Dietary Acid Load and Potassium Intake Associate with Blood Pressure and Hypertension Prevalence in a Representative Sample of the German Adult Population

The dietary acid load is associated with disease severity in psoriatic arthritis

OBJECTIVES

An acidogenic diet, by disrupting the blood pH equilibrium, can contribute to metabolic acidosis and lead to inflammation. Therefore, we hypothesized that dietary acid load (DAL) increases disease activity and inflammation in psoriatic arthritis (PsA) patients.

METHODS

This study was conducted with 58 obese/overweight patients, aged 20-65 years. Dietary intake was assessed using a 3-consecutive-day 24-hour recall. The DAL was evaluated through the PRAL (potential renal acid load) and NEAP (net endogenous acid production) and divided into the low and high groups by their median values. The disease activity assessments, anthropometric measurements, dietary data, and blood parameters of patients were recorded and compared at the low and high DAL groups.

RESULTS

We observed that patients in the high NEAP and PRAL groups had worse PsA pattern scores (P < 0.05). Also, PRAL and NEAP scores were positively associated with Disease Activity Index for Psoriatic Arthritis, Health Assessment Questionnaire, and Psoriatic Arthritis Impact of Disease-12 (PSAID-12) scores. After adjusting age, sex, smoking, and body mass index, 1 mEq increase in PRAL and NEAP was associated with an elevation of Disease Activity Index for Psoriatic Arthritis (0.506 and 0.486 points, respectively).

CONCLUSIONS

These results showed a close relationship between DAL and PsA symptoms. An acidogenic diet may negatively affect PsA prognosis. Healthy eating recommendations should be part of the management of the disease.

Effects of higher dietary acid load: a narrative review with special emphasis in children

Metabolic effects of high diet acid load (DAL) have been studied for years in adults, although only recently in children. Contemporary diets, especially those of Western societies, owe their acidogenic effect to high animal-origin protein content and low contribution of base-forming elements, such as fruits and vegetables. This imbalance, where dietary acid precursors exceed the body's buffering capacity, results in an acid-retaining state known by terms such as "eubicarbonatemic metabolic acidosis," "low-grade metabolic acidosis," "subclinical acidosis," or "acid stress". Its consequences have been linked to chronic systemic inflammation, contributing to various noncommunicable diseases traditionally considered more common in adulthood, but now have been recognized to originate at much earlier ages. In children, effects of high DAL are not limited to growth impairment caused by alterations of bone and muscle metabolism, but also represent a risk factor for conditions such as obesity, insulin resistance, diabetes, hypertension, urolithiasis, and chronic kidney disease (CKD). The possibility that high DAL may be a cause of chronic acid-retaining states in children with growth impairment should alert pediatricians and pediatric nephrologists, since its causes have been attributed traditionally to inborn errors of metabolism and renal pathologies such as CKD and renal tubular acidosis. The interplay between DAL, overall diet quality, and its cascading effects on children's health necessitates comprehensive nutritional assessments and interventions. This narrative review explores the clinical relevance of diet-induced acid retention in children and highlights the potential for prevention through dietary modifications, particularly by increasing fruit and vegetable intake alongside appropriate protein consumption.

Dietary acid load in health and disease

Maintaining an appropriate acid-base equilibrium is crucial for human health. A primary influencer of this equilibrium is diet, as foods are metabolized into non-volatile acids or bases. Dietary acid load (DAL) is a measure of the acid load derived from diet, taking into account both the potential renal acid load (PRAL) from food components like protein, potassium, phosphorus, calcium, and magnesium, and the organic acids from foods, which are metabolized to bicarbonate and thus have an alkalinizing effect. Current Western diets are characterized by a high DAL, due to large amounts of animal protein and processed foods. A chronic low-grade metabolic acidosis can occur following a Western diet and is associated with increased morbidity and mortality. Nutritional advice focusing on DAL, rather than macronutrients, is gaining rapid attention as it provides a more holistic approach to managing health. However, current evidence for the role of DAL is mainly associative, and underlying mechanisms are poorly understood. This review focusses on the role of DAL in multiple conditions such as obesity, cardiovascular health, impaired kidney function, and cancer.

A high dietary acid load can potentially exacerbate cardiometabolic risk factors: An updated systematic review and meta-analysis of observational studies

AIMS

Chronic metabolic acidosis has been shown to be associated with cardiometabolic risk factors. The aim of the currently updated meta-analysis was to explore the association between Potential Renal Acid Load (PRAL) and Net Endogenous Acid Production (NEAP) with these risk factors.

DATA SYNTHESIS

Databases were searched up to May 2023. The mean of waist circumference (WC), body mass index (BMI), high- and low-density lipoprotein-cholesterol (HDL-C and LDL-C), triglyceride (TG), total cholesterol (TC), fasting blood sugar (FBS), and systolic- and diastolic blood pressure (SBP and DBP) in highest category vs lowest categories of NEAP and PRAL were recorded. Effect sizes were generated as weighted mean difference (WMD). Results showed that SBP, DBP, and WC had a significant difference in the upper and lower categories of PRAL (WMDSBP: 1.466 mmHg; 95% CI: 2.121, -0.811; P<0.001, WMDDBP: 0.710 mmHg; 95 % CI: 1.170, -0.249; P=0.003, and WMDWC: 0.819 cm; 95% CI: 1.446, -0.192; P=0.010) or NEAP (WMDSBP: 1.690 mmHg; 95% CI: 2.789, -0.591; P=0.003, WMDDBP: 1.076 mmHg, and WMDWC: 1.325 cm; 95% CI: 1.901, -0.749; P<0.001; 95% CI: 1.938, -0.214; P =0.014). The lowest versus highest categories of dietary PRAL were associated with lower BMI (WMDPRAL: 0.297 kg/m2; 95 % CI: 0.440, -0.154; P<0.001) and TG (WMD: 2.280 mg/dl; 95%CI: 3.828, -0.732; P=0.004; I2=99.4 %; P<0.001).

