Independent contribution of dairy products and calcium intake to blood pressure variations at a population level

Effect of Yogurt Intake Frequency on Blood Pressure: A Cross-Sectional Study

Yogurt consumption is a significant factor in reducing the risk of hypertension and preventing cardiovascular diseases. Although increasing evidence has emerged regarding the potential benefits of probiotics in hypertension, there is a lack of large, cross-sectional studies assessing the association between yogurt intake and blood pressure parameters. We aimed to evaluate the association between yogurt intake frequency and blood pressure. A cross-sectional study was designed using data from the National Health and Nutrition Examination Survey from 2003 to 2004 and 2005 to 2006. We included 3, 068 adults with blood pressure data and yogurt intake data. Multivariate regression analyses revealed significant inverse associations between yogurt and systolic blood pressure (P < 0.05), diastolic blood pressure (P < 0.05), and mean arterial pressure (P < 0.05) in nonhypertensive participants (n = 1 822) but not in hypertensive participants (n = 1 246). Furthermore, a high frequency of yogurt intake prevented hypertension; however, no additional antihypertensive effects were observed in patients already diagnosed with hypertension.

Higher Doses of Calcium Associated With Survival in Trauma Patients

INTRODUCTION

Calcium is required for coagulation, cardiac output, and peripheral vascular resistance. Between 85% and 94% of trauma patients treated with massive blood transfusion develop hypocalcemia.1 The aim of this study is to evaluate the relationship between increased intravenous calcium administration during massive transfusion and improved survival of trauma patients.

METHODS

We performed a retrospective analysis of trauma patients who received massive transfusion over a 2-y period. Doses of elemental calcium administered per unit of blood product transfused were calculated by calcium to blood product ratio (CBR). Chi-square test evaluated association between coagulopathy and 30-d mortality. Two-sample t-test evaluated association between CBR and coagulopathy. Bivariate regression analysis evaluated association between CBR and blood products transfused per patient. Multivariable logistic regression analysis, controlling for age, sex, coagulopathy, and Injury Severity Score evaluated the association between CBR and mortality.

RESULTS

The study included 77 patients. Coagulopathy was associated with increased 30-d mortality (P < 0.05). Patients who survived had higher CBR than those who died (P < 0.05). CBR was associated with a significant reduction in total blood products transfused per patient (P < 0.05). CBR was not associated with coagulopathy (P = 0.24). Multivariable logistic regression analysis demonstrated that Injury Severity Score ≥16, coagulopathy and decreased CBR were significant predictors of mortality (P < 0.05). CBR above 50 mg was a predictor of survival (P < 0.05).

CONCLUSIONS

Higher doses of calcium given per blood product transfused were associated with improved 30-d survival and decreased blood product transfusions.

Comparative Analysis of Dietary and Supplemental Intake of Calcium and Vitamin D among Canadian Older Adults with Heart Disease and/or Osteoporosis in 2004 and 2015

Despite the role of calcium and vitamin D in osteoporosis and heart disease, little research has examined changes in the intake of calcium and vitamin D among individuals with these conditions over time. Using data from the 2004 and 2015 Canadian Community Health Surveys, we investigated changes in dietary and supplemental intake of calcium and vitamin D among Canadian older adults aged ≥ 50 years, both with and without heart disease and/or osteoporosis, between 2004 and 2015. Notable declines in dietary calcium intake occurred, particularly among non-supplement users. Surprisingly, individuals with osteoporosis and heart disease, who are at higher nutritional risk, were less likely to use calcium supplements in 2015 compared to 2004. Among calcium supplement users, those with osteoporosis or both conditions experienced significant reductions in their usual calcium intake in 2015, with an increased proportion failing to meet recommended intake levels. Conversely, vitamin D supplement users experienced a substantial rise in vitamin D intake in 2015. In 2015, only a small proportion of supplement users did not meet the recommended vitamin D intake levels. These findings underscore the importance of public health initiatives to facilitate safe increases in calcium and vitamin D intake for older adults, particularly those with heart disease and osteoporosis.

The benefit of vegetarian diets for reducing blood pressure in Taiwan: a historically prospective cohort study

OBJECTIVE

Past vegetarians research has often found that they have lower blood pressure (BP). Effects may include their lower BMI and higher intake levels of fruit and vegetables. Besides, the study pursues to extend this evidence in a diverse population containing vegans, lacto-ovo vegetarians and omnivores.

DESIGN

The study analyzed data on five hundred vigorous individuals aged 20 years or older from a standard medical screening program and provided validated questionnaire. Criteria were established for vegan, lacto-ovo vegetarian, partial vegetarian and omnivorous dietary patterns.

SETTING

Health screening programs were conducted at a standard medical screening program in Taiwan between 2006 and 2017. Dietary data were gathered by self-administered questionnaire.

SUBJECTS

Five hundred Taiwanese subjects representing the cohort.

RESULTS

Multiple regression analyses confirmed that the vegan vegetarians had lower systolic and diastolic BP (mmHg) than omnivorous Taiwanese (β =  - 6.8, p < 0.05 and β =  - 6.9, p < 0.001). Findings for lacto-ovo vegetarians (β =  - 9.1, p < 0.001 and β =  - 5.8, p < 0.001) were similar. The vegetarians were also less likely to be using antihypertensive medications. Defining hypertension as systolic BP > 139 mmHg or diastolic BP > 89 mmHg or routine of antihypertensive medications, the odds ratio of hypertension compared with omnivores was 0.37 (95% CI = 0.19-0.74), 0.57 (95% CI = 0.36-0.92) and 0.92 (95% CI = 0.50-1.70), respectively, for vegans, lacto-ovo vegetarians and partial vegetarians. Results were reduced after adjustment for BMI.

CONCLUSIONS

The study concludes from this relatively large study that vegetarians, especially vegans, with otherwise diverse characteristics but stable diets, do have lower systolic and diastolic BP and less hypertension than omnivores.

The effect of calcium gluconate administration during cardiopulmonary bypass on hemodynamic variables in infants undergoing open-heart surgery

Background

The incidence of complications after heart surgery is a critical factor in disability, deaths, lengthening hospital stays, and increasing treatment costs. The metabolic balance of certain hormones and electrolytes is necessary for proper cardiac function. In children, various biochemical conditions may cause calcium depletion during heart surgery. The purpose of this study was to determine the effect of calcium gluconate administration during cardiopulmonary bypass on hemodynamic variables and clinical outcomes in infants undergoing open-heart surgery. This study was conducted at Rajaie Cardiovascular Medical and Research Center in 2021 using a controlled randomized clinical trial. A total of 60 patients with open-heart surgery weighing up to 10 kg were included in the study. The first group received an intravenous injection of calcium gluconate 20 min after opening the aortic clamp, and the second group was monitored as a control group. Data collection tools included checklists containing demographics, surgical information, and intensive care unit measures.

