plant protein intakes were significantly associated with any of the metabolic syndrome risk factors in women. The results imply that lower animal protein intake may be a beneficial factor for metabolic syndrome management in middle-aged Korean men.

Animal and Plant Protein Sources and Cardiometabolic Health

The sources or types of protein in the diet have long been overlooked regarding their link to cardiometabolic health. The picture is complicated by the fact that animal and plant proteins are consumed along with other nutrients and substances which make up the "protein package" so plant and animal protein come with clear nutrient clusters. This review aimed at deciphering the relation between plant and animal protein and cardiometabolic health by examining different nutritional levels (such as amino acids, protein type, protein foods, protein patterns, and associated overall dietary and nutrient patterns) and varying levels of scientific evidence [basic science, randomized controlled trials (RCTs), observational data]. Plant protein in Western countries is a robust marker of nutrient adequacy of the diet, whereas the contribution of animal protein is highly heterogeneous. Yet recent data from large cohorts have confirmed that total and animal proteins are associated with the risk of cardiovascular disease and diabetes, even when fully adjusting for lifestyle and dietary or nutritional factors. Here again, there is marked variability depending on the type of animal protein. Protein from processed red meat and total red meat on the one hand, and from legumes, nuts, and seeds on the other, are often reported at the extremes of the risk range. RCTs using purified proteins have contributed little to the topic to date, inasmuch as the findings cannot readily be extrapolated to current or near-future diets, but RCTs studying whole protein foods have shown a beneficial effect of pulses. Despite the fact that many of the benefits of plant protein reported in observational or interventional studies may stem from the protein package that they convey and the nutrients that they displace, there are also important indications that protein per se may affect cardiometabolic health via the many amino acids that are present in typically contrasting levels in plant compared with animal proteins.

Vegetable Protein Intake was Inversely Associated with Cardiovascular Mortality in a 15-Year Follow-Up Study of the General Japanese Population

AIM

To examine the relationship between the intake of dietary vegetable protein and CVD mortality in a 15-year follow-up study of a representative sample of the Japanese population.

METHODS

A total of 7,744 participants aged 30 years or older (3,224 males and 4,520 females) who were free of CVD at baseline were included in this analysis. Vegetable protein intake (% energy) was assessed using a three-day semi-weighed dietary record at baseline. Multivariable-adjusted hazard ratios (HRs) were calculated using Cox's proportional hazards model after adjusting for confounding factors.

RESULTS

The total person-years studied were 107,988 with a mean follow-up period of 13.9 years. There were 1,213 deaths during the follow-up period, among which 354 (29.2%) were due to CVD. Vegetable protein intake was associated inversely with CVD and cerebral hemorrhage mortality, with the HRs for a 1% energy increment in vegetable protein intake being 0.86 (95% CI, 0.75-0.99) and 0.58 (95% CI, 0.35-0.95), respectively. In the subgroup analysis of participants with or without hypertension, the inverse association between vegetable protein intake and CVD mortality was more evident in the nonhypertensive group, with the HRs for CVD and stroke being 0.68 (95% CI, 0.50-0.94) and 0.50 (95% CI, 0.30-0.84), respectively.

CONCLUSIONS

Vegetable protein intake may prevent future CVD, particularly in nonhypertensive subjects in the Japanese population. However, further studies are necessary to examine the biological mechanisms of this effect.

Ovo-vegetarian diet is associated with lower systemic blood pressure in Taiwanese women

OBJECTIVE

This study was designed to investigate blood pressure (BP) profiles among Taiwanese women with different dietary patterns.

STUDY DESIGN

Cross-sectional study.

METHODS

A total of 269 non-hypertensive Taiwanese women, 40 years of age or older, were surveyed using structured questionnaires, and measurements of BP and physiological parameters were made. To assess differences among vegans, ovo-vegetarians, and meat eaters in terms of BP, demographic, and health behavior data, the chi-squared and Fisher's exact tests were employed for categorical variables, and analysis of variance and independent t-tests were performed for continuous variables. Multiple regression analysis was used to examine the relationship between BP and dietary patterns while controlling for potential confounding factors.

RESULTS

A significant difference was found among the three test groups in terms of age, education, employment, stress, and waist-hip ratio. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) significantly differed among the three groups. After controlling for age, body weight, waist circumference, and hip circumference, the three groups were observed to be a significant risk factor of the SBP and DBP. The SBP and DBP of the ovo-vegetarian group were significantly lower than those of the meat-eater group. No significant differences were found between the vegan and meat-eater groups in terms of SBP and DBP.

CONCLUSION

Dietary pattern is a likely risk factor for SBP and DBP outcomes in Taiwanese women. In particular, the SBP and DBP of ovo-vegetarians are the lowest among the values observed for all dietary patterns. This finding suggests that an ovo-vegetarian diet is beneficial for long-term BP control and prevention of hypertension in females.

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.