CONCLUSIONS

High DAL can be considered as an independent risk factor for increasing anthropometric indices, blood pressure, and TG. This study registered in the PROSPERO database (Registration No. CRD42023402985).

Assessment of Dietary Acid Load in Children with Chronic Kidney Disease: An Observational Study

Introduction

Dietary acid load (DAL), which reflects the balance between acid- and alkaline-forming foods, is a modifiable risk factor for metabolic acidosis in CKD. Owing to the paucity of data in the Indian context, we undertook this cross-sectional study to estimate DAL and assess acid and alkaline food consumption in children with CKD2-5D (Chronic kidney disease stage 2 to 5 and 5D-those on hemodialysis).

Methods

Clinical profile, dietary assessment of energy, protein intake/deficits, and macronutrients were noted and computed using software created by the division of nutrition, St John's research institute based on Kidney Disease Outcomes Quality Initiative (KDOQI) guidelines in clinically stable children with CKD2-5D. DAL was estimated using potential renal acid load (PRAL in mEq/day) = (0.49 × protein intake in g/day) + (0.037 × phosphorus-intake in mg/day) - (0.02 × potassium intake in mg/day) - (0.013 × calcium intake in mg/day) - (0.027 × magnesium intake in mg/day). A positive dietary PRAL (>0) favors acidic content and negative (<0) favors alkaline content. PRAL was stratified into quartiles for analysis. The association of various clinical and dietary parameters were analysed across these quartiles.

Results

Eighty-one children [of mean age 122 ± 47 months; 56 (69%) boys, 29 (36%) on dialysis, 62 (77%) non-vegetarians] were studied. Twenty-eight (34%) were on bicarbonate supplements. A positive PRAL (9.97 ± 7.7 mEq/day) was observed in 74/81 (91%) children with comparable proportions in those with CKD2-5 and 5D [47/52 (90%) vs. 27/29 (93%) respectively, P > 0.05]. Protein intake was significantly higher in the highest quartile compared to the lowest quartile of PRAL in CKD2-5 (55 ± 16 g/day vs. 40 ± 14 g/day, P < 0.001) and 5D groups (47 ± 15 g/day vs. 25 ± 11 g/day, P = 0.002). A majority of the participants 60/81 (74%) consumed highly acidic and minimal alkali foods.

Conclusion

In children with CKD2-5D, PRAL estimation revealed high DAL in the majority with a high consumption of acidic foods. These findings provide implications for appropriate dietary counseling in children with CKD.

Association between Dietary Acid Load and Hypertension in Chinese Adults: Analysis of the China Health and Nutrition Survey (2009)

(1) Background: Current studies show conflicting results regarding the relationship between dietary acid load (DAL) and blood pressure. (2) Methods: The study used data from the Chinese Health and Nutrition Survey (CHNS) 2009. DAL was assessed on the basis of potential renal acid load (PRAL) and net endogenous acid production (NEAP). To examine the link between DAL and the risk of hypertension, a multivariate logistic regression model was utilized. (3) Results: A total of 7912 subjects were enrolled in the study, of whom 2133 participants had hypertension, a prevalence of 27.0%. After accounting for potential covariates, higher PRAL and NEAP scores were associated with a greater likelihood of developing hypertension, with ORs of 1.34 (95% CI, 1.10-1.62) and 1.29 (95% CI, 1.09-1.53) for PRAL and NEAP scores in Q4, respectively, compared with Q1. In the male group, PRAL and NEAP scores were positively linked to hypertension risk, with ORs of 1.33 (95% CI, 1.06-1.67) and 1.46 (95% CI, 1.14-1.85) for PRAL and NEAP scores in Q4, respectively, compared with Q1, while no significant associations were observed in the female group. Correlations between PRAL scores and hypertension risk lacked significance in the subgroup analyses for participants aged <60 years. There was a significant nonlinear connection observed in the dose-response relationship between DAL (based on PRAL) and hypertension; (4) Conclusions: In Chinese adults, higher PRAL and NEAP scores were positively linked to hypertension risk. This implies that a diet with a low DAL may be a favorable dietary pattern for lowering blood pressure.

The Impact of Plant-Based Diets on Dietary Acid Load Metrics in Venezuela: A Cross-Sectional Study

Dietary acid load (DAL) is an important determinant of the acid-base balance in humans and has been associated with several chronic non-communicable diseases. Plant-based diets, including vegetarian and vegan diets, decrease DAL-although their alkalizing potential varies substantially. Their net effect on common DAL scores, including potential renal acid load and net endogenous acid production, has been insufficiently quantified and is poorly understood-particularly in populations outside of Europe and North America. We assessed the associations between three plant-based dietary patterns (flexitarian vs. lacto-ovo-vegetarian vs. vegan diet) and DAL scores in a healthy Venezuelan population in the metropolitan area of Puerto La Cruz, Venezuela. Substantial differences in DAL scores were observed, whereby the vegan diet yielded the highest alkalizing potential, followed by the lacto-ovo-vegetarian and the flexitarian diet. DAL scores were substantially lower in comparison to European and North American plant-based populations, probably due to the higher potassium intake (exceeding 4000 mg/d in vegans), the higher magnesium intake (390.31 ± 1.79 mg/d in vegans) and the lower intake of protein in vegans and lacto-ovo-vegetarians. Additional studies in other non-industrialized populations are warranted to allow for a better understanding of the (numeric) impact of plant-based dietary patterns on DAL scores, potentially allowing for an establishment of reference ranges in the near future.