Results

The Chi-square test or Fisher's exact test showed that the frequency distribution of gender, blood group, Rhesus factor (RH), and clinical diagnosis in the two groups of intervention and control was not statistically significant (p < 0.05). The mean and standard deviation of Ejection Fraction (EF) changes (before and after) were 13.27 ± 9.16 in the intervention group and 8.31 ± 9.80 in the control group (p = 0.065). The results of two-way repeated measures ANOVA showed that mean systolic blood pressure (p = 0.030), mean diastolic blood pressure (p = 0.021), mean heart rate (p = 0.025), mean arterial pressure (p = 0.020), mean pH (p < 0.001), and mean hemoglobin (p = 0.018) in the intervention, and control groups were statistically significant.

Conclusions

In the present study, unlike systolic pressure, mean diastolic blood pressure decreased, and mean arterial pressure increased significantly. As a result, the slope of changes during the study period was different in the intervention and control groups.

Associations of dietary patterns with blood pressure and markers of subclinical arterial damage in adults with risk factors for CVD

OBJECTIVE

Unhealthy diet is a modifiable risk factor leading to subclinical arterial damage (SAD), high BP and CVD. It was aimed to investigate the possible associations of dietary patterns (DPs) with SAD in adults having multiple CVD risk factors.

DESIGN

Dietary intake was evaluated through two 24-h dietary recalls and principal component analysis was used to identify DPs. Oscillometry, applanation tonometry with pulse wave analysis and carotid ultrasound were used to assess peripheral and aortic BP, arterial stiffness and pressure wave reflections.

SETTING

Laiko University Hospital, Athens, Greece.

PARTICIPANTS

A total of 470 individuals (53·1 ± 14·2 years) with CVD risk factors were enrolled.

RESULTS

A pattern characterised by increased consumption of whole-grain cereals, white meat and reduced consumption of sugar was positively associated with common carotid compliance (β = 0·01, 95 % CI 0·00, 0·01), whereas a pattern high in refined cereals, red and processed meat was positively associated with brachial but not aortic systolic pressure (β = 1·76, 95 % CI 0·11, 3·42) and mean arterial pressure (MAP) (β = 1·18, 95 % CI 0·02, -2·38). Low consumption of low-fat dairy products, high consumption of full-fat cheese and butter was positively associated with MAP (β = 0·97, 95 % CI 0·01, 1·95). Increased consumption of vegetables, fruits, fresh juices, fish and seafood was inversely associated with augmentation index (AIx) (β = -1·01, 95 % CI -1·93, -0·09).

CONCLUSION

Consumption of whole grains, white meat, fruits/vegetables, fish/seafood and avoidance of sugar was associated with improved SAD. Preference in refined grains, red/processed meat, high-fat cheese/butter and low intake of low-fat dairy products were associated with BP elevation. Future studies are needed to confirm the present findings.

Feasibility of Low-Sodium, High-Potassium Processed Foods and Their Effect on Blood Pressure in Free-Living Japanese Men: A Randomized, Double-Blind Controlled Trial

We aimed to verify the effect of new low-sodium high-potassium seasonings and processed foods containing poly-γ-glutamic acid on blood pressure in free-living settings. To this end, we conducted a randomized, double-blind controlled trial on 187 Japanese men, aged 35–67 years, who did not use antihypertensives. Participants were randomly allocated to an intervention (n = 93) or a control group (n = 94). They were given a boxed lunch and miso soup (average Na and K content for the intervention group: 1175 and 1476 mg; for the control group: 2243 and 703 mg, respectively). Blood pressure was measured three times every morning for 1 week immediately before and during the final week of the trial. On the day before and the final day of the intervention period, 24 h urine samples were collected. After intervention, the intervention group showed a significantly stronger decrease in the urinary sodium-to-potassium ratio than the control group (p < 0.001). The mean difference in systolic blood pressure change after adjustment for baseline values between the two groups was −2.1 (95% CI: −3.6, −0.6) mmHg. Compliance between the groups was similar, suggesting successful blinding. In conclusion, the use of new seasonings and processed foods aimed at lowering blood pressure in free-living settings may be feasible and effective.

Association between animal source foods consumption and risk of hypertension: a cohort study

PURPOSE

This study assessed the association between animal source foods (ASF) consumption and hypertension, a recognised risk factor for cardiovascular disease. Adverse effects of red and processed meat (RPM) consumption and beneficial effects of the consumption of dairy products and other ASF have been discovered separately; however, the constrained nature of food intake has been typically ignored. We assessed the effects of substituting RPM and other ASF.

METHODS

We followed-up 5394 Chinese adults (age 18-60 years) at baseline using the China Health and Nutrition Survey from 2004 to 2011. Food consumption was assessed using individual-based consecutive 24-h recall and household-based food weighing approaches. Both traditional substitution analysis and substitution analysis based on compositional transformation were used to assess substitution effects.

RESULTS

In total, 1267 participants were newly diagnosed with hypertension during the median follow-up time of 6.81 years (range, 2.97-6.99 years). The traditional substitution analysis found that substituting eggs for RPM was associated with a lower risk of hypertension. The compositional transformation substitution analysis revealed that replacing RPM with any other ASF was associated with a lower risk of hypertension; it implemented substitutions of one or many ASF for RPM; it also revealed different substitution effects of RPM and dairy products, and substituting dairy products for RPM was associated with reduced hypertension risks.

CONCLUSION

The compositional transformation substitution analysis considers the constrained and relative nature of food consumption. It is a flexible approach to estimating substitution effects using different patterns to obtain personalised estimation effects and provide individualised dietary recommendations.

Dairy product consumption and hypertension risk in a prospective French cohort of women

BACKGROUND

Among potentially modifiable factors, dairy product consumption has been inconsistently associated with hypertension risk. The objective of this study was to investigate the relation between dairy product consumption and the risk of hypertension among middle-aged women.

METHODS

In a prospective cohort of 40,526 French women, there were 9340 new cases of hypertension after an average 12.2 years of follow up. Consumptions of milk, yogurt, and types of cheese were assessed at baseline using a validated dietary questionnaire. Hazard ratios (HRs) and 95% confidence intervals (95% CI) for hypertension were estimated with multivariate Cox models with age as the time scale.

RESULTS

The mean dairy consumption was 2.2 + 1.2 servings/day, as cottage cheese (0.2 + 0.2 servings/day), yogurt (0.6 + 0.5 servings/day), milk (0.4 + 0.7 servings/day), and cheese (1.1 + 0.8 servings/day). There was no association between risk of hypertension and total dairy consumption (multivariate HR for the fifth vs. first quintile HR_5vs.1 = 0.97 [0.91; 1.04]). There was no association with any specific type of dairy, except for a positive association between processed cheese consumption and hypertension (multivariate HR_{4vs.1 =} 1.12 [1.06; 1.18]; p trend = < 0.003).

CONCLUSIONS

In this large prospective cohort of French women, overall consumption of dairy products was not associated with the risk of hypertension. Results regarding processed cheese must be further confirmed.

