Associations between Dietary Patterns and Blood Pressure in a Clinical Sample of Overweight Adults

Diet to Stop Hypertension: Should Fats be Included?

PURPOSE OF REVIEW

International guidelines emphasize advice to incorporate dietary measures for the prevention and in the management of hypertension. Current data show that modest reductions in weight can have an impact on blood pressure. Reducing salt and marine oils have also shown consistent benefit in reducing blood pressure. Whether other dietary constituents, in particular the amount and type of fat that play important roles in cardiovascular prevention, influence blood pressure sufficiently to be included in the management of hypertension is less certain. In this review, we provide a summary of the most recent findings, with a focus on dietary patterns, fats and other nutrients and their impact on blood pressure and hypertension.

RECENT FINDINGS

Since reducing salt consumption is an established recommendation only corollary dietary advice is subject to the current review. Population studies that have included reliable evaluation of fat intake have indicated almost consistently blood pressure lowering with consumption of marine oils and fats. Results with vegetable oils are inconclusive. However dietary patterns that included total fat reduction and changes in the nature of vegetable fats/oils have suggested beneficial effects on blood pressure. Plant-based foods, dairy foods and yoghurt particularly, may also lower blood pressure irrespective of fat content. Total fat consumption is not directly associated with blood pressure except when it is part of a weight loss diet. Consumption of marine oils has mostly shown moderate blood pressure lowering and possibly greatest effect with docosahexaenoic acid-rich oil.

Novel Lines of Research on the Environmental and Human Health Impacts of Nut Consumption

Nuts have formed part of human diets throughout the ages. In recent decades, research has shown they are key foods in dietary patterns associated with lower chronic disease risk. The current state of climate change, however, has introduced an imperative to review the impact of dietary patterns on the environment with a shift to plant-based diets. Nuts emerge as a significant source of protein in plant-based diets and are a minimally processed and sustainable food. Research in this area is evolving to drive better production methods in varying climate conditions. Nevertheless, nut consumption remains an important contributor to human health. The mechanisms of action can be explained in terms of the nutrients they deliver. Studies of nut consumption have linked components such as monounsaturated fatty acids, plant omega-3 fatty acids, antioxidants, and plant sterols to improved lipoprotein profiles, lower blood pressure, and reduced cardiovascular disease risk. Preliminary research also indicates possible beneficial effects of nut consumption on reproductive health. In any case, the ultimate effects of foods on health are the results of multiple interactive factors, so where nuts fit within dietary patterns is a significant consideration for research translation. This has implications for research methodologies, including categorization within food groups and inclusion in Healthy Dietary Indices. The aim of this narrative review is to outline new focal points for investigation that examine the environmental and some novel human health impacts of nut consumption and discuss future directions for research.

Association of fish consumption with risk of all-cause and cardiovascular disease mortality: an 11-year follow-up of the Guangzhou Biobank Cohort Study

BACKGROUND

Whether fish consumption is associated with all-cause, cardiovascular (CVD), ischemic heart disease (IHD) and stroke mortality remains inconclusive. We examined the association of fish consumption with all-cause, cardiovascular (CVD), ischemic heart disease (IHD) and stroke mortality in older men and women in south China.

METHODS

A total of 18,215 participants including men and women without CVD at baseline (2003-2006) from Guangzhou Biobank Cohort Study (GBCS) were included and followed up till December 2017. Deaths were identified through record linkage with the Death Registry. Information on fish consumption was obtained using a food frequency questionnaire.

RESULTS

During an average follow-up of 11.4 (standard deviation = 2.1) years, 2,697 deaths occurred, including 917 total CVD, 397 IHD and 374 stroke deaths. After adjusting for potential confounders, compared with fish consumption of 0-3 servings/week (i.e., 0-21 g/day, one serving = 50 g), consumption of 4-6 servings/week (29-43 g/day) showed significantly lower risks of all-cause and CVD mortality (hazards ratio (HR) and 95% confidence interval (CI): 0.85 (0.76, 0.95) and 0.77 (0.64, 0.93), respectively), but the reduced risk of IHD mortality (HR (95% CI): 0.80 (0.60, 1.07)) was not significant. Consumption of 7-10 servings/week or higher showed no association with all-cause, CVD, IHD, and stroke mortality.