Observational and clinical evidence that plant-based nutrition reduces dietary acid load

Contemporary diets in Western countries are largely acid-inducing and deficient in potassium alkali salts, resulting in low-grade metabolic acidosis. The chronic consumption of acidogenic diets abundant in animal-based foods (meats, dairy, cheese and eggs) poses a substantial challenge to the human body's buffering capacities and chronic retention of acid wherein the progressive loss of bicarbonate stores can cause cellular and tissue damage. An elevated dietary acid load (DAL) has been associated with systemic inflammation and other adverse metabolic conditions. In this narrative review, we examine DAL quantification methods and index observational and clinical evidence on the role of plant-based diets, chiefly vegetarian and vegan, in reducing DAL. Quantitation of protein and amino acid composition and of intake of alkalising organic potassium salts and magnesium show that plant-based diets are most effective at reducing DAL. Results from clinical studies and recommendations in the form of expert committee opinions suggest that for a number of common illnesses, wherein metabolic acidosis is a contributing factor, the regular inclusion of plant-based foods offers measurable benefits for disease prevention and management. Based on available evidence, dietary shifts toward plant-based nutrition effectively reduces dietary-induced, low-grade metabolic acidosis.

Dietary acid load and mortality from all causes, CVD and cancer: results from the Golestan Cohort Study

Given the limited studies and controversial results on association between dietary acid load and mortality from CVD and cancers, we aimed to investigate this association in a large population cohort study in Middle East, with a wide range of dietary acid load. The study was conducted on the platform of the Golestan Cohort Study (GCS), which enrolled 50 045 participants in 2004-2008. Dietary intake was assessed using a validated FFQ. Dietary potential renal acid load (PRAL) score was calculated from nutrient intake. Death and its causes were identified and confirmed by two or three physicians. Cox proportional hazards regression was used to estimate hazard ratio (HR) and 95 % CI for total and cause-specific mortalities. Then, the associations were modelled using restricted cubic splines. PRAL range was -57·36 to +53·81 mEq/d for men and -76·70 to +49·08 for women. During 555 142 person-years of follow-up, we documented 6830 deaths, including 3070 cardiovascular deaths, 1502 cancer deaths and 2258 deaths from other causes. For overall deaths, in final model after adjustment for confounders, participants in the first and fifth quintiles of PRAL had a higher risk of mortality compared with the second quintile of PRAL (HR: 1·08; 95 % CI1·01, 1·16 and HR: 1·07; 95 % CI 1·01, 1·15, respectively); Pfor trend < 0·05). Participants in the first and fifth quintiles of PRAL had a 12 % higher risk of CVD mortality compared with the Q2 of PRAL (HR: 1·12; 95 % CI 1·01-1·25 and HR: 1·12; 95 % CI 1·01, 1·26, respectively; Pfor trend < 0·05). We found that all-cause and CVD mortality rates were higher in the lowest and highest PRAL values, in an approximately U-shaped relation (P-values for the overall association and the non-linear association of energy-adjusted PRAL with total mortality were < 0·001 and < 0·001, and with CVD mortality were 0·008 and 0·003, respectively). Our results highlight unfavourable associations of high acidity and alkalinity of diet with the increased total and CVD mortality risk. It may be important to consider a balanced acid-base diet as a protective strategy to prevent pre-mature death, especially from CVD.

Dietary acid load modifies the effects of ApoA2-265 T > C polymorphism on lipid profile and serum leptin and ghrelin levels among type 2 diabetic patients

This investigation with aimed the effect of APOA2-265 T > C polymorphism and dietary acid load (DAL) as either potential renal acid load (PRAL) and net endogenous acid production (NEAP) intake interaction on metabolic markers in type 2 diabetes mellitus (T2DM). In present cross-sectional study, 737 patients with T2DM (290 men and 447 women) were enlisted from diabetes centers in Tehran. The dietary intakes of all participants during the last year was acquired by a validated semi-quantitative food frequency (FFQ) questionnaire. Polymerase chain reaction (PCR) was used for genotyping the APOA2-265 T > C. Biochemical indises containing leptin, ghrelin, total cholesterol (Bailey et al., J Clin Invest 97:1147-1453, 1996), low-density lipoprotein cholestrol (LDL-C), high-density lipoprotein cholestrol (HDL-C), triglyceride (TG), superoxide dismutase (SOD), high sensitivy C-reactive protein (hs-CRP), total antioxidant capacity (TAC), pentraxin-3 (PTX3), prostaglandin F2α (PGF2α) and interleukin 18 (IL18) were measured by standard method. Atherogenic indices (AIP, AC, CR-I, CR-II) were calculated. The gene-diet interactions were evaluated using an GLM. The frequency overall prevalence of rs5082 genotypes was 63.82 and 36.17% for T-allele and C-allele respectively. TG, Ghrelin, and hs-CRP concentrations were significantly higher among carriers with C allele than TT homozygotes. However, TC/CC genotypes have lower PTX3 than TT homozygotes (P < 0.05). C-allele carriers had highest mean of BMI (P_NEAP=0.04, P_PRAL = 0.006), WC (P_NEAP=0.04, P_PRAL = 0.04), TC (P_NEAP=0.03, P_PRAL = 0.01), ghrelin (P_NEAP=0.01, P_PRAL = 0.04), and leptin (P_NEAP=0.04, P_PRAL = 0.03) when placed in top tertiles of NEAP and PRAL.BMI, WC, TC, ghrelin, and leptin levels may be modified in C carriers by decreasing DAL, though, further investigations are required to confirm these findings.