Animal Proteins as Important Contributors to a Healthy Human Diet

Adequate protein intake is critical for health and development. Generally, protein of animal origin is of higher quality for humans owing to its amino acid pattern and good digestibility. When administered in mixtures it can enhance the quality of plant proteins, but its availability is often low in low-income communities, especially in young children, the elderly, and pregnant and lactating women, who have increased requirements and in whom high-quality protein also stimulates (bone) growth and maintenance. Although high protein intake was associated with increased type 2 diabetes mellitus risk, milk and seafood are good sources of branched chain amino acids and taurine, which act beneficially on glucose metabolism and blood pressure. However, high consumption of protein-rich animal food is also associated with adverse health effects and higher risk for noncommunicable diseases, partly related to other components of these foods, like saturated fatty acids and potential carcinogens in processed meat but also the atherogenic methionine metabolite homocysteine. In moderation, however, animal proteins are especially important for health maintenance in vulnerable persons.

Plant Protein Intake and Dietary Diversity Are Independently Associated with Nutrient Adequacy in French Adults

BACKGROUND

Plant protein intake, which is favorably associated with the intake of many nutrients, is a marker of a healthy diet. However, the higher nutrient adequacy of diets rich in plant protein may also originate from overarching factors associated with more healthful dietary behaviors, such as a greater dietary diversity.

OBJECTIVE

Our main objective was to determine whether the relation between plant protein intake and nutrient adequacy could be explained, at least in part, by an association with overall dietary diversity.

METHODS

We used data from 1330 adults participating in the French Nutrition and Health Survey [Etude Nationale Nutrition Santé (ENNS); 2006-2007]. With the use of global, integrative approaches, we assessed nutrient adequacy [by using the probabilistic PANDiet (Probability of Adequate Nutrient Intake) scoring system] and overall dietary diversity (by using a 100-point score that accounts for the relative number of subgroups consumed in 7 food groups). Linear multivariate modeling was used for the analysis.

RESULTS

We found a positive association between plant protein (but not total or animal protein) intake and dietary diversity (β = 0.08) and a strong positive association between dietary diversity and nutrient adequacy (β = 0.33). However, the association between plant protein intake and nutrient adequacy was not explained by dietary diversity (r = 0.38 and partial r = 0.36, P < 0.0001). In multivariate analysis, nutrient adequacy was positively associated with dietary diversity (β = 0.44) and plant (β = 0.37) and animal (β = 0.15) protein intakes. Associations persisted after adjustment for potential confounders (total energy, energy density, sex, body mass index, income, occupational status, educational level, region, season, and smoking status).

CONCLUSIONS

Overall dietary diversity is greater in French adults who consume more plant protein. Both plant protein intake and dietary diversity are associated with the nutrient adequacy of the diet. But the plant protein-nutrient adequacy association was not related to the relative overall diversity of the diet.

Amino Acid Intakes Are Inversely Associated with Arterial Stiffness and Central Blood Pressure in Women

BACKGROUND

Although data suggest that intakes of total protein and specific amino acids (AAs) reduce blood pressure, data on other cardiovascular disease risk factors are limited.

OBJECTIVE

We examined associations between intakes of AAs with known mechanistic links to cardiovascular health and direct measures of arterial stiffness, central blood pressure, and atherosclerosis.

METHODS

In a cross-sectional study of 1898 female twins aged 18-75 y from the TwinsUK registry, intakes of 7 cardioprotective AAs (arginine, cysteine, glutamic acid, glycine, histidine, leucine, and tyrosine) were calculated from food-frequency questionnaires. Direct measures of arterial stiffness and atherosclerosis included central systolic blood pressure (cSBP), mean arterial pressure (MAP), augmentation index (AI), pulse wave velocity (PWV), and intima-media thickness (IMT). ANCOVA was used to assess the associations between endpoints of arterial stiffness and intake (per quintile), adjusting for potential confounders.

RESULTS

In multivariable analyses, higher intakes of total protein and 7 potentially cardioprotective AAs were associated with lower cSBP, MAP, and PWV. Higher intakes of glutamic acid, leucine, and tyrosine were most strongly associated with PWV, with respective differences of -0.4 ± 0.2 m/s (P-trend = 0.02), -0.4 ± 0.2 m/s (P-trend = 0.03), and -0.4 ± 0.2 m/s (P-trend = 0.03), comparing extreme quintiles. There was a significant interaction between AA intakes and protein source, and higher intakes of AAs from vegetable sources were associated with lower central blood pressure and AI. Higher intakes of glutamic acid, leucine, and tyrosine from animal sources were associated with lower PWV.

CONCLUSIONS

These data provide evidence to suggest that intakes of several AAs are associated with cardiovascular benefits beyond blood pressure reduction in healthy women. The magnitude of the observed associations was similar to those previously reported for other lifestyle factors. Increasing intakes of these AAs could be an important and readily achievable way to reduce cardiovascular disease risk.