CONCLUSIONS

Moderate fish consumption of 4-6 servings/week (29-43 g/day) was associated with lower all-cause and CVD mortality risk. Our findings support the current general advice on regular fish consumption also in middle-aged and older adults.

The association between dietary patterns with severity of coronary artery stenosis, serum leptin-to-adiponectin ratio, and some related risk factors in patients with coronary artery disease

Background

This research aimed to investigate the association between dietary patterns with severity of coronary artery stenosis, serum leptin-to-adiponectin ratio, and some related risk factors in patients with coronary artery disease referred for coronary angiography.

Methods

This cross-sectional study was carried out on 191 men patients with known coronary disease aged 40-70 years whom were admitted to angiography ward of Ahvaz teaching hospital, Ahvaz, Iran. Dietary patterns were investigated using 161-item semi-quantitative food frequency questionnaire. Anthropometric indices; blood pressure; serum levels of adiponectin and leptin, blood levels of glucose, total cholesterol, HDL-C, LDL-C, and triglycerides were measured. Patients were categorized based on the severity of coronary artery disease [number of vessel involved-single (VD1), double (VD2), triple (VD3)].

Results

Three major dietary patterns were recognized using a factor analysis approach: western, healthy, and traditional patterns. Linear regression analysis demonstrated that there was a negative association between healthy dietary pattern with LDL-C, total cholesterol, and triglycerides. This dietary pattern was positively related to HDL-C. Both traditional and western dietary patterns were related to fasting blood glucose level and lipid profile. General obesity was positively associated with traditional and western dietary patterns. There was a positive relationship between central obesity with traditional and western dietary patterns, but a negative association was reported between the healthy dietary pattern and central obesity. Traditional and western dietary patterns demonstrated a significant positive relationship with serum leptin levels and ratio of L/A, and an inverse relationship with adiponectin. Healthy dietary pattern had a significant negative association with serum leptin levels and ratio of L/A. Healthy dietary pattern was negatively related to the severity of vessel stenosis. Patients in the third quartile of healthy dietary pattern were less likely to have vessel stenosis (OR = 43%, 95% CI: 0.07-0.87).

Conclusions

The findings show that adherence to a healthy dietary pattern was negatively associated with coronary artery stenosis and its related risk factors. However, adherence to western and traditional dietary patterns was positively related to coronary artery disease risk factors.

Urinary sodium-to-potassium ratio: a simple and useful indicator of diet quality in population-based studies

Background

Current evidence regarding the prognostic relevance of urinary sodium-to-potassium ratio (Na-to-K ratio), as an indicator of diet quality is limited. This study was conducted to investigate whether urinary Na-to-K ratio could be related to habitual dietary patterns, in a general population.

Methods

This study was conducted in the framework of the Tehran Lipid and Glucose Study (2014–2017) on 1864 adult men and women. Urinary Na and K concentrations were measured in the morning spot urine samples. Dietary intakes of the participants were assessed using a validated 147-item Food Frequency Questionnaire (FFQ) and major dietary patterns were obtained using principal component analysis. Mediterranean dietary pattern and Dietary Approaches to Stop Hypertension (DASH) score, were also calculated. Multivariable-adjusted linear regression was used to indicate association of dietary patterns and urinary Na-to-K ratio.

Results

Mean (± SD) age of participants was 43.7 ± 13.9 years and 47% were men. Mean (± SD) urinary Na, K and the ratio was 139 ± 41.0 and 57.9 ± 18.6 mmol/L, 2.40 ± 0.07, respectively. Higher urinary Na-to-K ratio (> 2.37 vs. < 1.49) was related to lower intakes of vegetables (282 vs. 321 g/day), low-fat dairy (228 vs. 260 g/day) and fruits (440 vs. 370 g/day). Western dietary pattern was related to higher urinary Na-to-K ratio (β = 0.06; 95% CI 0.01, 0.16). Traditional dietary pattern, Mediterranean and DASH diet scores were inversely associated with urinary Na-to-K ratio (β = − 0.14; 95% CI − 0.24, − 0.11, β = − 0.07; 95% CI − 0.09, − 0.01, β = − 0.12; 95% CI − 0.05, − 0.02, respectively).