Dietary Contributions to Metabolic Acidosis

Eating a net acid-producing diet can produce an "acid stress" of severity proportional to the diet net acid load, as indexed by the steady-state renal net acid excretion rate. Depending on how much acid or base is ingested or produced from endogenous metabolic processes and how well our homeostatic mechanisms can buffer or eliminate the additional acids or bases, we can alter our systemic acid-base balance. With increasing age, the kidney's ability to excrete daily net acid loads declines (a condition similar to that of mild CKD), invoking increased utilization of potential base stores (eg, bone, skeletal muscle) on a daily basis to mitigate the acid accumulation, thereby contributing to development of osteoporosis, loss of muscle mass, and age-related renal insufficiency. Patients suffering from more advanced CKD often present with more severe acid stress or metabolic acidosis, as the kidney can no longer excrete the entire acid load. Alkaline diets based on fruits and vegetables may have a positive effect on long-term preservation of renal function while maintaining nutritional status. This chapter discusses the biochemistry of dietary precursors that affect acid or base production.

Dietary acid load and cardiovascular diseases

Diet affects the body's acid-base balance by providing acid or alkali precursors in the metabolism. The importance of the acid-base balance of the diet for cardiovascular diseases, which have become the most important cause of morbidity on the global scale, has started to take its place in the literature. The prediction of endogenous acid production in dietary acid-base balance is expressed as dietary acid load. Although the available information about the effect of dietary acid load on cardiovascular diseases is limited, possible mechanisms are indicated as excessive calcium and magnesium excretion from the kidneys, reduced urinary citrate excretion, and excessive cortisol production. Metabolic acidosis has an important role in the development of cardiometabolic abnormalities, especially insulin resistance. Studies examining the relationship between dietary acid load and cardiovascular disease are limited and there is an inconsistency between studies. Practices for determining risk factors for cardiovascular diseases and preventing their effects are very important for the protection and improvement of health. Considering dietary acid load when planning a diet for individuals with cardiovascular diseases can help increase the effectiveness of the diet. The purpose of this review is to examine the effect of dietary acid load on cardiovascular diseases.

Dietary Acid Load is Associated with Hypertension and Diabetes in the Elderly

BACKGROUND

Diet can affect the body's acid-base balance due to its content of acid or base precursors. There is conflicting evidence for the role of metabolic acidosis in the development of cardiometabolic disorders, hypertension (HT), and insulin resistance (IR).

OBJECTIVE

We hypothesize that dietary acid load (DAL) is associated with adverse metabolic risk factors and we aimed to investigate this in the elderly.

METHODS

A total of 114 elderly participants were included in the study. The participants were divided into four groups such as HT, diabetes (DM), both HT and DM, and healthy controls. Anthropometric, biochemical, and clinical findings were recorded. Potential renal acid load (PRAL) and net endogenous acid production (NEAP) results were obtained from three-day, 24-hour dietary records via a nutrient database program. (BeBiS software program).

RESULTS

The groups were matched for age, gender, and BMI. There was a statistically significant difference between the groups in terms of NEAP (p=0.01) and no significant difference for PRAL (p=0.086). The lowest NEAP and PRAL levels were seen in the control group while the highest in the HT group. Both NEAP and PRAL were correlated with waist circumference (r=0,325, p=0.001; r=0,231, p=0,016, respectively).

CONCLUSION

Our data confirmed that subjects with HT and DM had diets with greater acid-forming potential. High NEAP may be a risk factor for chronic metabolic diseases, particularly HT. PRAL couldn't be shown as a significantly different marker in all participants. Dietary content has a significant contribution to the reduction of cardiovascular risk factors such as HT, DM, and obesity.

Dietary acid load and risk of cardiovascular disease: a prospective population-based study

BACKGROUND AND AIM

Considering the inconsistencies in the cardiovascular effects of dietary acid load and the impact of dietary acidity on the acid-base homeostasis within the body, we aimed to assess the association of dietary acid load and the risk of cardiovascular disease (CVD) in a prospective community-based study.

MATERIALS AND METHODS

Participants (n = 2369) free of CVD at baseline (2006-2008) were included from the Tehran Lipid and Glucose Study (TLGS) and followed up for a mean of 6.7 ± 1.4 years. Dietary intakes of the participants were assessed using a semi-quantitative food frequency questionnaire (FFQ). The dietary acid load was evaluated by Potential Renal Acid Load (PRAL) and Net Endogenous Acid Production (NEAP) scores. Both scores have used the macronutrient and micronutrient data of the Food Frequency Questionnaires. Multivariate Cox proportional hazard regression models were used to estimate the 6-years incident risk of CVDs across tertiles of PRAL and NEAP scores.

