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

Exploring new plant-based products: Acceptance of sunflower meal as a protein source in meat alternative products

In response to growing consumer demand for sustainable and plant-based food options, sunflower meal, a byproduct of oil extraction, emerges as a promising protein source. This study explores the potential of sunflower semi-defatted meal to create meat alternative mixes (MAMs) with a balanced nutritional profile and desirable sensory attributes. Two MAM formulations were developed: one incorporating toasted sunflower kernels (MAMk) and the other utilizing texturized protein sunflower (MAMt). Both formulations were enriched with tomato powder, spices, and a lipid matrix comprising sunflower, olive, and linseed oils. The doughs were shaped into mini-burger format and baked. Sensory evaluation revealed a preference for the MAMt formulation, which exhibited superior texture. Physical-chemical analysis confirmed MAMt's nutritional value, highlighting its high lipid (38.15 %) particularly monounsaturated fatty acids (41.98 % of the total lipid composition) and protein (20.10 %) content all essential amino acids (lysine limiting amino acid with 0.8 score). Moreover, MAMt demonstrated significant mineral content, especially iron, zinc, magnesium, and manganese (49 %, 68 %, 95 % and 89 %, respectivally, regarding recommended daily intake). While further refinement is necessary to optimize flavor, the study underscores the potential of sunflower meal to contribute to a more sustainable food system and provide consumers with a nutritious and appealing plant-based protein alternative.

High dietary acid load increases the risk of disability in women aged 75 years and older: A community-based cohort study

BACKGROUND

Metabolic acidosis caused by acidogenic diets increases muscle catabolism. High acidogenic diets can increase muscle loss in older adults; however, their association with functional outcomes remains unclear.

OBJECTIVES

To investigate whether high acidogenic diets increase the incidence of disability.

DESIGN

Longitudinal study.

SETTING

Community-based.

PARTICIPANTS

We included 1,704 community-dwelling Japanese individuals aged ≥ 75 years without disabilities at baseline (52.2 % females).

MEASUREMENTS

Baseline dietary acid load was assessed using potential renal acid load (PRAL) values, which reflect urinary acidity-with higher values indicating more acidogenic diets. The outcome measure was the one-year incidence of disability, defined as needing for long-term care or support based on certification by the Japanese long-term care insurance system. As the effects of PRAL are reportedly sex-specific, separate analyses were conducted for males and females. The participants were categorized into tertiles (T1-T3, with T1 as the reference) based on their PRAL values. Odds ratios (ORs) and 95 % confidence intervals (CIs) for outcome were calculated using multiple logistic regression analysis after adjusting for age, body mass index, living status, smoking status, hypertension, diabetes, dyslipidemia, energy intake, and alcohol intake.

RESULTS

The PRAL ranges in groups T1, T2, and T3 were: -64.51 to 0.21, 0.27 to 11.34, and 11.41 to 61.00, respectively, in males, and -61.22 to -3.84, -3.75 to 5.89, and 5.90 to 38.68, respectively, in females. Disabilities occurred in 44 (5.7 %) males and 71 (8.7 %) females. ORs (95 % CIs) for disability in T2 and T3 were 0.79 (0.35-1.76) and 0.81 (0.37-1.79), respectively, in males and 1.10 (0.57-2.13) and 1.96 (1.06-3.61), respectively, in females.

CONCLUSIONS

A high dietary acid load increased the incidence of disability in older females. Therefore, managing an acidogenic diet may help maintain daily living functions in older females. Future studies should investigate whether sex is an effect modifier.