Conclusions

Spot urinary Na-to-K ratio may be used as a simple and inexpensive method to monitor diet quality in population-based epidemiological studies.

Identifying Usual Food Choice Combinations With Walnuts: Analysis of a 2005-2015 Clinical Trial Cohort of Overweight and Obese Adults

Consumption of nuts has been associated with a range of favorable health outcomes. Evidence is now emerging to suggest that walnuts may also play an important role in supporting the consumption of a healthy dietary pattern. However, limited studies have explored how walnuts are eaten at different meal occasions. The aim of this study was to explore the food choices in relation to walnuts at meal occasions as reported by a sample of overweight and obese adult participants of weight loss clinical trials. Baseline usual food intake data were retrospectively pooled from four food-based clinical trials (n = 758). A nut-specific food composition database was applied to determine walnut consumption within the food intake data. The a priori algorithm of association rules was used to identify food choices associated with walnuts at different meal occasions using a nested hierarchical food group classification system. The proportion of participants who were consuming walnuts was 14.5% (n = 110). The median walnut intake was 5.14 (interquartile range, 1.10–11.45) g/d. A total of 128 food items containing walnuts were identified for walnut consumers. The proportion of participants who reported consuming unsalted raw walnut was 80.5% (n = 103). There were no identified patterns to food choices in relation to walnut at the breakfast, lunch, or dinner meal occasions. A total of 24 clusters of food choices related to walnuts were identified at others (meals). By applying a novel food composition database, the present study was able to map the precise combinations of foods associated with walnuts intakes at mealtimes using data mining. This study offers insights into the role of walnuts for the food choices of overweight adults and may support guidance and dietary behavior change strategies.

Beneficial Effects of Walnuts on Cognition and Brain Health

Oxidative stress and neuroinflammation have important roles in the aging process, mild cognitive impairment (MCI), Alzheimer’s disease (AD), and other brain disorders. Amyloid beta protein (Aβ) is the main component of amyloid plaques in the brains of people with AD. Several studies suggest that Aβ increases the generation of free radicals in neurons, which leads to oxidative damage and cell death. Aβ can also induce neuroinflammation by increasing pro-inflammatory cytokines and enzymes. Walnuts contain several components that have antioxidant and anti-inflammatory effects. Animal and human studies from our and other groups suggest that supplementation with walnuts in the diet may improve cognition and reduce the risk and/or progression of MCI and AD. In the transgenic AD mouse model (AD-tg), we have reported the beneficial effects of a diet with walnuts on memory, learning, motor coordination, anxiety, and locomotor activity. Human clinical trials have also suggested an association of walnut consumption with better cognitive performance and improvement in memory when compared to baseline in adults. Our recent study in AD-tg mice has shown that a walnut-enriched diet significantly improves antioxidant defense and decreases free radicals’ levels, lipid peroxidation, and protein oxidation when compared to a control diet without walnuts. These findings suggest that a diet with walnuts can reduce oxidative stress by decreasing the generation of free radicals and by boosting antioxidant defense, thus resulting in decreased oxidative damage to lipids and proteins. An in vitro study with synthetic Aβ showed that walnut extract can inhibit Aβ fibrillization and solubilize the preformed Aβ fibrils, suggesting an anti-amyloidogenic property of walnuts. Because it takes many years for cognitive impairment and dementia to develop, we suggest that early and long-term dietary supplementation with walnuts may help to maintain cognitive functions and may reduce the risk of developing, or delay the onset and/or slow the progression of, MCI and dementia by decreasing Aβ fibrillization, reducing oxidative damage, increasing antioxidant defense, and decreasing neuroinflammation. Furthermore, several animal and human studies have suggested that walnuts may also decrease the risk or progression of other brain disorders such as Parkinson’s disease, stroke, and depression, as well as of cardiovascular disease and type 2 diabetes. Together, these reports suggest the benefits of a walnut-enriched diet in brain disorders and in other chronic diseases, due to the additive or synergistic effects of walnut components for protection against oxidative stress and inflammation in these diseases.