RESULTS

Mean age and body mass index of participants were 38.5 ± 13.3 years and 26.6 ± 4.8 kg/m² at baseline. Within 6.7 ± 1.4 years of follow-up, 79 cases of cardiovascular events were reported. NEAP was significantly associated with the incidence of CVDs (HRs = 0.50, CI 0.32-0.96; P for trend = 0.032); however, after adjusting for potential confounders, no significant associations were observed between PRAL and NEAP scores and the risk of CVDs.

CONCLUSIONS

This study failed to obtain independent associations between dietary acid load and the incidence of CVDs among an Asian population.

Dietary acid load in children with chronic kidney disease

BACKGROUND/OBJECTIVES

Western diet is characterized by a high acid load that could generate various degrees of metabolic acidosis, of which at least the stronger forms are known to contribute to the progression of chronic kidney disease (CKD). The aim of this study was to estimate the potential renal acid load (PRAL) and acid base status in CKD patients attended at the Children's Hospital J.M. de los Ríos in Caracas, Venezuela from April 2015 to February 2016.

SUBJECTS/METHODS

Twenty-seven children with CKD were included. Diet composition was evaluated by a food frequency questionnaire and a 24-h intake reminder. PRAL was calculated by the Remer and Manz method. Laboratory tests included serum creatinine, electrolytes and venous gases.

RESULTS

Protein intake was above recommendations in 21 patients (78.6%). Average vegetable and fruit intake was 0.4 and 1.5 servings per day, respectively. Mean PRAL was 16 ± 10.7 mEq/day. PRAL correlated positively with energy (p = 0.005), protein (p = 0.001) and fat intake (p = 0.0001), daily servings of dairy (p = 0.04) meat (p = 0.001) and cereals (0.001) and negatively with vegetable intake (p = 0.04). Serum pH and bicarbonate were 7.3 ± 0.08 and 20.46 ± 4.5 mEq/L, respectively. Twenty-one patients (80.7%) with metabolic acidosis were treated with sodium bicarbonate.

CONCLUSIONS

Dietary pattern of Venezuelan children with CKD may constitute a risk factor for the progression of the disease by promoting metabolic acidosis via unfavorable dietary acid loads. PRAL should be assessed as a valuable guide for nutritional counseling in children with CKD.

Dietary Acid Load and Cardiometabolic Risk Factors-A Narrative Review

The Western, diet rich in acidogenic foods (e.g., meat, fish and cheese) and low in alkaline foods (e.g., vegetables, fruits and legumes), is deemed to be a cause of endogenous acid production and elevated dietary acid load (DAL), which is a potential cause of metabolic acidosis. Multiple authors have suggested that such a dietary pattern increases the excretion of calcium and magnesium, as well as cortisol secretion. In addition, it is associated with decreased citrate excretion. All of these seem to increase blood pressure and insulin resistance and may contribute to the development of cardiometabolic disorders. However, there are inconsistencies in the results of the studies conducted. Therefore, this narrative literature review aims to present the outcomes of studies performed in recent years that investigated the association between DAL and the following cardiometabolic risk factors: blood pressure, hypertension, carbohydrate metabolism and lipid profile. Study outcomes are divided into (i) statistically significant positive association, (ii) statistically significant inverse association, and (iii) no statistically significant association.

Estimates of renal net acid excretion and their relationships with serum uric acid and hyperuricemia in a representative German population sample

BACKGROUND/OBJECTIVE

Preliminary interventional data suggest that a reduction of dietary acid load raises renal uric acid excretion and decreases serum uric acid (SUA). In line with this, in a recent cross-sectional analysis of a representative adult population sample, a higher potential renal acid load (PRAL) was found to associate with higher SUA levels. Against this background, we re-examined the relationship of the body's acid load with SUA and hyperuricemia using nutrition-derived estimates of renal net acid excretion (NAE).

SUBJECTS/METHODS

Cross-sectional analyses were performed in n = 6894 participants (18-79 y) of the German Health Interview and Examination Survey for Adults (DEGS1). Two different approaches were used to estimate NAE, one based on the sum of food frequency questionnaire (FFQ)-derived PRAL and body-surface area-derived organic acids (eNAE_PRAL+OA) and the other based on FFQ-derived protein and potassium intake ratios (eNAE_Prot/K). The associations of eNAE_PRAL+OA and eNAE_Prot/K with SUA were analyzed in multiple linear regression models. Multiple logistic regressions were used to calculate odds ratios (OR) for hyperuricemia comparing higher (T3) and lower (T1) tertiles of the NAE estimates.

RESULTS

After adjusting for relevant confounders, eNAE_PRAL+OA (p = 0.0048) and eNAE_Prot/K (p = 0.0023) were positively associated with SUA. In addition, participants with a higher eNAE_PRAL+OA or eNAE_Prot/K had higher ORs for having hyperuricemia (OR: 1.73, 95% CI: 1.24-2.40, OR: 1.51, 95% CI: 1.10-2.08, respectively).

CONCLUSION

The results substantiate findings of a previous analysis that dietary acid load is a potential influencing factor on SUA. This implicates that a lower dietary acid load may have beneficial effects on SUA.