Diet quality and adherence to a healthy diet in Japanese male workers with untreated hypertension

OBJECTIVES

As Japanese societies rapidly undergo westernisation, the prevalence of hypertension is increasing. We investigated the association between dietary quality and the prevalence of untreated hypertension in Japanese male workers.

DESIGN AND METHODS

We conducted a cross-sectional study of 433 male workers who completed a brief food frequency questionnaire. Adherence to the WHO-based Healthy Diet Indicator (HDI), the American Heart Association 2006 Diet and Lifestyle Recommendations, the Dietary Approaches to Stop Hypertension (DASH) diet, and Mediterranean-style diet was assessed using four adherence indexes (HDI score, AI-84 score, DASH score and MED score). Hypertension classes were classified into three categories: non-hypertension, untreated hypertension and treated hypertension (ie, taking antihypertensive medication).

RESULTS

The prevalence of untreated hypertension and treated hypertension was 22.4% and 8.5%, respectively. Patients with untreated hypertension had significantly lower HDI and AI-84 scores compared with non-hypertension. DASH and MED scores across the three hypertension classes were comparable. After adjusting for age, energy intake, smoking habit, alcohol drinking, physical activity and salt intake, a low adherence to HDI and a lowest quartile of AI-84 score were associated with a significantly higher prevalence of untreated hypertension, with an OR of 3.33 (95% CI 1.39 to 7.94, p=0.007) and 2.23 (1.09 to 4.53, p=0.027), respectively.

CONCLUSIONS

A lower dietary quality was associated with increased prevalence of untreated hypertension in Japanese male workers. Our findings support a potential beneficial impact of nutritional assessment using diet qualities.

Association of height with peripheral arterial disease in type 2 diabetes

OBJECTIVE

To investigate whether height is associated with peripheral arterial disease (PAD) in patients with type 2 diabetes.

RESEARCH DESIGN AND METHODS

This was an observational study performed in 4,528 Chinese patients with type 2 diabetes. Anthropometric measures and the ankle-brachial index (ABI) were performed on each subject. PAD was defined as those patients with a history of revascularization or amputation due to ischemia, or an ABI <0.9.

RESULTS

A total of 23.3 % of T2DM patients had PAD (men 22.9 % and women 23.7 %). The mean age and height were 57.8 ± 12.5 years and 170.5 cm for men, and 60.0 ± 11.7 years and 158.9 cm for women, respectively. The ABI and frequency of PAD were higher with decreasing height quartiles. An inverse association was observed between height- and gender-adjusted risk of PAD. This relationship remained unchanged following further adjustment for potential confounders. Subjects in the shortest stature group had of 1.174 times higher risk of PAD for men and 1.143 times for women, compared with those in the tallest stature group. The multivariate adjusted hazard ratios (95 % CI) of PAD for a 10-cm height increase were 0.85 (95 % CI 0.78-0.94).

CONCLUSION

A short stature seems to be associated with higher risk of PAD in Chinese diabetic patients. However, the cross-sectional nature of the study limits conclusions regarding the direction or causality. Further longitudinal study is warranted in this and other ethnic groups.

Plant and animal protein intakes are differently associated with nutrient adequacy of the diet of French adults

The sustainability of dietary plant and animal protein consumption is an important issue, but few data are available to ascertain the health-related impact of animal and plant protein intake. The objective was to study the relationships between animal and plant protein intake and diet quality, as reflected by an integrated index of nutrient adequacy. Using data on 1912 adults from the French Individual and National Consumption Survey 2 (2006-2007), we assessed diet quality by using the PANDiet, a unique score combining 35 probabilities of having an adequate nutrient intake, and used multiple regression analysis to study the relationship with intakes of plant, animal, and related food source proteins. After adjustments for intakes of energy, alcohol, and protein from other sources and sociodemographic factors, plant protein intake was positively associated with the PANDiet, irrespective of sex (β = 0.50, P < 0.0001). By contrast, total and animal protein intakes were differently associated with the PANDiet according to sex, with a positive association in women (β = 0.07 and β = 0.08, respectively; P < 0.01) and an inverse association in men (β = -0.07 and β = -0.05, respectively; P < 0.01). The relationships between the PANDiet and intakes of protein from animal food sources varied: for instance, associations were inverse for red meat and poultry in men but not in women, whereas irrespective of sex, they were positive for fish, milk, and yogurt and inverse for processed meat, cheese, and eggs. These findings show that plant protein is a robust marker of a healthy diet, whereas total animal protein includes different subtypes of animal protein that largely vary in their relationship with diet quality. These data could help refine protein recommendations from a qualitative and dietary standpoint.

Adult height and body mass index in relation to risk of total stroke and its subtypes: the circulatory risk in communities study

BACKGROUND

Several studies have reported that height and risk of stroke are inversely associated based on the hypothesis that height is a marker of childhood physical condition. However, a limited number of studies have taken account of the effect of current physical condition on the relationship between height and risk of stroke.