Bioactives and health benefits of nuts and dried fruits

Nuts and dried fruits have been part of the human diet since prehistoric times. They are nutrient-rich foods and constitute an excellent means to deliver health-promoting bioactive compounds. As such, they serve as important healthful snack items, besides being part of many traditional and new recipes of gastronomy worldwide. Frequent consumption of nuts and/or dried fruits is highly recommended to obtain the full benefit of the nutrients, bioactives, and antioxidants that they contain, together with their desirable flavour. The macronutrients, micronutrients, and other health-promoting bioactive compounds contained in nuts and dried fruits may synergistically contribute to modulate the risk of cardiometabolic and other non-communicable diseases through various mechanisms. Experimental research, prospective studies, and human clinical trials have reported beneficial effects of nut consumption on various health outcomes. The benefits of dried fruits, however, have been less explored. This review summarizes recent findings on bioactive constituents, health claims, and health benefits of nuts and dried fruits and also discusses their great potential as healthy foods to benefit a number of diseases afflicting human beings.

Dietary Patterns and Cardiovascular Disease: Insights and Challenges for Considering Food Groups and Nutrient Sources

PURPOSE OF REVIEW

The relationship between dietary patterns and cardiovascular disease has been the subject of much research, but an important methodological consideration is the interdependence between the nutrient composition of foods and the recognition of healthy dietary patterns. This review considers some of the challenges in researching dietary patterns with implications for translation to public health promotions.

RECENT FINDINGS

A number of statistical methods have emerged for analysing dietary patterns using population dietary data. There are limitations in the assumptions underpinning food categorisation, but this research is able to consistently identify foods and dietary patterns that are positively related to health. Aligned to this activity is the ongoing development of food composition databases which has its own limitations such as keeping up to date with changing foods and newly identified components, sampling of foods, and developments in chemical analytical methods. Finally, dietary patterns form the basis for current dietary guidelines and related public health-oriented programs, but the issues raised for research (e.g. food categorisation and cuisine influences on dietary patterns) can also translate to these settings. The study of dietary patterns in cardiovascular disease prevention presents with a number of methodological challenges relating to the way food groups are formed and the limitations of food composition databases. Added to this are new considerations for the environmental impact of recommended dietary patterns. Future research across the entire knowledge chain should target more accurate methods in a number of analytical areas.

Associations of dietary patterns with hypertension among adults in Jilin Province, China: a structural equation modelling approach

OBJECTIVE

To explore the direct and indirect associations of dietary patterns with hypertension using structural equation modelling (SEM).

DESIGN

Factor analysis with varimax rotation was used to classify different dietary patterns and SEM was employed to investigate the associations of dietary patterns with hypertension. Total cholesterol to HDL-cholesterol (TC:HDL-C) ratio and LDL-cholesterol to HDL-cholesterol (LDL-C:HDL-C) ratio were used as observed indicator variables of the lipid latent variable. Waist circumference, body fat percentage and BMI, which were associated with hypertension, were used as observed indicator variables of the obesity latent variable.

SETTING

International Chronic Disease Cohort (ICDC) that began in 2005 with the purpose of describing the frequency and determinants of chronic diseases in Jilin Province, China.ParticipantsA total of 1492 adults (40-79 years) were enrolled in the baseline study from August 2010 to August 2011.

RESULTS

Hypertension prevalence in our study population was 34·9 %. It was found that the wine pattern, condiment pattern, obesity latent variable, lipid latent variable, glucose, age and family history of hypertension were factors that had an association with hypertension via SEM, and the corresponding coefficients were 0·056, 0·011, 0·230, 0·281, 0·098, 0·232 and 0·116, respectively.

CONCLUSIONS

The wine pattern and lipid latent variable had positive direct associations with hypertension. The condiment pattern had a positive indirect association with hypertension via the obesity latent variable. The vegetables pattern, modern pattern and snack pattern were not associated with hypertension.

The Relationship between Dietary Patterns with Blood Pressure in Iranian Army Staffs

Background:

Hypertension is one of the most common noncommunicable diseases in the world. One of the most effective factors on blood pressure (BP) is nutrition. The aim of this study was to examine the relationship between dietary patterns and BP among military staffs.