Dietary calcium intake and hypertension risk: a dose-response meta-analysis of prospective cohort studies

The association of calcium intake with risk of developing hypertension in the general population has not been established yet. We systematically searched PubMed and Scopus databases up to February 2018 to find prospective observational studies investigating the association of calcium intake with risk of developing hypertension. The reported risk estimates were pooled using a random-effects model. Eight prospective cohort studies (248,398 participants and 30,838 cases) were included. Seven studies measured dietary calcium intake, but one study measured total calcium intake (calcium from food and supplements). A significant inverse association was found for the highest versus lowest category of calcium intake (relative risk: 0.89, 95%CI: 0.86, 0.93; I² = 0%, n = 8), and for each 500 mg/d increment (relative risk: 0.93, 95%CI: 0.90, 0.97; I² = 64%, n = 7). Summary results were the same with the main analyses when the analyses were restricted only to dietary calcium intake. A nonlinear dose-response meta-analysis exhibited a linear inverse association, with a somewhat steeper trend within the low and moderate intakes. In conclusion, higher dietary calcium intake, independent of adiposity and intake of other blood pressure-related minerals, is slightly associated with a lower risk of developing hypertension.

Important roles of the Ca2+-sensing receptor in vascular health and disease

Ca²⁺-sensing receptor (CaSR), a member of G protein-coupled receptor family, is widely expressed in the vascular system, including perivascular neurons, vascular endothelial cells (VECs) and vascular smooth muscle cells (VSMCs). When stimulated, CaSR can further increase the cytosolic Ca²⁺ concentration ([Ca²⁺]_cyt) in two ways: intracellular Ca²⁺ release from endo/sarcoplasmic reticulum (ER/SR) and extracellular Ca²⁺ entry through Ca²⁺-permeable cation channels. In endothelium, increased Ca²⁺ subsequently activate nitric oxide synthase (NOS) and intermediate conductance Ca²⁺-activated K⁺ channels (IKCa), resulting in vasodilation through NOS-mediated NO release or membrane hyperpolarization. In VSMCs, CaSR-induced intracellular Ca²⁺ increase causes blood vessel constriction. CaSR activation predominantly induces vasorelaxation of whole vascular tissues through VECs-dependent mechanisms; however, CaSR-induced Ca²⁺ signaling in VSMCs may play a braking role in CaSR-mediated vasorelaxation. Emerging evidence reveals the importance of CaSR in the regulation of vascular tone and blood pressure. Here, we summarized recent advances in CaSR-mediated vascular reaction and the underlying mechanisms in different species, including humans. In addition, several studies have demonstrated that CaSR dysfunction may be associated with some fatal vascular diseases, such as pulmonary arterial hypertension, primary hypertension, diabetes, acute myocardial infarction and vascular calcification. With the advance of studies on CaSR in vascular health and disease, it is expected positive modulators or negative modulators of CaSR used for the treatment of specific diseases may be promising therapeutic options for the prevention and/or treatment of vascular diseases.

Regular Yogurt Intake and Risk of Cardiovascular Disease Among Hypertensive Adults

BACKGROUND

High blood pressure (HBP) is a major cardiovascular disease (CVD) risk factor. Clinical trials including Dietary Approaches to Stop Hypertension (DASH) have demonstrated beneficial effects of dairy consumption on risks of HBP and CVD. Yogurt, a fermented dairy product, may independently be related to CVD risk.

OBJECTIVE

To evaluate the association between yogurt consumption and CVD risk among hypertensive individuals in 2 large cohorts and to determine whether the association differs among those whose eating pattern more closely resembles the DASH diet.

METHODS

Overall, 55,898 female Nurses' Health Study (NHS) and 18,232 male Health Professionals Follow-Up Study (HPFS) participants with prevalent HBP were included. Cumulative average estimates of yogurt intake from validated food frequency questionnaires were related to verified self-reported CVD outcomes using Cox proportional hazards models. Hazard ratios and 95% confidence intervals (CI) were adjusted for CVD risk factors, medications, and diet covariates.

RESULTS

Yogurt intake was inversely associated with CVD risk (myocardial infarction and stroke) among hypertensive participants (P <0.01 in both cohorts). Among participants consuming ≥2 servings/week of yogurt, NHS women had a 17% (95% CI: 0.74-0.92) lower risk while HPFS men experienced a 21% (95% CI: 0.66-0.96) lower CVD risk compared to those who consumed <1 serving/month. Regular yogurt consumers with higher DASH diet scores had 16% (95% CI: 0.73-0.96) and 30% (95% CI: 0.57-0.85) CVD risk reductions in the 2 cohorts, respectively.

CONCLUSION

Hypertensive men and women who consumed ≥2 servings/week of yogurt, especially in the context of a healthy diet, were at lower risk for developing CVD.

The Consumption of Dairy Products Is Associated with Reduced Risks of Obesity and Metabolic Syndrome in Korean Women but not in Men

We aimed to investigate the association between dairy product consumption and the risk of obesity and metabolic syndrome (MetS) in Korean adults. Data from 13,692 Korean adults aged ≥19 years from the KNHANES 2010–2013 were used. The study participants were divided into three groups according to the serving size of dairy products they consumed based on a single 24-h recall. About 58% of the Korean adults did not consume any dairy products in one day. In both the sexes, only those who adhered to the recommendation for dairy products (≥1 serving/day) achieved the daily requirement of calcium. Women who consumed ≥1 serving/day of dairy products had lower risks of obesity (body mass index ≥ 25 kg/m²) (adjusted odds ratio (AOR), 0.77; 95% confidence interval (CI), 0.66–0.89; p for trend < 0.01) and MetS (AOR, 0.67; 95% CI, 0.56–0.80; p for trend < 0.01) than women who did not consume dairy products. However, these significant associations were not observed in men. In conclusion, consuming ≥ 1 serving/day of dairy products could be an easy and efficient strategy for meeting daily calcium requirement as well as lowering risks of obesity and MetS among Korean women.

Dairy consumption, systolic blood pressure, and risk of hypertension: Mendelian randomization study

Objective To examine whether previous observed inverse associations of dairy intake with systolic blood pressure and risk of hypertension were causal.Design Mendelian randomization study using the single nucleotide polymorphism rs4988235 related to lactase persistence as an instrumental variable.Setting CHARGE (Cohorts for Heart and Aging Research in Genomic Epidemiology) Consortium.Participants Data from 22 studies with 171 213 participants, and an additional 10 published prospective studies with 26 119 participants included in the observational analysis.Main outcome measures The instrumental variable estimation was conducted using the ratio of coefficients approach. Using meta-analysis, an additional eight published randomized clinical trials on the association of dairy consumption with systolic blood pressure were summarized.Results Compared with the CC genotype (CC is associated with complete lactase deficiency), the CT/TT genotype (TT is associated with lactose persistence, and CT is associated with certain lactase deficiency) of LCT-13910 (lactase persistence gene) rs4988235 was associated with higher dairy consumption (0.23 (about 55 g/day), 95% confidence interval 0.17 to 0.29) serving/day; P<0.001) and was not associated with systolic blood pressure (0.31, 95% confidence interval -0.05 to 0.68 mm Hg; P=0.09) or risk of hypertension (odds ratio 1.01, 95% confidence interval 0.97 to 1.05; P=0.27). Using LCT-13910 rs4988235 as the instrumental variable, genetically determined dairy consumption was not associated with systolic blood pressure (β=1.35, 95% confidence interval -0.28 to 2.97 mm Hg for each serving/day) or risk of hypertension (odds ratio 1.04, 0.88 to 1.24). Moreover, meta-analysis of the published clinical trials showed that higher dairy intake has no significant effect on change in systolic blood pressure for interventions over one month to 12 months (intervention compared with control groups: β=-0.21, 95% confidence interval -0.98 to 0.57 mm Hg). In observational analysis, each serving/day increase in dairy consumption was associated with -0.11 (95% confidence interval -0.20 to -0.02 mm Hg; P=0.02) lower systolic blood pressure but not risk of hypertension (odds ratio 0.98, 0.97 to 1.00; P=0.11).Conclusion The weak inverse association between dairy intake and systolic blood pressure in observational studies was not supported by a comprehensive instrumental variable analysis and systematic review of existing clinical trials.