METHODS

We conducted a prospective cohort study of 12,222 40- to 69-year-old Japanese patients under systematic surveillance for stroke incidence. Because body mass index (BMI) is regarded as a surrogate marker of current physical condition for cardiovascular risk, we performed a stratified analysis of this risk based on BMI.

RESULTS

During the median 17-year follow-up, there were 565 incident strokes (326 ischemic and 186 hemorrhagic strokes) showing an inverse association between height and risk of stroke independent of classical cardiovascular risk factors. Compared with the lowest height group (<159 cm for men and <148 cm for women) as reference, the multivariable hazard ratios (HRs) and 95% confidence intervals (95% CIs) for the highest height group (>166 cm for men and >154 cm for women) were 0.70 (95% CI 0.49-1.00; P = .043) for men and 0.44 (95% CI 0.27-0.70; P < .001) for women. When the analysis was restricted to those with BMI <23 kg/m(2), the associations were stronger for both hemorrhagic and ischemic stroke.

CONCLUSIONS

Height was found to be inversely associated with risk of stroke for middle-aged Japanese men and women, especially with lower BMIs. Our findings suggest that childhood social and physical conditions may contribute to the development of stroke in adulthood because height is a surrogate marker of these conditions.

Association between dietary protein intake and the risk of hypertension: a cross-sectional study from rural western China

Evidence for an association between dietary proteins and the risk of hypertension in rural Chinese adults, whose diets are protein-poor and unbalanced, is limited. The aim of this study was to investigate the effect of dietary proteins on hypertension among adults of rural western China. A cross-sectional survey was conducted in Hanzhong, China, and 2241 residents were included in the analysis. Logistic regression models were used to examine whether dietary proteins (total, plant and animal protein) were independently correlated with hypertension. The total protein intake was inadequate (51.7 g per day for male and 40.1 g per day for female), accounting for 56-71% of the Chinese recommended nutrient intakes or adequate intakes. Nearly 80% of protein intake derived from plants, especially grains, and the proportion derived from plants was higher in females than in males. The daily animal protein intake was 12.1 g for males and 8.3 g for females. For females, no significant association was found between hypertension and total protein or plant protein intake. However, animal protein intake was significantly and negatively associated with the risk of hypertension after controlling for demographic characteristics, lifestyle factors, body mass index and other dietary nutrients. In addition, the odds ratio for the upper quartile compared with the bottom quartile was 0.64 (95% confidence interval, CI: 0.43-0.95, P for trend <0.05). Furthermore, a significant decrease of 1.082 mm Hg (95%CI: 0.189-1.975) in systolic blood pressure and 0.668 mm Hg (95%CI: 0.105-1.232) in diastolic blood pressure was observed per s.d. increase of animal protein intake in females. For males, we did not observe a significant association between dietary proteins and hypertension or blood pressure. In conclusion, for the western rural Chinese population, especially women, whose dietary protein intake is low and largely derived from plants, the intake of animal protein may be related to a decreased risk of hypertension.

Health-risk factors and the prevalence of hypertension: cross-sectional findings from a national cohort of 87,143 Thai Open University students

BACKGROUND

Thailand is undergoing a health-risk transition which increases chronic diseases, particularly hypertension, as a result of a rapid transition from a developing to a developed country. This study analyzes the effect of health-risk factors such as demography, socioeconomic status (SES) and body mass index (BMI) on the prevalence of hypertension.

METHODS

This was a cross-sectional analysis using data obtained in 2005 from 87,143 Sukhothai Thammathirat Open University (STOU) students participating in the Thai Cohort Study (mean age 30.5 years, 54.7% female). Adjusted odds ratios of the association between risk factors and hypertension were analysed across two age groups by sex, after controlling for the confounding factors such as SES and BMI.

RESULTS

The prevalence of hypertension in men was approximately twice as high as that in women (6.9% vs 2.6%). Hypertension was associated with ageing, a lower education attainment, a higher BMI and having underlying diseases in both sexes. In men, hypertension was associated with being single, having a high income, spending more time on screens (TV & PC), cigarette smoking and drinking alcohol. In women, it was directly correlated with instant and roasted or smoked food consumption.

CONCLUSIONS

Hypertension was highly associated with obesity and having underlying disease. The Thai health-risk transition is in a later stage. Thais should now be educated about the danger of high blood pressure and the protective power of a low fat and low salt diet, and a normal BMI. Cessation of smoking and moderation in alcohol intake should be promoted.