Dietary acid load, blood pressure, fasting blood sugar and biomarkers of insulin resistance among adults: Findings from an updated systematic review and meta-analysis

OBJECTIVES

There is no clear summarised report of the association between dietary acid load components including potential renal acid load (PRAL) and net-endogenous acid production (NEAP) with cardiometabolic risk factors. In the current meta-analysis, we aimed to systematically review and summarise the eligible observational studies evaluating the association between PRAL and NEAP with blood pressure and hypertension and markers of glucose haemostasis among adults.

DESIGN AND SETTING

In a systematic search from PubMed, SCOPUS, Web of Sciences and Cochrane electronic databases up to May 2019, relevant studies were included in the literature review. Observational studies evaluating the association between PRAL and NEAP with the systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood glucose, insulin, homeostatic model assessment of insulin resistance (HOMA-IR), haemoglobin A₁ C (HbA₁ C), HOMA-β and quantitative insulin check index (QUICKI) and also prevalence or odds of hypertension, hyperglycaemia and diabetes were included.

RESULTS

Total number of studies included in the 14 separate meta-analyses were as follows: Mean (SD) of SBP (PRAL, n = 12; NEAP, n = 6), mean (SD) of DBP (PRAL, n = 8; NEAP, n = 3), mean (SD) of FBS (PRAL, n = 12; NEAP, n = 5), mean (SD) of HbA₁ C (PRAL, n = 6; NEAP, n = 4), mean (SD) of HOMA-IR (PRAL, n = 7), mean (SD) of insulin (PRAL, n = 7; NEAP, n = 2); OR of type 2 diabetes mellitus (T₂ DM) (PRAL, n = 8; NEAP; n = 6), HTN prevalence (PRAL, n = 9; NEAP, n = 9), T₂ DM prevalence (PRAL, n = 7; NEAP, n = 6). According to our results, being in the highest PRAL categories was associated with higher SBP (WMD = 0.98; CI: 0.51, 1.45; P < .001), DBP (WMD = 0.61; CI: 0.089, 1.135; P = .022), insulin (WMD = -0.235, CI: 0.070, 0.400; P = .005), higher odds of diabetes (OR = 1.19; CI: 1.092, 1.311; P < .001), higher prevalence of T₂ DM (13% and 11% in highest vs lowest category). While, being in the highest category of NEAP was only associated with higher odds of diabetes (OR = 1.22; CI: 1.14, 1.31, P < .001). In subgroup analysis for finding the possible source of heterogeneity, the continent, dietary assessment tool, sample size and gender were the potent sources of heterogeneity. No association between PRAL and NEAP with HbA₁ C, HOMA-IR was reported.

CONCLUSIONS

In the current meta-analysis, we found potent negative effects of high dietary acid load particularly higher PRAL scores cardiometabolic risk factors. Therefore, lower acidogenic food ingredients in the diets are suggested for the prevention of cardiovascular risk factors and diabetes.

Association between dietary acid load and the risk of hypertension among adults from South China: result from nutrition and health survey (2015-2017)

Background

Higher dietary acid load (DAL) was considered to be associated with an elevated risk of hypertension, while related data from mainland China remains scarce and incomplete. We aim to evaluate the association between DAL and the risk of hypertension among adults from South China.

Methods

We conducted a nutrition and health survey in Guangdong Province located in southern China from 2015 to 2017. A four-stage probability sampling method was utilized to select representative samples of citizens aged ≥18 years old. DAL was assessed by potential renal acid load (PRAL) and net endogenous acid production (NEAP). Participants were divided to 4 groups (Q1-Q4) according to the quartile points of PRAL or NEAP distributions. Generalized linear mixed effects models were applied to evaluate the association between DAL and the risk of hypertension.

Results

A total of 3501 individuals were eligible for this study and 45.9% was male participants. Hypertension rate was 30.7%. A higher PRAL was associated with higher prevalence rate of hypertension among the male (P-trend = 0.03). OR for Q2 was 1.34 (95%CI, 0.94–1.91), Q3 was 1.53 (95%CI = 1.08, 2.16) and Q4 was 1.51 (95%CI, 1.08–2.16) among the male. However, as for total participants, the female, the participants with ≤55 years or participants with > 55 years, the associations were lack of significance. With respect to association between NEAP and hypertension, non-significant results were identified.

Conclusions

The current study indicated male hypertension was associated with higher PRAL, while given to this study was cross-sectional design, further studies are warranted to verify the association.

Prevalence and factors associated with hypertension among adults in rural Sylhet district of Bangladesh: a cross-sectional study

OBJECTIVES

Low-income and middle-income countries are undergoing epidemiological transition, however, progression is varied. Bangladesh is simultaneously experiencing continuing burden of communicable diseases and emerging burden of non-communicable diseases (NCDs). For effective use of limited resources, an increased understanding of the shifting burden and better characterisation of risk factors of NCDs, including hypertension is needed. This study provides data on prevalence and factors associated with hypertension among males and females 35 years and older in rural Bangladesh.

METHODS

This is a population-based cross-sectional study conducted in Zakiganj and Kanaighat subdistricts of Sylhet district of Bangladesh. Blood pressure was measured and data on risk factors were collected using STEPS instrument from 864 males and 946 females aged 35 years and older between August 2017 and January 2018. Individuals with systolic blood pressure of ≥140 mm Hg or diastolic blood pressure of ≥90 mm Hg or taking antihypertensive drugs were considered hypertensive. Bivariate and multivariate analyses were performed to identify factors associated with hypertension.