Low dairy calcium intake is associated with overweight and elevated blood pressure in Polish adults, notably in premenopausal women

OBJECTIVE

Dietary Ca is now being recognized to play an important role not only in skeletal integrity, but also in the regulation of energy and metabolism. The aim of the present study was to estimate the relationship of dairy Ca intake with BMI and blood pressure (BP) in a sample derived from the Polish population.

DESIGN

Ca intake was calculated from an interviewer-administered semi-quantitative FFQ. BMI was calculated from measured weight and height, and BP was measured by a physician.

SETTING

Cross-sectional epidemiological study on osteoporosis risk factors in Poland.

SUBJECTS

Randomly selected healthy adult persons (n 1259; 750 women and 509 men).

RESULTS

Dairy Ca intake was significantly lower in individuals with overweight/obesity (BMI≥25·00 kg/m2) and/or with elevated BP (systolic/diastolic ≥140/≥90 mmHg) than in those with normal body mass and BP, respectively. Ca intake was negatively correlated with BMI (r=-0·12, P<0·001), systolic BP (r=-0·11, P<0·001) and diastolic BP (r=-0·08, P<0·01). Daily dairy Ca intake below 1000 mg was a predictor for BMI≥25·0 kg/m2 (OR=1·44, P<0·005). This relationship was stronger in women, particularly premenopausal women.

CONCLUSIONS

The obtained results indicate the role of low dairy Ca intake in the development of obesity and hypertension, notably in premenopausal women.

Dairy food products: good or bad for cardiometabolic disease?

Prevalence of type 2 diabetes mellitus (T2DM) is rapidly increasingly and is a key risk for CVD development, now recognised as the leading cause of death globally. Dietary strategies to reduce CVD development include reduction of saturated fat intake. Milk and dairy products are the largest contributors to dietary saturated fats in the UK and reduced consumption is often recommended as a strategy for risk reduction. However, overall evidence from prospective cohort studies does not confirm a detrimental association between dairy product consumption and CVD risk. The present review critically evaluates the current evidence on the association between milk and dairy products and risk of CVD, T2DM and the metabolic syndrome (collectively, cardiometabolic disease). The effects of total and individual dairy foods on cardiometabolic risk factors and new information on the effects of the food matrix on reducing fat digestion are also reviewed. It is concluded that a policy to lower SFA intake by reducing dairy food consumption to reduce cardiometabolic disease risk is likely to have limited or possibly negative effects. There remain many uncertainties, including differential effects of different dairy products and those of differing fat content. Focused and suitably designed and powered studies are needed to provide clearer evidence not only of the mechanisms involved, but how they may be beneficially influenced during milk production and processing.

Examining associations between dietary patterns and metabolic CVD risk factors: a novel use of structural equation modelling

The association between dietary patterns and metabolic cardiovascular risk factors has long been addressed but there is a lack of evidence towards the effects of the overall diet on the complex net of biological inter-relationships between risk factors. This study aimed to derive dietary patterns and examine their associations with metabolic cardiovascular risk factors following a theoretic model for the relationship between them. Participants included 417 adults of both sexes, enrolled to the cross-sectional population-based study performed in Brazil. Body weight, waist circumference, high-sensitivity C-reactive protein, blood pressure, total cholesterol:HDL-cholesterol ratio, TAG:HDL-cholesterol ratio, fasting plasma glucose and serum leptin were evaluated. Food consumption was assessed by two non-consecutive 24-h dietary recalls adjusted for the within-person variation of intake. A total of three dietary patterns were derived by exploratory structural equation modelling: 'Traditional', 'Prudent' and 'Modern'. The 'Traditional' pattern had a negative and direct effect on obesity indicators (serum LEP, body weight and waist circumference) and negative indirect effects on total cholesterol:HDL-cholesterol ratio, TAG:HDL-cholesterol ratio and fasting plasma glucose. The 'Prudent' pattern had a negative and direct effect on systolic blood pressure. No association was observed for the 'Modern' pattern and metabolic risk factors. In conclusion, the 'Traditional' and 'Prudent' dietary patterns were negatively associated with metabolic cardiovascular risk factors among Brazilian adults. Their apparent protective effects against obesity and high blood pressure may be important non-pharmacological strategies for the prevention and control of obesity-related metabolic disorders and CVD.

New perspectives on dairy and cardiovascular health

CVD are the leading cause of mortality and morbidity worldwide. One of the key dietary recommendations for CVD prevention is reduction of saturated fat intake. Yet, despite milk and dairy foods contributing on average 27 % of saturated fat intake in the UK diet, evidence from prospective cohort studies does not support a detrimental effect of milk and dairy foods on risk of CVD. The present paper provides a brief overview of the role of milk and dairy products in the diets of UK adults, and will summarise the evidence in relation to the effects of milk and dairy consumption on CVD risk factors and mortality. The majority of prospective studies and meta-analyses examining the relationship between milk and dairy product consumption and risk of CVD show that milk and dairy products, excluding butter, are not associated with detrimental effects on CVD mortality or risk biomarkers that include serum LDL-cholesterol. In addition, there is increasing evidence that milk and dairy products are associated with lower blood pressure and arterial stiffness. These apparent benefits of milk and dairy foods have been attributed to their unique nutritional composition, and suggest that the elimination of milk and dairy may not be the optimum strategy for CVD risk reduction.

Protein intake in relation to risk of hypertension and microalbuminuria in patients with type 1 diabetes: the EURODIAB Prospective Complications Study

BACKGROUND

A beneficial association between dietary protein intake (especially from plant sources) with incident hypertension, being strongly correlated to microalbuminuria, has been suggested in healthy populations. Evidence from diabetic populations, in which the prevalence of these diseases is high, is lacking. We examined the associations of total, animal and plant protein intake with incident hypertension (n = 1319) and microalbuminuria (n = 1045) in patients from 16 European countries with type 1 diabetes from the clinic-based EURODIAB Prospective Complications study.

METHODS

Odds ratios (OR) with 95% confidence intervals (CI) for incident hypertension after 7 years of follow-up were calculated in tertiles of protein intake (energy%) with adjustments for age, sex, diabetes duration, HbA1c, BMI, physical activity, smoking, alcohol, total energy, total fat and carbohydrate intake.