Association between dietary behavior and risk of hypertension among Japanese male workers

Dietary behavior can worsen or prevent hypertension. However, data on the association between dietary behavior and the risk of hypertension in Asians are limited. The aim of this study was to determine these associations in Japanese male workers. We conducted a prospective study of 30-71-year-old Japanese male workers in Osaka, Japan, between 2001 and 2011. The study subjects were 3486 normotensive males who were assessed for an average of 4.6 years using an annual survey. We defined hypertension by a systolic blood pressure of ≥140 mm Hg, a diastolic blood pressure of ≥90 mm Hg and/or the use of antihypertensive medications. Dietary behavior questionnaires were included in the annual surveys. For each question on dietary behavior, we calculated the odds ratios (ORs) for the risk of hypertension using logistic regression models. We used subjects who consistently gave affirmative answers in the baseline and end-point surveys as a reference. The number of new cases of hypertension was 846 among 3486 subjects. Compared with subjects who eat meat frequently, subjects who did not eat meat frequently showed a higher risk of hypertension (OR=1.26, 95% confidence interval (CI): 1.00-1.59). Subjects who did not consume dairy products every day showed a higher risk of hypertension (OR=1.39, 95% CI: 1.13-1.71) compared with those who did. Meat and dairy product intake was associated with the prevention of hypertension among Japanese male workers.

Antihypertensive effects of dietary protein and its mechanism

Hypertension is a leading cause of morbidity and mortality worldwide. Individuals with hypertension are at increased risk of stroke, heart disease and kidney failure. Both genetic and lifestyle factors, particularly diet, have been attributed an important role in the development of hypertension. Reducing dietary sugar and salt intake can help lower blood pressure; similarly, adequate protein intake may also attenuate hypertension. Observational, cross-sectional and longitudinal epidemiological studies, and controlled clinical trials, have documented significant inverse associations between protein intake and blood pressure. Human and animal studies have shown that specific amino acids within proteins may have antihypertensive effects. Cysteine, glutathione (a tripeptide), glutamate and arginine attenuate and prevent alterations that cause hypertension including insulin resistance, decreased nitric oxide bioavailability, altered renin angiotensin system function, increased oxidative stress and formation of advanced glycation end products. Leucine increases protein synthesis in skeletal muscle and improves insulin resistance by modulating hepatic gluconeogenesis. Taurine and tryptophan attenuate sympathetic nervous system activity. Soy protein helps lower blood pressure through its high arginine content and antioxidant activity exhibited by isoflavones. A diet containing an ample amount of protein may be a beneficial lifestyle choice for individuals with hypertension; one example is the Dietary Approaches to Stop Hypertension (DASH) diet, which is low in salt and saturated fat; includes whole grains, lean meat, poultry, fish and nuts; and is rich in vegetables, fruits and low-fat dairy products, which are good sources of antioxidant vitamins, minerals and fibre. Including an adequate supply of soy in the diet should also be encouraged.

Central adiposity and protein intake are associated with arterial stiffness in overweight children

Being overweight is associated with vascular abnormalities, which are important in the development of atherosclerosis. However, little is known about dietary and lifestyle determinants of vascular function in overweight children. In adults, dietary protein and milk intake are associated with reduced blood pressure and reduced risk of metabolic syndrome. This study examined the associations between dietary protein, milk intake, physical activity, and adiposity on arterial stiffness in overweight children. In a cross-sectional study, overweight children with habitual milk intakes ≤ 250 mL/d were examined by DXA scans, pedometer counts, anthropometry, and metabolic variables. Dietary intake was registered for 4 d. The outcomes were arterial stiffness measured by pulse wave velocity (PWV) (n = 182) and augmentation index (Aix) (n = 183). The PWV (mean ± SD) was 4.78 ± 0.72 m/s and the Aix was -0.77 ± 9.44%. In multivariate models, the android fat:gynoid fat and android fat:body fat ratios were positively associated with PWV (β = 1.49 and β = 10.3, both P < 0.05) and Aix (β = 28.3, P < 0.01 and β = 153, P < 0.05), whereas the gynoid fat:body fat ratio was negatively associated with the Aix (β = -134; P < 0.001). Protein intake (percentage energy) was positively associated with PWV (β = 0.05; P < 0.01). Milk intake (L/d) tended to be negatively associated with PWV (β = -0.64; P = 0.05). Pedometer counts were negatively associated with the Aix; however, the association became nonsignificant after controlling for HOMA, which was positively associated with the Aix (β = 0.95; P < 0.01). In conclusion, central adiposity and protein intake are associated with increased arterial stiffness measured as PWV in overweight children independent of blood pressure and heart rate. The effect of protein intake may be caused by meat, because the milk intake was low.

Protein and coronary heart disease: the role of different protein sources

Meat protein is associated with an increase in risk of heart disease. Recent data have shown that meat protein appeared to be associated with weight gain over 6.5 years, with 1 kg of weight increase per 125 g of meat per day. In the Nurses' Health Study, diets low in red meat, containing nuts, low-fat dairy, poultry, or fish, were associated with a 13% to 30% lower risk of CHD compared with diets high in meat. Low-carbohydrate diets high in animal protein were associated with a 23% higher total mortality rate whereas low-carbohydrate diets high in vegetable protein were associated with a 20% lower total mortality rate. Recent soy interventions have been assessed by the American Heart Association and found to be associated with only small reductions in LDL cholesterol. Although dairy intake has been associated with a lower weight and lower insulin resistance and metabolic syndrome, the only long-term (6 months) dairy intervention performed so far has shown no effects on these parameters.

