Dietary Acid Load, Serum Polychlorinated Biphenyl Levels, and Mortality Following Breast Cancer in the Long Island Breast Cancer Study Project

Dietary acid load (DAL) may be associated with all-cause mortality (ACM) and breast cancer-specific mortality (BCM), and these associations may be modified by serum polychlorinated biphenyl (PCB) levels. Participants included 519 women diagnosed with first primary in situ or invasive breast cancer in 1996/1997 with available lipid-corrected PCB data. After a median of 17 years, there were 217 deaths (73 BCM). Potential renal acid load (PRAL) and net endogenous acid production (NEAP) scores calculated from a baseline food frequency questionnaire estimated DAL. Cox regression estimated covariate-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between PRAL and NEAP with mortality. We evaluated effect measure modification by total serum PCB levels (>median vs. ≤median). PRAL quartile 4 versus quartile 1 was associated with an ACM HR of 1.31 (95%CI = 0.90–1.92). In the upper median of PCBs, ACM HRs were 1.43 (95%CI = 0.96–2.11) and 1.40 (95%CI = 0.94–2.07) for PRAL and NEAP upper medians, respectively. In the lower median of PCBs, the upper median of NEAP was inversely associated with BCM (HR = 0.40, 95%CI = 0.19–0.85). DAL may be associated with increased risk of all-cause mortality following breast cancer among women with high total serum PCB levels, but inversely associated with breast cancer mortality among women with low PCB levels.

Dietary Acid Load and Relationship with Albuminuria and Glomerular Filtration Rate in Individuals with Chronic Kidney Disease at Predialysis State

The Western diet, characterized by excessive consumption of animal protein and reduced intake of vegetables and fruits, is also rich in sulfur, chlorine, and organic acids, which are the main sources of dietary acid load. A relationship between dietary acid load, renal function, and progression of chronic kidney disease has been demonstrated. Dietary modifications seem to contribute to a reduction in dietary acid load, and are associated with improved outcomes in individuals with chronic kidney disease (CKD). The aim of this paper was to review the existing evidence concerning the association between dietary acid load and renal function in nondialyzed individuals with CKD. A systematic review was conducted by gathering articles in electronic databases (MEDLINE/PubMed, Scopus, and Web of Science) from January 2018 to May 2021. Dietary acid load and GFR and/or albuminuria were analyzed. A total of 1078 articles were extracted, of which 5 met the inclusion criteria. Only one study found no statistically significant associations between the study variables. The remaining showed a negative association between dietary acid load and renal function. This systematic review confirmed the existence of an association between dietary acid load and renal function, with a high dietary acid load contributing to a decreased renal function.

Dietary Acid Load and Glomerular Filtration Rate in Chronic Kidney Disease

Background: Kidney diseases are prevalencing rapidly. The nutritional transition has caused the diet of Iran community to increase the dietary acid load (DAL) and thus exacerbate metabolic disorders. Therefore, our goal was to determine the DAL of the diet in patients with Chronic Kidney Disease (CKD). Methods: In this cross-sectional study, the study population was composed of 90 patients with renal insufficiency. DAL was included of Potential Renal Acid Load(PRAL), Net EndogeneusAcid Production(NEAP) and Net Acid Excretion(NAE) that were extracted using data of food frequency questionnaire and their correlation with anthropometric and biochemical indices such as Glomerular Filtration Rate (GFR) and creatinine were analyzed by SPSS v.26 software with a significance level of < 0.05.Results: Mean of dietary acid load of participants were 17.15±9.85,-8.7±0.35 and 59.04±10.9 mEq/day for PRAL, NEAP and NAE respectively. Daily intake of energy (P<0.001) and protein percent of energy (P<0.01) in third tertile (T3) of PRAL were significant higher than first tertile (T1). Mean of age (P<0.05) and blood creatinine concentration (P<0.01) were significant higher in T1 than T1 of NEAP index and GFR was significant low (P<0.05). Daily energy intake (p<0.05), blood calcium concentration (p<0.05) and GFR (p<0.05) were significantly more in higher tertiles of NAE index. Based on Crude General linear model, the higher tertiles of PRAL compared to first tertile had significant lower GFR (P<0.05). In adjustment model, T3 group had more not significant GFR than T1 group. Only in model II adjustment, T2 group of NAE compared to T1, had higher GFR. Mean difference of GFR did not significant across tertiles of NEAP index. In case of Creatinine, based on model I adjustment, T3 group of NAE had more creatinine concentration than T1 group (P<0.01). T3 group of NEAP than T1 group had significant lower creatinine in crude and modelI adjustment (P<0.01). Discussion: Dietary Acid Load was associated with kidney function in CKD patients. In order to obtain logical results and to understand the cause-and-effect relationships, long-term studies with larger populations and consideration of blood factors such as blood bicarbonate are recommended.