RESULTS

After adjustment for potential confounders, total, animal and plant protein intakes were not related to incident hypertension (298 cases). OR's (95% CI) across increasing tertiles of total protein were 1.00 (ref), 0.86 (0.60-1.25) and 0.91 (0.59-1.43). Furthermore, no relation was observed with incident microalbuminuria (135 cases), with ORs (95% CI) across increasing tertiles of total protein being 1.00 (ref), 0.88 (0.53-1.48) and 1.08 (0.57-2.04).

CONCLUSION

Results from our study did not provide evidence that a protein intake commonly consumed by European patients with type 1 diabetes is associated with incident hypertension or microalbuminuria. Prospective studies with more detailed information on dietary intake (including mineral intake) are needed to confirm these findings, and to investigate the impact on vascular and renal complications of a long-term very high protein intake in patients with type 1 diabetes.

Effects of low-fat dairy intake on blood pressure, endothelial function, and lipoprotein lipids in subjects with prehypertension or stage 1 hypertension

OBJECTIVE

This randomized crossover trial assessed the effects of 5 weeks of consuming low-fat dairy (one serving/day each of 1% fluid milk, low-fat cheese, and low-fat yogurt) versus nondairy products (one serving/day each of apple juice, pretzels, and cereal bar) on systolic and diastolic blood pressures (SBP and DBP), vascular function (reactive hyperemia index [RHI] and augmentation index), and plasma lipids.

METHODS

Patients were 62 men and women (mean age 54.5 years, body mass index 29.2 kg/m(2)) with prehypertension or stage 1 hypertension (mean resting SBP/DBP 129.8 mmHg/80.8 mmHg) while not receiving antihypertensive medications. A standard breakfast meal challenge including two servings of study products was administered at the end of each treatment period.

RESULTS

Dairy and nondairy treatments did not produce significantly different mean SBP or DBP in the resting postprandial state or from premeal to 3.5 hours postmeal (SBP, 126.3 mmHg versus 124.9 mmHg; DBP, 76.5 mmHg versus 75.7 mmHg), premeal (2.35 versus 2.20) or 2 hours postmeal (2.33 versus 2.30) RHI, and premeal (22.5 versus 23.8) or 2 hours postmeal (12.4 versus 13.2) augmentation index. Among subjects with endothelial dysfunction (RHI ≤ 1.67; n = 14) during the control treatment, premeal RHI was significantly higher in the dairy versus nondairy condition (2.32 versus 1.50, P = 0.002). Fasting lipoprotein lipid values were not significantly different between treatments overall, or in subgroup analyses.

CONCLUSION

No significant effects of consuming low-fat dairy products, compared with low-fat nondairy products, were observed for blood pressures, measures of vascular function, or lipid variables in the overall sample, but results from subgroup analyses were consistent with the hypothesis that dairy foods might improve RHI in those with endothelial dysfunction.

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

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

Dairy and blood pressure: a fresh look at the evidence

The Dietary Guidelines for Americans, 2010 indicated there is moderate evidence for an association between the consumption of dairy foods and lower blood pressure in adults; however, it also stated that more evidence was needed, especially in clinical trials, to fully delineate a causal relationship. The purpose of this review is to provide background by examining the historical literature and the evidence reviewed by the 2010 Dietary Guidelines Advisory Committee, to examine the gaps in knowledge indicated by that committee, and to determine if recently published evidence is sufficient to elucidate or dismiss an association between dairy foods and blood pressure maintenance. Examination of the newly published literature, together with evaluation of the evidence as a whole, shows that the preponderance of evidence indicates dairy foods are beneficially associated with blood pressure; however, additional research is necessary to identify the mechanism of action of dairy foods. New evidence should come from carefully designed clinical trials that examine not only blood pressure outcomes but also the ability of dairy foods to affect the vasculature.

Diet and blood pressure in 18-74-year-old adults: the French Nutrition and Health Survey (ENNS, 2006-2007)

OBJECTIVE

Dietary recommendations to reduce blood pressure (BP) have been widely disseminated. We investigated associations between dietary intake and BP in a national sample of adults living in France.

METHODS

The survey included 1968 18-74-year-old participants in the French Nutrition and Health Survey (Etude Nationale Nutrition Santé), a cross-sectional national multistage sampling study. Dietary intake and SBP and DBP were assessed using three 24-h recalls and three measurements, respectively. Mean dietary intake was compared across BP categories: previously diagnosed hypertensive and among undiagnosed optimal (SBP <120  mmHg and DBP <80  mmHg), intermediate and high (SBP ≥140  mmHg and/or DBP ≥90  mmHg) BP participants. After exclusion of previously diagnosed hypertensive participants, linear regressions were also carried out between dietary intake and SBP and DBP.

RESULTS

Eating habits of previously diagnosed hypertensive participants were not different from those of undiagnosed high BP participants, except higher milk consumption (P = 0.03) and lower seafood and alcohol intake (P < 0.03 and P = 0.002, respectively) in previously diagnosed hypertensive. After exclusion of them, dairy products (milk especially), fruit and vegetables, fiber and whole-grain food consumption were inversely and linearly associated with SBP (P < 0.04), whereas alcohol intake was positively associated with SBP (P < 10) and DBP (P = 0.005). Modification effect of sex was observed for saturated fatty acids intake (positive association with DPB in women) and calcium (negative association with SBP in men).

CONCLUSION

Adherence to nutritional recommendations still needs to be improved in hypertensive adults even if they are aware of their condition. In the rest of the population, proper habits regarding milk, fruit and vegetables, fiber and alcohol should decrease the risk of hypertension onset.

Does calcium intake affect cardiovascular risk factors and/or events?

Dietary intervention is an important approach in the prevention of cardiovascular disease. Over the last decade, some studies have suggested that a calcium-rich diet could help to control body weight, with anti-obesity effects. The potential mechanism underlying the impact of calcium on body fat has been investigated, but it is not fully understood. Recent evidence has also suggested that a calcium-rich diet could have beneficial effects on other cardiovascular risk factors, such as insulin resistance, dyslipidemia, hypertension and inflammatory states. In a series of studies, it was observed that a high intake of milk and/or dairy products (the main sources of dietary calcium) is associated with a reduction in the relative risk of cardiovascular disease. However, a few studies suggest that supplemental calcium (mainly calcium carbonate or citrate) may be associated with an increased risk of cardiovascular events. This review will discuss the available evidence regarding the relationship between calcium intake (dietary and supplemental) and different cardiovascular risk factors and/or events.

Vegetarian diets and blood pressure among white subjects: results from the Adventist Health Study-2 (AHS-2)

OBJECTIVE

Previous work studying vegetarians has often found that they have lower blood pressure (BP). Reasons may include their lower BMI and higher intake levels of fruit and vegetables. Here we seek to extend this evidence in a geographically diverse population containing vegans, lacto-ovo vegetarians and omnivores.

DESIGN

Data are analysed from a calibration sub-study of the Adventist Health Study-2 (AHS-2) cohort who attended clinics and provided validated FFQ. Criteria were established for vegan, lacto-ovo vegetarian, partial vegetarian and omnivorous dietary patterns.

SETTING

Clinics were conducted at churches across the USA and Canada. Dietary data were gathered by mailed questionnaire.

SUBJECTS

Five hundred white subjects representing the AHS-2 cohort.