RESULTS

The prevalence of hypertension was 18.8% (95% CI 16.3 to 21.5) and 18.7% (95% CI 16.3 to 21.3) in adult males and females, respectively. Among those who were hypertensive, the prevalence of controlled, uncontrolled and unaware/newly identified hypertension was 23.5%, 25.9% and 50.6%, respectively among males and 38.4%, 22.6% and 39.0%, respectively among females. Another 22.7% males and 17.8% females had prehypertension. Increasing age and higher waist circumference (≥90 cm for males and ≥80 cm for females) were positively associated with hypertension both in males (OR 4.0, 95% CI 2.5 to 6.4) and females (OR 2.8, 95% CI 2.0 to 4.1).

CONCLUSIONS

In view of the high burden of hypertension and prehypertension, a context-specific scalable public health programme including behaviour change communications, particularly to increase physical activity and consumption of healthy diet, as well as identification and management of hypertension needs to be developed and implemented.

Dietary acid load and risk of hypertension: A systematic review and dose-response meta-analysis of observational studies

BACKGROUND AND AIM

Previous studies have assessed diet-induced mild metabolic acidosis in relation to blood pressure, however, data are conflicting. Current systematic review and dose-response meta-analysis aimed to summarize earlier findings from observational studies on the association between dietary acid load and hypertension.

METHODS AND RESULTS

We searched the online databases for relevant publications up to Feb 2019, using relevant keywords. Overall, 14 studies (3 prospective and 11 cross-sectional studies) that included 306,183 individuals and 62,264 cases of hypertension were included in the current meta-analysis. Combining effect sizes from both prospective and cross-sectional studies revealed no significant non-linear association between dietary acid load (based on net endogenous acid production (NEAP) method) and hypertension. However, stratified analysis based on study design showed a significant non-linear association between dietary acid load and hypertension in prospective studies (P = 0.006), but not cross-sectional ones. According to linear dose-response analysis, no significant association was found between dietary acid load (based on NEAP) and hypertension (combined effect size: 1.01, 95% CI: 0.97-1.06, P = 0.51). In terms of dietary acid load based on potential renal acid load (PRAL) method, no significant non-linear association was seen with hypertension (P = 0.52). However, in linear dose-response analysis, a-20 unit increase in PRAL values was associated with 3% increased risk of hypertension (combined effect size: 1.03, 95% CI: 1.00-1.06, P = 0.03).

CONCLUSION

We found a significant positive association between dietary acid load and hypertension. Further studies, particularly those with prospective nature, are needed to confirm our findings.

Elevated hypertension risk associated with higher dietary acid load: A systematic review and meta-analysis

BACKGROUND & AIMS

The association between dietary acid load and hypertension risk is inconclusive. We conducted a systematic review and meta-analysis to summarize effect of dietary acid load on blood pressure.

METHODS

A comprehensively search was performed in electronic databases including EMBASE, PubMed, Web of Science and Chinese National Knowledge Infrastructure. Summary ORs and their corresponding 95% CIs were computed assuming a randomized model or fixed model.

RESULTS

Ten publications comprising 4 cohort and 6 cross-sectional studies were eligible for meta-analysis. There were 8 studies about potential renal acid load (PRAL) and 4 about net endogenous acid production (NEAP). Essential hypertension was statistically associated with higher PRAL (OR = 1.14, 95% CI = 1.02-1.17). Our findings also demonstrated a positive impact of higher PRAL on elevating both diastolic pressure (WMD = 0.96, 95% CI = 0.67-1.26) and systolic pressure (WMD = 1.57, 95% CI = 1.12-2.03). A 35% increased risk of hypertension associated with higher NEAP was identified (OR = 1.35, 95% CI = 1.03-1.78).

CONCLUSIONS

The current study suggests that dietary acid load might be potential risk factor of hypertension.

Metabolic Syndrome Features: Is There a Modulation Role by Mineral Water Consumption? A Review

Metabolic syndrome (MetSyn) promotes, among others, the development of atherosclerotic cardiovascular disease and diabetes. Its prevalence increases with age, highlighting the relevance of promoting precocious MetSyn primary prevention and treatment with easy-to-implement lifestyle interventions. MetSyn features modulation through mineral water consumption was reviewed on Pubmed, Scopus and Google Scholar databases, using the following keywords: metabolic syndrome, hypertension, blood pressure (BP), cholesterol, triglycerides, apolipoprotein, chylomicron, very low-density lipoprotein, low-density lipoprotein, high-density lipoprotein (HDL), glucose, insulin, body weight, body mass index, waist circumference (WC), obesity and mineral(-rich) water. Twenty studies were selected: 12 evaluated BP, 13 assessed total-triglycerides and/or HDL-cholesterol, 10 analysed glucose and/or 3 measured WC. Mineral waters were tested in diverse protocols regarding type and composition of water, amount consumed, diet and type and duration of the study. Human and animal studies were performed in populations with different sizes and characteristics. Distinct sets of five studies showed beneficial effects upon BP, total-triglycerides, HDL-cholesterol and glucose. WC modulation was not reported. Minerals/elements and active ions/molecules present in mineral waters (and their pH) are crucial to counterbalance their inadequate intake and body status as well as metabolic dysfunction and increased diet-induced acid-load observed in MetSyn. Study characteristics and molecular/physiologic mechanisms that could explain the different effects observed are discussed. Further studies are warranted for determining the mechanisms involved in the putative protective action of mineral water consumption against MetSyn features.