Association of dietary acid load with inflammatory markers, oxidative stress, and clinical features in patients with knee osteoarthritis

Knee osteoarthritis (KOA) is a prevalent chronic condition characterized by inflammation and oxidative stress, particularly in individuals over 40. Dietary factors, specifically dietary acid load (DAL), may influence these pathological processes. However, the relationship between DAL and inflammatory markers, oxidative stress, and clinical features in patients with KOA remains unexplored. This cross-sectional study involved 147 participants aged 40 and above diagnosed with moderate to severe bilateral primary KOA. Dietary intake was assessed using a validated food frequency questionnaire, and DAL was quantified using Potential Renal Acid Load (PRAL) and Net Endogenous Acid Production (NEAP) indices. Clinical symptoms were evaluated using the WOMAC Index. Biochemical markers of oxidative stress and inflammation were measured from serum samples. Higher PRAL and NEAP scores were associated with increased levels of thiobarbituric acid reactive substances (TBARS) and total oxidant status (TOS), indicating elevated oxidative stress. Additionally, serum levels of inflammatory markers, including TNF-α and hs-CRP, positively correlated with higher DAL scores. Clinical assessments revealed that increased PRAL scores were related to greater severity of symptoms as measured by the WOMAC Index. This study demonstrates a significant association between dietary acid load and markers of inflammation and oxidative stress in KOA patients. These findings suggest that dietary modifications aimed at reducing acid load may serve as a beneficial adjunctive strategy in managing KOA and improving patient outcomes.

Relationship between TyG-BMI index and glycemic index with diet quality, anthropometric indices, and blood pressure in patients with metabolic syndrome

A recently introduced metric for assessing metabolic syndrome (MetS) is the triglyceride glucose-body mass index (TyG-BMI). Additionally, the glycemic index (GI) is recognized as a significant measure for evaluating conditions associated with blood glucose. In this context, our research explores the correlation between TyG-BMI and GI in relation to diet quality, anthropometric measurements, and blood pressure among individuals diagnosed with MetS. A cross-sectional descriptive-analytical study was conducted on 431 employees with MetS at Shiraz University of Medical Sciences (SUMS). Anthropometric measurements of height, weight, waist circumference (WC), and hip circumference (HC) were taken according to Persian cohort protocols. BMI, C-index, visceral adiposity index (VAI), body adiposity index (BAI), body shape index (ABSI), abdominal volume index (AVI), potential renal acid load (PRAL), TyG-BMI and GI were calculated. A physician measured blood pressure, while the dietary inflammatory index was determined using guidelines. Biochemical parameters were analyzed using standard laboratory techniques. Data analysis was conducted using SPSS software version 21, with a significance threshold set at <.05. A significant correlation was identified between the TyG-BMI index and the PRAL index (β = 0.094, P-value = .026), WC (β = 0.627, P-value < .001), BAI (β = 0.396, P-value < .001), and blood pressure (β = 0.063, P-value = .002). Furthermore, the findings indicated a notable association between the GI and blood pressure (β = 0.610, P-value < .001). The results of this study suggest that managing the PRAL index, body weight, and blood pressure may be associated with an enhanced status of TyG-BMI. Additionally, appropriate GI may be linked to regulated blood pressure. These findings can inform health-related policy decisions for these patients.

Improvement in symptoms of anxiety and depression in individuals with type 2 diabetes: retrospective analysis of an intensive lifestyle modification program

BACKGROUND

Type 2 diabetes (T2D) is a chronic metabolic disorder that has a notable influence on mental well-being, contributing to elevated morbidity and mortality rates. Depression and anxiety disorders are the most common mental health concerns among patients with T2D worldwide. Therefore, the present study aimed to assess the impact of an online intensive lifestyle intervention (ILI) on mental health outcomes (depression and anxiety) in patients with T2D in India.

MATERIALS AND METHODS

This retrospective pre-post analysis included adult patients (aged > 18 years) diagnosed with T2D who were enrolled in a diabetes management program in India between June 2021 and June 2023. The intervention consisted of lifestyle modifications such as a customized plant-based diet, regular physical activity, psychological support through group and individual therapy, and medical management. Data were extracted from the electronic database of the clinic, including anthropometry, medical history, biochemical parameters, symptoms of depression, and anxiety (assessed using the Patient Health Questionnaire-9 (PHQ-9) and Generalized Anxiety Disorders-7 (GAD-7) scale) at the start and end of the six-month intervention period.

RESULTS

Of the 1061 eligible patients (177 with prediabetes), 40.3% were female. The mean age, duration of diabetes, and HbA1c levels were 52 ± 10.4 years, 9.8 ± 7.8 years, and 8 ± 1.7%, respectively. The prevalence of symptoms of depression and anxiety (ranging from mild to severe) was 46% and 44.3%, respectively, which reduced to 28.7% and 29.2%, respectively, post-intervention.