Materials and Methods:

The study was carried out among 405 military staffs between 22 and 51 years old. Demographic, anthropometric information, and BP of participants were evaluated by standard methods. The dietary intakes were collected using a food frequency questionnaire (FFQ). Dietary patterns were identified using a posteriori method, factor analysis, and based on the FFQ. To check the relationship between BP and dietary patterns, we used multivariate linear regression in different models, relationship were adjusted for Age, sex, marital, smoking, income, body mass index, waist-to-hip ratio, family history of hypertension, energy intake, and physical activity level.

Results:

Two dominant dietary patterns were identified in the participants: Healthy and western pattern. The association of dietary patterns with systolic BP (SBP) and diastolic BP (DBP) was exhibited in different models. There was no relationship between SBP and DBP with healthy pattern (P = 0.269 and P = 0.638, respectively) and western pattern (P = 0.648 and P = 0.315, respectively) after adjustments.

Conclusion:

Our findings indicated that dietary patterns did not have any significant relationship with SBP and DBP after adjustment for confounders in the healthy military. To identify the dietary patterns associated with BP in healthy military, more strong design studies and more participants should be conducted in the future.

Effect of individualised dietary advice for weight loss supplemented with walnuts on blood pressure: the HealthTrack study

BACKGROUND/OBJECTIVES

In addition to weight-loss, healthy dietary patterns and lower sodium intakes can help reduce blood pressure (BP), but individualised dietary advice may be necessary to achieve these effects. This study aimed to examine the impact of individualised dietary advice on BP in the intensive phase of a weight-loss trial.

SUBJECTS/METHODS

Secondary analysis of baseline and 3-month data from the HealthTrack randomised controlled trial (n = 211). Participants were randomly assigned to one of three dietary advice groups: general advice (control), individualised advice (intervention group, I), or intervention group supplemented with 30 g walnuts/day (IW). Resting BP and 24-h urine sodium and potassium were measured. Dietary intake was evaluated through diet history interviews.

RESULTS

Unadjusted SBP reduced significantly in all groups (IW and I groups P < 0.001; control group P = 0.002) and DBP in IW and I groups (P < 0.001). Compared to controls, the reductions in BP were 3-4 mmHg greater in the I and IW groups, but this only reached significance for DBP in the I group (-3.3 mmHg; P = 0.041). After controlling for age, sex, medication, weight-loss, physical activity and smoking, only the IW group showed a significant association between SBP reduction and increased urinary potassium (β = -0.101, P = 0.044), decreased sodium:potassium ratio (β = 2.446, P = 0.037) and increased consumption of seed and nut products and dishes (β = -0.108, P = 0.034).

CONCLUSIONS

Dietary patterns with distinctive foods and lower sodium:potassium ratios may enhance the effects of weight-loss on BP. The patterns were best achieved with individualised dietary advice and food supplements.

Dietary behaviour changes to improve nutritional quality and health outcomes

This narrative review examines the changes required in dietary behaviours to address the current global burden of disease resulting from diet-associated cardiometabolic dysfunction. Beginning with known relationships between nutritional factors and health outcomes, the review identifies a number of problems with current dietary behaviours, using examples from the Australian context. Implications for practice are then discussed drawing on insights from research in dietary trials. From a concerted research effort across the globe, the effects of foods, food components and dietary patterns on cardiometabolic parameters have been reasonably well exposed. The evidence base for these effects underpins dietary guidelines, which aim to meet nutritional requirements and protect against cardiometabolic disease. Thus foods recommended in dietary guidelines tend to be consistent with research that identifies foods that appear protective and those that appear detrimental to health. The need for dietary behaviour change is apparent through analyses that have exposed increasing consumption of detrimental foods, despite the availability of healthy foods. However, behaviour change is a complex area, and where weight loss is also required, there is high level evidence that interdisciplinary efforts combining diet, physical activity and psychological support are warranted. Insights from dietary trials and research indicate that focussing on foods and dietary patterns is integral to the specific dietary change required for health outcomes, but social and behavioural factors will influence the achievement of these changes.