Sources of dietary protein in relation to blood pressure in a general Dutch population

Background

Little is known about the relation of different dietary protein types with blood pressure (BP). We examined whether intake of total, plant, animal, dairy, meat, and grain protein was related to BP in a cross sectional cohort of 20,820 Dutch adults, aged 20–65 y and not using antihypertensive medication.

Design

Mean BP levels were calculated in quintiles of energy-adjusted protein with adjustment for age, sex, BMI, education, smoking, and intake of energy, alcohol, and other nutrients including protein from other sources. In addition, mean BP difference after substitution of 3 en% carbohydrates or MUFA with protein was calculated.

Results

Total protein and animal protein were not associated with BP (p_trend = 0.62 and 0.71 respectively), both at the expense of carbohydrates and MUFA. Systolic BP was 1.8 mmHg lower (p_trend<0.01) in the highest (>36 g/d) than in the lowest (<27 g/d) quintile of plant protein. This inverse association was present both at the expense of carbohydrates and MUFA and more pronounced in individuals with untreated hypertension (−3.6 mmHg) than in those with normal (+0.1 mmHg) or prehypertensive BP (−0.3 mmHg; p_interaction<0.01). Meat and grain protein were not related to BP. Dairy protein was directly associated with systolic BP (+1.6 mmHg, p_trend<0.01), but not with diastolic BP (p_trend = 0.24).

Conclusions

Total protein and animal protein were not associated with BP in this general untreated Dutch population. Plant protein may be beneficial to BP, especially in people with elevated BP. However, because high intake of plant protein may be a marker of a healthy diet and lifestyle in general, confirmation from randomized controlled trials is warranted.

Sources of dietary protein and risk of hypertension in a general Dutch population

Evidence suggests a small beneficial effect of dietary protein on blood pressure (BP), especially for plant protein. We examined the relationship between several types of dietary protein (total, plant, animal, dairy, meat and grain) and the risk of hypertension in a general population of 3588 Dutch adults, aged 26–65 years, who were free of hypertension at baseline. Measurements were done at baseline and after 5 and 10 years of follow-up. Hazard ratios (HR), with 95 % CI, for incident hypertension were obtained in tertiles of energy-adjusted protein, using time-dependent Cox regression models. Models were adjusted for age, sex, BMI, education, smoking, baseline systolic BP, dietary confounders and protein from other sources (if applicable). Mean BP was 118/76 mmHg at baseline. Protein intake was 85 (sd 22) g/d (approximately 15 % of energy) with 62 % originating from animal sources. The main sources of protein were dairy products (28 %), meat (24 %) and grain (19 %). During the follow-up, 1568 new cases of hypertension were identified (44 % of the participants). Energy-adjusted intake of total protein, plant protein and animal protein was not significantly associated with hypertension risk (all HR approximately 1·00, P>0·60). Protein from grain showed a significant inverse association with incident hypertension, with a HR of 0·85 (95 % CI 0·73, 1·00, Ptrend = 0·04) for the upper tertile ( ≥ 18 g/d) v. the lower tertile ( < 14 g/d), whereas dairy protein and meat protein were not associated with incident hypertension. In conclusion, higher intake of grain protein may contribute to the prevention of hypertension, which warrants confirmation in other population-based studies and randomised controlled trials.

Effect of dietary protein supplementation on blood pressure: a randomized, controlled trial

BACKGROUND

Observational studies have reported an inverse association between dietary protein intake and blood pressure (BP). We compared the effect of soy protein, milk protein, and carbohydrate supplementation on BP among healthy adults.

METHODS AND RESULTS

We conducted a randomized, double-blind crossover trial with 3 intervention phases among 352 adults with prehypertension or stage 1 hypertension in New Orleans, LA, and Jackson, MS, from September 2003 to April 2008. The trial participants were assigned to take 40 g/d soy protein, milk protein, or carbohydrate supplementation each for 8 weeks in a random order. A 3-week washout period was implemented between the interventions. Three BPs were measured at 2 baseline and 2 termination visits during each of 3 intervention phases with a random-zero sphygmomanometer. Compared with carbohydrate controls, soy protein and milk protein supplementations were significantly associated with -2.0 mm Hg (95% confidence interval -3.2 to -0.7 mm Hg, P=0.002) and -2.3 mm Hg (-3.7 to -1.0 mm Hg, P=0.0007) net changes in systolic BP, respectively. Diastolic BP was also reduced, but this change did not reach statistical significance. There was no significant difference in the BP reductions achieved between soy or milk protein supplementation.

CONCLUSIONS

The results from this randomized, controlled trial indicate that both soy and milk protein intake reduce systolic BP compared with a high-glycemic-index refined carbohydrate among patients with prehypertension and stage 1 hypertension. Furthermore, these findings suggest that partially replacing carbohydrate with soy or milk protein might be an important component of nutrition intervention strategies for the prevention and treatment of hypertension.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00107744.