Dietary Acid Load Is Positively Associated with the Incidence of Hyperuricemia in Middle-Aged and Older Korean Adults: Findings from the Korean Genome and Epidemiology Study

Hyperuricemia has been associated with a number of chronic diseases, such as type 2 diabetes mellitus, hypertension, and cardiovascular diseases. Dietary acid load plays a key role in regulating uric acid levels. We hypothesized that potential renal acid load (PRAL) and net endogenous acid production (NEAP) score would be positively associated with the incidence of hyperuricemia. Data from the Health Examinees study, a part of the Korean Genome and Epidemiology Study were used. The PRAL and NEAP scores were calculated to evaluate the dietary acid load. Hyperuricemia was defined as follows: >7.0 mg/dL and >6.0 mg/dL of serum uric acid levels in men and women, respectively. Multivariable Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the incidence of hyperuricemia. We identified 2500 new cases of hyperuricemia during a mean follow-up of 5.0 years (223,552 person years). The participants in the highest quartiles of the PRAL and NEAP score had 21% (HR: 1.21, 95% CI: 1.07–1.35, p for trend <0.0001) and 17% (HR: 1.17, 95% CI: 1.04–1.31, p for trend <0.0001) higher risks for hyperuricemia, respectively, than those in the lowest quartiles, after adjusting for covariates. In this prospective cohort study, a higher dietary acid load was positively associated with a higher incidence of hyperuricemia in Korean adults. This suggests that an alkaline diet may be an effective strategy to reduce the future risk of elevated uric acid levels.

A Vegan Diet Is Associated with a Significant Reduction in Dietary Acid Load: Post Hoc Analysis of a Randomized Controlled Trial in Healthy Individuals

The composition of diet strongly affects acid–base homeostasis. Western diets abundant in acidogenic foods (meat and cheese) and deficient in alkalizing foods (fruits and vegetables) increase dietary acid load (DAL). A high DAL has been associated with numerous health repercussions, including cardiovascular disease and type-2-diabetes. Plant-based diets have been associated with a lower DAL; however, the number of trials exploring this association is limited. This randomized-controlled trial sought to examine whether an isocaloric vegan diet lowers DAL as compared to a meat-rich diet. Forty-five omnivorous individuals were randomly assigned to a vegan diet (n = 23) or a meat-rich diet (n = 22) for 4 weeks. DAL was determined using potential renal acid load (PRAL) and net endogenous acid production (NEAP) scores at baseline and after 3 and 4 weeks, respectively. After 3 weeks, median PRAL (−23.57 (23.87)) and mean NEAPR (12.85 ± 19.71) scores were significantly lower in the vegan group than in the meat-rich group (PRAL: 18.78 (21.04) and NEAPR: 60.93 ± 15.51, respectively). Effects were mediated by a lower phosphorus and protein intake in the vegan group. Our study suggests that a vegan diet is a potential means to reduce DAL, whereas a meat-rich diet substantially increases the DAL burden.

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.

Associations between dietary acid load and obesity among Iranian women

Introduction: Diet-induced acid load may be associated with overweight and obesity as well as with diet quality. We aimed to study how dietary acid load is associated with overweight, obesity and diet quality indices in healthy women. Methods: We randomly selected 306 healthy 20 to 55 year-old women from health centers affiliated with Tehran University of Medical Science. They were enrolled in a cross-sectional study between June2016 and March 2017. Potential renal acid load (PRAL), net endogenous acid production (NEAP) and dietary acid load (DAL) were calculated for each person. Dietary quality index international (DQI-I),mean adequacy ratio (MAR), and energy density (ED) were estimated. Anthropometry was measured using standard protocols. Nutritional data were obtained from food frequency questionnaires (FFQ). We used multivariable logistic regression models to assess dietary acid load indices in relation to overweight, obesity and abdominal adiposity. Results: Participants had a mean age of 32.4 years. The number and percentage of women who were overweight, obese and who had abdominal obesity were 94(30.7), 38(12.4) and 126(41.2), respectively.The odds of obesity (adjusted odds ratio; Adj. OR = 2.41, 95% confidence interval; CI:1.01-5.74,P = 0.045) and abdominal adiposity (Adj. OR = 2.4, 95% CI:1.34-4.60, P = 0.004) increased significantly with tertile of DAL. Other dietary acid load indices (PRAL and NEAP) showed no significant association with obesity, overweight or abdominal obesity. As dietary acid load scores (PRAL, NEAP and DAL)increased, DQI-I and MAR significantly decreased whereas ED significantly increased across tertilesof dietary acid load indices (P < 0.001). Conclusion: Dietary acid load is associated with obesity and abdominal obesity and is also considered an indicator of diet quality.

Investigating the relationship between dietary acid load and risk of diabetes; a meta-analysis

Introduction: Diabetes is the most common endocrine disease that annually causes four million deaths in the world. It is not just a disease, however a series of metabolic disorders caused by defects in insulin secretion, insulin action, or both. Considering the importance of diet in the incidence and complications of diabetes, this study aimed to investigate the relationship between the dietary acid load with diabetes, which has recently been considered. Methods: This meta-analysis was first performed as a systematic review by searching in Google Scholar, Science Direct, PubMed, Wiley, Directory of Open Access Journals (DOAJ), Springer, Cochrane, ProQuest, and Scopus, as well as domestic databases including Magiran, SID, Irandoc, and Google Scholar. A total of 1511 articles were found that after reviewing and excluding irrelevant articles, five were included in the study. Results: In the present study, a significantly high heterogeneity was observed (I2 = 61.5, P = 0.01). A random effect model was used and the studies were weighted using the inverse-variance method. The odds ratio (OR) obtained from the meta-analysis was 1.17 (1.12-1.22). Examination of publication bias showed that the studies were symmetrically distributed in the funnel plot. Egger’s and Begg’s tests were also performed that showed no evidence for the existence of publication bias [Egger’s test (P ≥ 0.79) and Begg’s test (P ≥ 0.69)]. Conclusion: The results of the present meta-analysis showed a significant relationship between dietary acid load and the incidence of diabetes. This result is similar to most studies on the subject, except for one study, which was limited to the elderly male population. The number of studies in the present meta-analysis was low due to the limited number of research in this field.