RESULTS

Covariate-adjusted regression analyses demonstrated that the vegan vegetarians had lower systolic and diastolic BP (mmHg) than omnivorous Adventists (β = -6.8, P < 0.05 and β = -6.9, P < 0.001). Findings for lacto-ovo vegetarians (β = -9.1, P < 0.001 and β = -5.8, P < 0.001) were similar. The vegetarians (mainly the vegans) were also less likely to be using antihypertensive medications. Defining hypertension as systolic BP > 139 mmHg or diastolic BP > 89 mmHg or use of antihypertensive medications, the odds ratio of hypertension compared with omnivores was 0.37 (95 % CI 0.19, 0.74), 0.57 (95 % CI 0.36, 0.92) and 0.92 (95 % CI 0.50, 1.70), respectively, for vegans, lacto-ovo vegetarians and partial vegetarians. Effects were reduced after adjustment for BMI.

CONCLUSIONS

We conclude from this relatively large study that vegetarians, especially vegans, with otherwise diverse characteristics but stable diets, do have lower systolic and diastolic BP and less hypertension than omnivores. This is only partly due to their lower body mass.

High dietary sodium intake among young children in Vancouver, British Columbia

OBJECTIVE

To determine the intake distribution and food sources of sodium among young children.

METHODS

Dietary intake was determined for 190 children, 16 months to 6 years of age, using a food frequency questionnaire completed by interviewing a parent. Dietary intake of all nutrients, including dietary sodium, was analyzed. The major food sources of sodium were assessed by grouping foods into categories based on Canada's Food Guide, with subsequent subdivision into food type categories.

RESULTS

Dietary sodium intakes were skewed, with a median intake of 2021 mg/d and 5th-95th percentile range of 888-3975 mg/d. The sodium intake of 91.6% of children was above the recommended 1000 or 1200 mg/d for children 1-3 or 3-6 years, respectively, and 85% and 54% had intakes above the tolerable upper limits of 1500 and 1900 mg/d, respectively. The 5 food sources providing the highest amount of sodium were soups, processed/fast foods, dairy products, breads, and processed meats.

CONCLUSION

Children are vulnerable to high sodium intake as a result of their food patterns and the high sodium content of these foods. This report demonstrates that Canadian children have high sodium intakes. Knowledge of feeding practices involving high-sodium foods can assist parents and caregivers in reducing the high sodium intake of young children.

Milk in the diet: good or bad for vascular disease?

CVD still represent the greatest cause of death and disease burden in Europe and there remains uncertainty whether or not diets rich in milk and/or dairy products affect CVD risk. This paper reviews current evidence on this from prospective studies and the role of serum lipids and blood pressure as markers of CVD risk with such diets. Also the potential of animal nutrition-based approaches aimed at reducing CVD risk from consumption of milk and dairy products is outlined. Briefly, the evidence from prospective studies indicates that increased consumption of milk does not result in increased CVD risk and may give some long-term benefits, although few studies relate specifically to cheese and butter and more information on the relationship between milk/dairy product consumption and dementia is needed. Recent data suggest that the SFA in dairy products may be less of a risk factor than previously thought; although this is based on serum cholesterol responses which taken in isolation may be misleading. Milk and some dairy products have counterbalancing effects by reducing blood pressure and possibly BMI control. Despite this, animal nutrition strategies to replace some SFA in milk with cis-MUFA or cis-PUFA are extensive and intuitively beneficial, although this remains largely unproven, especially for milk. There is an urgent need for robust intervention studies to evaluate such milk-fat modifications using holistic markers of CVD risk including central arterial stiffness.

Self-perceived lactose intolerance results in lower intakes of calcium and dairy foods and is associated with hypertension and diabetes in adults

BACKGROUND

Self-perceived lactose intolerance may result in adverse dietary modifications; thus, more studies are needed to understand the prevalence of self-perceived lactose intolerance and how it relates to calcium intake and selected health conditions.

OBJECTIVE

The objective was to examine the effects of self-perceived lactose intolerance as it relates to calcium intake and specific health problems that have been attributed to reduced intakes of calcium and dairy foods in a nationally representative multiethnic sample of adults.

DESIGN

This was a cross-sectional study in a national sample of 3452 adults. The relation between self-perceived lactose intolerance, calcium intakes, and physician-diagnosed health conditions was analyzed by using linear regression analyses.

RESULTS

Of the total sample, 12.3% of respondents perceived themselves to be lactose intolerant. The age-adjusted prevalence of self-perceived lactose intolerance was 7.8% for non-Hispanic whites, 20.1% for non-Hispanic blacks, and 8.8% for Hispanics. Respondents with self-perceived lactose intolerance had significantly lower (P < 0.05) average daily calcium intakes from dairy foods than did those without self-perceived lactose intolerance. A significantly higher (P < 0.05) percentage of respondents with self-perceived lactose intolerance than of respondents without self-perceived lactose intolerance reported having physician-diagnosed diabetes and hypertension. The odds of self-reported physician-diagnosed diabetes or hypertension decreased by factors of 0.70 and 0.60, respectively, for a 1000-mg increase in calcium intake from dairy foods per day.

CONCLUSIONS

Self-perceived lactose-intolerant respondents had a significantly lower calcium intake from dairy foods and reported having a significantly higher rate of physician-diagnosed diabetes and hypertension.

Dairy Consumption, Blood Pressure, and Risk of Hypertension: An Evidence-Based Review of Recent Literature

Hypertension is a major risk factor for development of stroke, coronary heart disease, heart failure, and end-stage renal disease. In a systematic review of the evidence published from 2004 to 2009, the 2010 Dietary Guidelines Advisory Committee (DGAC) concluded there was moderate evidence of an inverse relationship between the intake of milk and milk products (dairy) and blood pressure. This review synthesizes results from studies published over the past year on the relationship between dairy intake, blood pressure, and hypertension risk. The influence of dairy micronutrients including calcium, vitamin D, potassium, and phosphorous on blood pressure and incident hypertension is examined. Emerging research on bioactive dairy peptides is also reviewed. Lastly, recent evidence on effects of dairy fat content on blood pressure and hypertension risk, and the impact of inclusion of low-fat dairy in dietary patterns is also investigated.

Dietary protein and risk of hypertension in a Dutch older population: the Rotterdam study

BACKGROUND

Several observational studies suggest an inverse association of protein with blood pressure (BP). However, little is known about the role of dietary protein from specific sources in BP.

METHOD

We examined the relation between several types of dietary protein (total, plant, animal, dairy, meat, grain, fish, soy, and nut) and incident hypertension in 2241 participants from the Rotterdam Study, aged at least 55 years, who were free of hypertension at baseline. Hazard ratios, with 95% confidence intervals (CIs), for incident hypertension during 6 years of follow-up were obtained per standard deviation (SD) of energy-adjusted intake of protein. Hazard ratios were adjusted for age, sex, body mass index (BMI), baseline systolic blood pressure (SBP) smoking, educational level, alcohol, intake of carbohydrates, other nutrients, and other types of protein (if applicable). We conducted stratified analyses by age (cut-off 70 years), sex, and BMI (cut-off 25 kg/m).