Higher dietary acid load potentially increases serum triglyceride and obesity prevalence in adults: An updated systematic review and meta-analysis

Background

In the current meta-analysis, we aimed to systematically review and summarize the eligible studies evaluating the association between dietary acid load in terms of potential renal acid load (PRAL) and net-endogenous acid production (NEAP) with anthropometric parameters and serum lipids in adult population.

Methods

In a systematic search from PubMed, Scopus, Web of Sciences and Cochrane electronic databases up to December 2018, relevant studies were included. Cross-sectional, case control or cohort studies evaluating the association between PRAL and NEAP with the mean values of body mass index (BMI), waist circumference (WC), low and high density lipoprotein cholesterol (LDL, HDL), triglyceride (TG), total cholesterol (TC) and the prevalence of obesity were included.

Results

According to our results, having higher dietary acid load content in terms of high PRAL scores was associated with higher triglyceride concentrations (weighted mean difference (WMD): 3.468; confidence interval (CI): -0.231, 7.166, P = 0.04) and higher obesity prevalence (30% and 27% in highest versus lowest categories). Accordingly, being in the highest category of NEAP was associated with higher prevalence of obesity (25% and 22% in highest versus lowest category). In subgroup analysis, higher PRAL scores was associated with higher BMI in women (WMD: 0.122; CI: -0.001, 0.245; P = 0.049) and higher NEAP in men (WMD: 0.890; CI: 0.430, 1.350; P < 0.001). There was no association between dietary acid load and other studied parameters.

Conclusions

In the current meta-analysis, high dietary acid load content was associated with higher serum triglyceride concentrations and higher obesity prevalence. Reducing dietary acid load content might be a useful preventive strategy against obesity and metabolic disorders.

Dietary Acid Load: mechanisms and evidence of its health repercussions

Diet composition has long been known to influence acid-base balance by providing acid or base precursors. In general, foods rich in protein, such as meat, cheese, eggs, and others, increase the production of acid in the body, whereas fruit and vegetables increase alkalis. The capacity of acid or base production of any food is called potential renal acid load (PRAL). Diets high in PRAL induce a low-grade metabolic acidosis state, which is associated with the development of metabolic alterations such as insulin resistance, diabetes, hypertension, chronic kidney disease, bone disorders, low muscle mass and other complications. The aim of this paper is to review the available evidence which evaluates the association of the PRAL of the diet with the incidence of chronic diseases and metabolic disorders, as well as related mechanisms involved in their development.

Postulating the major environmental condition resulting in the expression of essential hypertension and its associated cardiovascular diseases: Dietary imprudence in daily selection of foods in respect of their potassium and sodium content resulting in oxidative stress-induced dysfunction of the vascular endothelium, vascular smooth muscle, and perivascular tissues

We hypothesize that the major environmental determinant of the expression of essential hypertension in America and other Westernized countries is dietary imprudence in respect of the consumption of daily combinations of foods containing suboptimal amounts of potassium and blood pressure-lowering phytochemicals, and supraphysiological amounts of sodium. We offer as premise that Americans on average consume suboptimal amounts of potassium and blood pressure-lowering phytochemicals, and physiologically excessive amounts of sodium, and that such dietary imprudence leads to essential hypertension through oxidative stress-induced vascular endothelial and smooth muscle dysfunction. Such dysfunctions restrict nitric oxide bioavailability, impairing endothelial cell-mediated relaxation of the underlying vascular smooth muscle, initiating and maintaining inappropriately increased peripheral and renal vascular resistance. The biochemical steps from oxidative stress to vascular endothelial dysfunction and its pernicious cardiovascular consequences are well established and generally accepted. The unique aspect of our hypothesis resides in the contention that Americans' habitual consumption of foods resulting in suboptimal dietary intake of potassium and supraphysiological intake of sodium result in oxidative stress, the degree of which, we suggest, will correlate with the degree of deviation of potassium and sodium intake from optimal. Because suboptimal intakes of potassium reflect suboptimal intakes of fruits and vegetables, associated contributors to oxidative stress include suboptimal intakes of magnesium, nitrate, polyphenols, carotenoids, and other phytochemical antioxidants for which fruits and vegetables contain abundant amounts. Currently Americans consume potassium-to-sodium in molar ratios of less than or close to 1.0 and the Institute of Medicine (IOM) recommends a molar ratio of 1.2. Ancestral diets to which we are physiologically adapted range from molar ratios of 5.0 to 10.0 or higher. Accordingly, we suggest that the average American is usually afflicted with oxidative stress-induced vascular endothelial dysfunction, and therefore the standards for normal blood pressure and pre-hypertension often reflect a degree of clinically significant hypertension. In this article, we provide support for those contentions, and indicate the findings that the hypothesis predicts.

Age-related Disease: A Revolution is Coming, Part 2-Dietary Acid Load, Hypertension, and Cardiovascular Disease

We are starting to develop the analytical tools to examine damage to our DNA and screen for the presence of clonal hematopoiesis of indeterminate potential. This type of technology will soon support the personalization of approaches to both the prevention and treatment of age-related diseases, which have historically been characterized as beyond our control. We are at the start of an era that will one day be looked upon as the age of precision personalized lifestyle health care. This article is the second in a series in which I will be examining new tools and research that I believe is paving the path forward and leading to exciting times ahead.