A Japanese health success story: trends in cardiovascular diseases, their risk factors, and the contribution of public health and personalized approaches

There has been a substantial decline in mortality from stroke and ischemic heart disease (IHD) in Japan between the 1960s and 2000s, which contributed to placing Japanese at the top of world’s life expectancy rankings. That mortality decline was attributable to reductions of blood pressure and smoking, in spite of increases in dyslipidemia and diabetes mellitus. The combination of public health and personalized treatment activities to enhance sodium reduction, balanced diets, smoking prevention/cessation as well as hypertension detection and treatment have contributed to the reduction of cardiovascular diseases, demonstrated by a community-based stroke prevention program. The health success story, however, contains an underlying concern about future health threats, the plateaued IHD mortality decline and increased IHD incidence among urban middle-aged men, probably due to increased dyslipidemia and diabetes. The IHD incidence and mortality trends need to be monitored because of a potential future problem for predictive, preventive and personalized medicine.

Lifestyle and cardiovascular disease in Japan

The aim was to give on overview of the profile of cardiovascular disease, vascular pathology and the relationships between lifestyle and cardiovascular disease in Japanese. Compared with the United States and Europe, the higher mortality from stroke and lower mortality from coronary heart disease constitute a unique cardiovascular profile for Japan. A selective review of population-based pathology, trend and prospective cohort studies was performed to clarify the characteristics of cardiovascular disease and vascular pathology, trends in the incidence and mortality of cardiovascular disease, and the relationships between lifestyle and cardiovascular disease among Japanese adults. Since the 1970s, mortality from coronary heart disease as well as stroke has declined substantially in Japan, probably due to a major decline in blood pressure levels and for men a more recent decline in smoking, in spite of an increase in body mass index and total cholesterol levels. However, the decline in mortality was smaller and plateaued in middle-aged men aged 30-49 in the metropolitan cities of Tokyo and Osaka. The incidence of coronary heart disease has increased among middle-aged men residing in the suburbs of Osaka. As for the associations between lifestyle and cardiovascular disease, higher sodium, lower calcium and lower animal protein content in the diet and for men higher alcohol consumption may account for the higher prevalence of hypertension and higher risk of stroke for Japanese than for western populations. On the other hand, lower saturated fat (meat) and higher n3 polyunsaturated fat (fish) in the Japanese diet may contribute to the lower prevalence of hypercholesterolemia and lower risk of coronary heart disease among Japanese. Japan is unique among developed countries in that coronary heart disease mortality has been low and has continued to decline, while stroke mortality has declined substantially. However, a recent trend for coronary heart disease incidence to increase among urban men is a cause for concern as a potential source of future problems for public health and clinical practice in Japan.

Plant and animal protein intake and its association with overweight and obesity among the Belgian population

The objective of the present study was to assess animal and plant protein intakes in the Belgian population and to examine their relationship with overweight and obesity (OB). The subjects participated in the Belgian National Food Consumption Survey conducted in 2004. Food consumption was assessed by using two non-consecutive 24 h dietary recalls. About 3083 participants ( ≥ 15 years of age; 1546 males, 1537 females) provided completed dietary information. Animal protein intake (47 g/d) contributed more to total protein intakes of 72 g/d than plant protein intake, which accounted for 25 g/d. Meat and meat products were the main contributors to total animal protein intakes (53 %), whereas cereals and cereal products contributed most to plant protein intake (54 %). Males had higher animal and plant protein intakes than females (P < 0·001). Legume and soya protein intakes were low in the whole population (0·101 and 0·174 g/d, respectively). In males, animal protein intake was positively associated with BMI (β = 0·013; P = 0·001) and waist circumference (WC; β = 0·041; P = 0·002). Both in males and females, plant protein intake was inversely associated with BMI (males: β = − 0·036; P < 0·001; females: β = − 0·046; P = 0·001) and WC (male: β = − 0·137; P < 0·001; female: β = − 0·096; P = 0·024). In conclusion, plant protein intakes were lower than animal protein intakes among a representative sample of the Belgian population and decreased with age. Associations with anthropometric data indicated that plant proteins could offer a protective effect in the prevention of overweight and OB in the Belgian population.

Adult height and the risk of cardiovascular disease among middle aged men and women in Japan

An inverse association between height and risk of cardiovascular disease has been reported, but the evidence is limited for stroke subtypes, in particular in Asian populations. Further, few studies have examined how socioeconomic status in adulthood influence the relationship between height and risk of cardiovascular disease. This study examined the association between height and risks of stroke and coronary heart disease, and whether education level, an indicator of adult socioeconomic status, modify the effect of height on those risks, within a cohort of the Japan Public Health Center-based Prospective Study (JPHC Study). The hazard ratios for the incidence of cardiovascular disease associated with height were calculated by a 16-year follow-up of 15,564 Japanese men and women, aged 40-59. The hazard ratios were adjusted for age, gender, area, education, occupation and cardiovascular risk factors. Height was inversely associated with risks of total stroke, either hemorrhagic or ischemic stroke but not with coronary heart disease. The adjusted hazard ratios (95% confidence interval (CI)) of total stroke, hemorrhagic stroke, and ischemic stroke for a 1 SD height increments were 0.82 (95% CI: 0.74, 0.90), 0.80 (95% CI: 0.70, 0.92), and 0.83 (95% CI: 0.73, 0.95), respectively. No multiplicative interaction was observed between height and education level on stroke risk. Short stature was associated with increased risk of total stroke, either hemorrhagic or ischemic stroke, independent of adult socioeconomic status and cardiovascular risk factors, but not with risk of coronary heart disease in Japanese men and women.