RESULTS

The risk of hypertension in the total cohort (1113 cases) was not related to intake of total protein or types of protein (all hazard ratios ∼1.00 per SD). Sex and BMI did not significantly modify the associations of dietary protein with hypertension. In 559 participants aged at least 70 years, the intake of animal protein was positively related to risk of hypertension (hazard ratio 1.37 per SD, 95% CI 1.09-1.72). For participants aged below 70 years no association was found (hazard ratio 0.92, 95% CI 0.81-1.06).

CONCLUSION

Total dietary protein or types of protein are not related to incident hypertension in this older population. In the more aged, however, high intake of animal protein may increase the risk of hypertension, which warrants further investigation.

A systematic review and meta-analysis of elevated blood pressure and consumption of dairy foods

Hypertension is a public health priority in developed countries and worldwide, and is strongly associated with increased risk and progression of cardiovascular and renal diseases. A systematic review and meta-analysis were conducted to examine the association between dairy food intake during adulthood and the development of elevated blood pressure (EBP), specifically comparing the association of EBP with consumption of low-fat dairy foods versus high-fat dairy foods, as well as cheese versus fluid dairy foods (milk or yogurt). Seven databases were searched and five cohort studies selected for inclusion, involving nearly 45,000 subjects and 11,500 cases of EBP. Meta-analysis of consumption of dairy foods and EBP in adults gave a relative risk (RR) of 0.87 (95% confidence interval (CI) 0.81-0.94). Separation of high- and low-fat dairy foods, however, indicated a significant association with low-fat dairy foods only (RR of 0.84 (95% CI 0.74-0.95)). Additional analyses showed no association between EBP and cheese, although fluid dairy foods were significantly associated with a reduced development in EBP (RR of 0.92 (95% CI 0.87-0.98)). Little heterogeneity was observed among the data presented. This meta-analysis supports the inverse association between low-fat dairy foods and fluid dairy foods and risk of EBP. Understanding these relationships can aid in the development of public health messages involving dairy foods, and supports current recommendations.

Current in vitro testing of bioactive peptides is not valuable

Dietary peptides have been suggested to possess biological activity in vivo and could affect cardiovascular disease parameters, based on data derived from in vitro experiments. Isolated peptides are often tested in in vitro cellular assays or on heterologously expressed molecular target proteins. The stimulatory or inhibitory effect on target proteins in vitro has often been used as the justification to test these compounds directly in vivo. Unfortunately, this research approach has an inherent flaw. It neglects the poor absorption, distribution, metabolism, and excretion (ADME) properties of peptides resulting in low peptide bioavailability. Because peptides are prone to extensive hydrolysis in the gastrointestinal tract by stomach, small intestinal, and brush border peptidases, most of them do not reach the absorption stage in the duodenum and jejunum. Therefore, a valid research approach should include the demonstration of stability of the peptide toward luminal and brush border peptidases and evaluate its ADME properties. Surprisingly, only very few animal and human studies determined absolute concentrations and kinetics of bioactive peptides. These studies have shown the presence of selected peptides in plasma samples at pico- and nanomolar concentrations with fast elimination kinetics in the minute range. For the correct interpretation of results, it is advised that researchers refer to the data currently available concerning bioavailability and ADME properties in humans. Two mandatory criteria for future in vitro studies investigating potential biological activities of peptides should be using physiologically relevant concentrations and times.

Dairy products and metabolic effects in overweight men and women: results from a 6-mo intervention study

BACKGROUND

Some epidemiologic studies have suggested inverse relations between intake of dairy products and components of the metabolic syndrome.

OBJECTIVE

The objective was to investigate the effects of an increased intake of dairy products in persons with a habitually low intake on body composition and factors related to the metabolic syndrome.

DESIGN

Middle-aged overweight subjects (n = 121) with traits of the metabolic syndrome were recruited in Finland, Norway, and Sweden and randomly assigned into milk or control groups. The milk group was instructed to consume 3-5 portions of dairy products daily. The control group maintained their habitual diet. Clinical investigations were conducted on admission and after 6 mo.

RESULTS

There were no significant differences between changes in body weight or body composition, blood pressure, markers of inflammation, endothelial function, adiponectin, or oxidative stress in the milk and the control groups. There was a modest unfavorable increase in serum cholesterol concentrations in the milk group (P = 0.043). Among participants with a low calcium intake at baseline (<700 mg/d), there was a significant treatment effect for waist circumference (P = 0.003) and sagittal abdominal diameter (P = 0.034). When the sexes were analyzed separately, leptin increased (P = 0.045) and vascular cell adhesion molecule-1 decreased (P = 0.001) in women in the milk group.

CONCLUSIONS

This study gives no clear support to the hypothesis that a moderately increased intake of dairy products beneficially affects aspects of the metabolic syndrome. The apparently positive effects on waist circumference and sagittal abdominal diameter in subjects with a low calcium intake suggest a possible threshold in relation to effects on body composition.

Milk products, insulin resistance syndrome and type 2 diabetes

A growing body of evidence suggests an inverse relationship between calcium and vitamin D status and dairy food intake and the development of the insulin resistance syndrome (IRS) and type 2 diabetes mellitus (t2DM). Observational studies show a consistent inverse association between dairy intake and the prevalence of IRS and t2DM. In a systematic review of the observational evidence, the odds for developing the IRS was 0.71 (95% CI, 0,57-0.89) for the highest dairy intake (3-4 servings/d) vs. the lowest intake (0.9-1.7 servings/d). Few interventional studies have been conducted to evaluate the effects of dairy food intake on the management of prevention of IRS or t2DM. Intervention studies that have examined the independent effects of dairy intake on specific metabolic components of the IRS including blood pressure and obesigenic parameters have shown favorable effects that support the observational findings albeit the results have been less consistent. Many metabolic and dietary factors appear to influence the degree to which dairy affects IRS metabolic parameters including calcium and vitamin D intake status, BMI, ethnicity and age. Overall, the intake of low-fat dairy products is a feature of a healthy dietary pattern which has been shown to contribute to a significant extent to the prevention of IRS.

Milk products, dietary patterns and blood pressure management

High blood pressure (BP) is a major risk factor for heart disease, stroke, congestive heart failure, and kidney disease. Inverse associations between dairy product consumption and systolic blood pressure (SBP) and diastolic blood pressure (DBP) have been observed in cross-sectional studies; some studies, however, have reported an inverse association with only one BP parameter, predominantly SBP. Randomized clinical trials examining the effect of calcium and the combination of calcium, potassium and magnesium provide evidence for causality. In these studies, reductions in BP were generally modest (-1.27 to -4.6 mmHg for SBP, and -0.24 to -3.8 mmHg for DBP). Dairy nutrients, most notably calcium, potassium and magnesium, have been shown to have a blood pressure lowering effect. A low calcium intake increases intracellular calcium concentrations which increases 1,25-dihydroxyvitamin D(3) and parathyroid hormone (PTH), causing calcium influx into vascular smooth muscle cells, resulting in greater vascular resistance. New research indicates that dairy peptides may act as angiotensin converting enzyme (ACE) inhibitors, thereby inhibiting the renin angiotensin system with consequent vasodilation. A growing evidence base shows that dairy product consumption is involved in the regulation of BP. Consequently, inclusion of dairy products in a heart healthy diet is an important focal point to attain BP benefits.

Inverse association between dairy intake and hypertension: the Rotterdam Study

BACKGROUND

Little is known about the effect of different types of dairy food products on the development of hypertension.

OBJECTIVE

The objective was to determine whether the incidence of hypertension in older Dutch subjects is associated with intake of dairy products.

DESIGN

We examined the relation between dairy intake and incident hypertension in 2245 participants of the Rotterdam Study aged > or =55 y with complete dietary and blood pressure data, who were free of hypertension at baseline (1990-1993). Blood pressure was reexamined in 1993-1995 and in 1997-1999. Hazard ratios (HRs) with 95% CIs for 2- and 6-y incidence of hypertension were obtained in quartiles of energy-adjusted dairy intake, with adjustment for age, sex, BMI, smoking, educational level, dietary factors, and intake of alcohol and total energy.

RESULTS

Risk of hypertension after 2 y of follow-up (664 incident cases) was inversely associated with dairy product intake. After adjustment for confounders, HRs (95% CIs) were 1.00, 0.82 (0.67, 1.02), 0.67 (0.54, 0.84), and 0.76 (0.61, 0.95) in consecutive quartiles of total dairy product intake (P for trend = 0.008). Corresponding HRs for low-fat dairy products were 1.00, 0.75 (0.60, 0.92), 0.77 (0.63, 0.96), and 0.69 (0.56, 0.86) (P for trend = 0.003). Analysis of specific types of dairy products showed an inverse association with milk and milk products (P for trend = 0.07) and no association with high-fat dairy or cheese (P > 0.6). After 6 y of follow-up (984 incident cases), the associations with hypertension were attenuated to risk reductions of approximately 20% for both total and low-fat dairy products between the extreme quartiles of intake (P for trend = 0.07 and 0.09, respectively).

CONCLUSION

Intake of low-fat dairy products may contribute to the prevention of hypertension at an older age.

Dairy intake, blood pressure, and incident hypertension in a general Dutch population

Diet and lifestyle are important for maintaining a healthy blood pressure (BP). The role of dairy in the prevention of hypertension, however, is not yet clear. We studied the relation of dairy intake with BP in 21,553 Dutch participants aged 20-65 y who did not use antihypertensive medication. In addition, the risk of hypertension was examined in 3454 of these participants with a 5-y follow-up. Dairy consumption was assessed at baseline (1993-1997) using a semiquantitative FFQ that included 178 foods and beverages. Baseline BP and odds ratios (OR) (95% CI) for incident hypertension were calculated in categories of energy-adjusted dairy intake with adjustment for age, sex, socioeconomic status, BMI, smoking, alcohol use, and dietary intakes. Participants had a median intake of 344 g/d (approximately 2.3 servings) for total dairy and 174 g/d (approximately 1.2 servings) for low-fat dairy. Mean BP was 120/76 mm Hg. Intake of total dairy, specific dairy groups (i.e. low-fat, high-fat, fermented) and dairy products (i.e. cheese, yogurt) were not consistently related to BP. Of 3454 participants who were followed, 713 developed hypertension. The risk of hypertension tended to be inversely related to low-fat dairy intake, with multivariate OR (95% CI) of 1.00, 0.78 (0.61, 1.00), 0.81 (0.63, 1.03), and 0.82 (0.64, 1.06; P-trend: 0.24) in consecutive quartiles. We conclude that variations in BP in a general middle-aged Dutch population cannot be explained by overall dairy intake. A beneficial effect of low-fat dairy on risk of hypertension, however, cannot be excluded, which warrants further investigation in prospective population-based studies.

Long-term effect of calcium-vitamin D(3) fortified milk on blood pressure and serum lipid concentrations in healthy older men

BACKGROUND/OBJECTIVES

Some epidemiological and clinical studies have shown that increased dairy consumption or calcium and/or vitamin D supplementation can have a beneficial effect on blood pressure, and lipid and lipoprotein concentrations. The aim of this study was to assess the long-term effects of calcium-vitamin D(3) fortified milk on blood pressure and lipid-lipoprotein concentrations in community-dwelling older men.

SUBJECTS/METHODS

This is a substudy of a 2-year randomized controlled trial in which 167 men aged >50 years were assigned to receive either 400 ml per day of reduced fat (approximately 1%) milk fortified with approximately 1000 mg of calcium and 800 IU of vitamin D(3) or to a control group receiving no additional fortified milk. Weight, blood pressure, lipid and lipoprotein concentrations were measured every 6 months. Participants on lipid-lowering (n=32) or antihypertensive medication (n=39) were included, but those who commenced, increased or decreased their medication throughout the intervention were excluded (n=27).

RESULTS

In the 140 men included in this study (milk, n=73; control, n=67), there were no significant effects of the calcium-vitamin D(3) fortified milk on weight, systolic or diastolic blood pressure, total cholesterol, high-density lipoprotein or low-density lipoprotein cholesterol or triglyceride concentrations at any time throughout the intervention. Similar results were observed after excluding men taking antihypertensive or lipid-lowering medication or limiting the analysis to those with baseline calcium intakes <1000 mg per day and/or with hypovitaminosis D (25(OH)D <75 nmol/l).

CONCLUSIONS

Supplementation with reduced-fat calcium-vitamin D(3) fortified milk did not have a beneficial (nor detrimental) effect on blood pressure, lipid or lipoprotein concentrations in healthy community-dwelling older men.

The impact of dairy product consumption on nutrient adequacy and weight of Head Start mothers

OBJECTIVE

To assess the relationship of dairy product consumption on diet quality and weight of low-income women.

SETTING

Head Start centres in Texas and Alabama, USA.

DESIGN

Cross-sectional study. Women were divided into dairy consumption groups: < or =1, >1 to < or =2 and >2 servings/d. Nutrient intake/diet quality was determined by calculating the percentage meeting the Estimated Average Requirement, guidelines for fat and added sugar, and Mean Adequacy Ratio (MAR). Mean BMI was compared for the dairy consumption groups.

SUBJECTS

Mothers with children in Head Start; 609 African-Americans (43 %), Hispanic-Americans (32 %) and European-Americans (24 %).

RESULTS

Fifteen per cent of participants consumed >2 servings of dairy products and 57 % consumed < or =1 serving of dairy daily. Intakes of protein, vitamin D, riboflavin, P, Ca, K, Mg and Zn were significantly higher in those consuming >2 servings/d. Total SFA were higher and added sugars were lower in those consuming >2 servings of dairy products daily compared with those consuming < or =2 servings/d. Forty-one per cent of women consuming >2 servings of dairy daily had MAR scores under 85 compared with 94 % consuming < or =1 serving/d. Mean BMI was 30.36 kg/m2; there was no association between BMI and dairy product consumption.

CONCLUSIONS

Consumption of dairy products was low and was not associated with BMI in this low-income population. Higher levels of dairy product consumption were associated with higher MAR scores and improved intakes of Ca, K and Mg, which have been identified as shortfall nutrients in the diets of adults.