Dietary protein and blood pressure: a systematic review

BACKGROUND

Elevated blood pressure (BP), which is a major risk factor for cardiovascular disease, is highly prevalent worldwide. Recently, interest has grown in the role of dietary protein in human BP. We performed a systematic review of all published scientific literature on dietary protein, including protein from various sources, in relation to human BP.

METHODOLOGY/PRINCIPAL FINDINGS

We performed a MEDLINE search and a manual search to identify English language studies on the association between protein and blood pressure, published before June 2010. A total of 46 papers met the inclusion criteria. Most observational studies showed no association or an inverse association between total dietary protein and BP or incident hypertension. Results of biomarker studies and randomized controlled trials indicated a beneficial effect of protein on BP. This beneficial effect may be mainly driven by plant protein, according to results in observational studies. Data on protein from specific sources (e.g. from fish, dairy, grain, soy, and nut) were scarce. There was some evidence that BP in people with elevated BP and/or older age could be more sensitive to dietary protein.

CONCLUSIONS/SIGNIFICANCE

In conclusion, evidence suggests a small beneficial effect of protein on BP, especially for plant protein. A blood pressure lowering effect of protein may have important public health implications. However, this warrants further investigation in randomized controlled trials. Furthermore, more data are needed on protein from specific sources in relation to BP, and on the protein-BP relation in population subgroups.

Urea nitrogen concentrations in spot urine, estimated protein intake and blood pressure levels in a Japanese general population

BACKGROUND

An inverse association between total protein intake and blood pressure has been reported in Western countries. Such evidence is limited in the Japanese population, however, whose major protein sources are plants and seafood.

METHODS

We conducted a population-based cross-sectional study of 986 men and 1,636 women, aged 40-74 years, in a Japanese rural community to examine the association between blood pressure levels and urea nitrogen concentrations in spot urine.

RESULTS

The concentration of urea nitrogen in spot urine, an indicator of total protein intake that was validated by 24-h urea nitrogen excretion and 24-h dietary research, was inversely associated with systolic blood pressure levels for men: a 238 mg/dl increase in urea nitrogen concentration was associated with a 2.1 mm Hg lower mean systolic blood pressure. For women, a weaker and nonsignificant inverse association was observed. There was no association between urea nitrogen concentrations and diastolic blood pressure levels in either sex. Total protein intake estimated from spot urine was also inversely associated with systolic blood pressure levels for men: a 19.2 g/day increase in estimated protein intake was associated with a 1.5 mm Hg lower mean systolic blood pressure.

CONCLUSION

A urinary biomarker for total protein intake was inversely associated with systolic blood pressure levels for men in a Japanese general population.

Egg consumption and CHD and stroke mortality: a prospective study of US adults

OBJECTIVE

To evaluate the relationship between egg consumption and CHD and stroke mortality using the Third National Health and Nutrition Examination Survey 1988-1994 (NHANES III) and follow-up survey.

DESIGN

A cross-sectional survey using a stratified, multi-stage probability sample was analysed, adjusting for survey design. Egg consumption was obtained from the FFQ and separated into categories of egg intake. Hazard ratios (HR) were calculated for CHD and stroke mortality using multivariate Cox regression models.

SETTING

A health and nutrition survey conducted in the USA from 1988 to 1994 with follow-up through 31 December 2000.

SUBJECTS

The study population included men and women who were free of CVD and had completed a FFQ at baseline.

RESULTS

Multivariate models adjusting for health, lifestyle and dietary factors indicated that 'high' egg consumption (≥ 7 times/week v. <1 time/week) was not associated with significantly increased CHD mortality (HR = 1·13, 95 % CI 0·61, 2·11 (men); HR = 0·92, 95 % CI 0·27, 3·11 (women)). There was a statistically significant inverse association between 'high' egg consumption and stroke mortality among men (HR = 0·27, 95 % CI 0·10, 0·73), but the estimate was imprecise because of sparse data. We did not observe a statistically significant positive association between 'high' egg consumption and CHD or stroke mortality in analyses restricted to individuals with diabetes, but these analyses may be limited due to the small number of diabetics.

CONCLUSIONS

We did not find a significant positive association between egg consumption and increased risk of mortality from CHD or stroke in the US population. These results corroborate the findings of previous studies.