CONCLUSION

Integrated ILI successfully improved the symptoms of anxiety and depression, highlighting the importance of a multidisciplinary approach that includes diet, physical activity, psychological support, and medical management in enhancing mental health outcomes among patients with T2D. Future prospective studies are needed to explore the long-term effects of such interventions and develop effective strategies for promoting mental health in diverse populations.

TRIAL REGISTRATION

The study was approved by the Freedom from Diabetes Research Foundation Institutional Ethics Committee (approval number FFDRF/IEC/2024/7) and registered in the Clinical Trials Registry of India (CTRI/2024/03/064596, registered on March 21, 2024).

An unbiased, sustainable, evidence-informed Universal Food Guide: a timely template for national food guides

BACKGROUND

Although national food guides are designed, ostensibly, to translate scientific evidence with respect to food, dietary patterns, and health, their development has increasingly become a corporate/political process as well as scientific one; often with corporate/political influences overriding science. Our aim was to construct an unbiased, sustainable, evidence-informed Universal Food Guide to serve as a template for countries to develop their unique guides, thereby, provide a valid resource for health professionals, health authorities, and the public.

METHODS

To address our aim, we conducted an integrative review of multiple evidence-informed sources (e.g., established databases, evidence syntheses, scholarly treatises, and policy documents) related to four areas: 1. Food guides' utility and conflicts of interest; 2. The evidence-based healthiest diet; 3. Constituents of the Universal Food Guide template; and 4. Implications for population health; regulation/governance; environment/climate/planetary health; and ethics.

RESULTS

The eating pattern that is healthiest for humans (i.e., most natural, and associated with maximal health across the life cycle; reduced non-communicable disease (NCD) risk; and minimal end-of-life illness) is whole food, low fat, plant-based, especially vegan, with the absence of ultra-processed food. Disparities in national food guide recommendations can be explained by factors other than science, specifically, corporate/political interests reflected in heavily government-subsidized, animal-sourced products; and trends toward dominance of daily consumption of processed/ultra-processed foods. Both trends have well-documented adverse consequences, i.e., NCDs and endangered environmental/planetary health. Commitment to an evidence-informed plant-based eating pattern, particularly vegan, will reduce risks/manifestations of NCDs; inform healthy food and nutrition policy regulation/governance; support sustainable environment/climate and planetary health; and is ethical with respect to 'best' evidence-based practice, and human and animal welfare.

CONCLUSION

The Universal Food Guide that serves as a template for national food guides is both urgent and timely given the well-documented health-harming influences that corporate stakeholders/politicians and advisory committees with conflicts of interest, exert on national food guides. Such influence contributes to the largely-preventable NCDs and environmental issues. Policy makers, health professionals, and the public need unbiased, scientific evidence as informed by the Universal Food Guide, to inform their recommendations and choices.

The potential renal acid load of plant-based meat alternatives

Plant-based meat alternatives (PBMAs) are food products derived from plants and designed to mimic the preparation methods, nutritional profile, and sensorial qualities of meat. PBMAs are currently subject to a controversial debate concerning their health value. Here, we reviewed PBMAs' potential renal acid load (PRAL). The PRAL is an estimate for the amount of acid or base a certain food produces in the human body, and was associated with tissue damage and acid stress. PRAL values varied substantially across the examined foods, and differences were as large as 19.73 mEq per 100 g of PBMA. Mycoprotein- and wheat-based PBMAs were more acidic than conventional meats. The majority of items, however, exerted a lower PRAL to the human kidneys when compared to their meat-based counterparts. Our findings reiterate that not all PBMAs are created equal, and suggest that PBMAs are generally not suitable to substantially alkalize an individual's diet.

Dietary acid load as well as dietary phytochemical index, and association with multiple sclerosis: results from a case-control study

INTRODUCTION

Multiple sclerosis (MS) is a chronic inflammatory disease characterized by central nervous system (CNS) lesions. Although the etiology and pathogenesis of MS remains unclear, nutrition is among the environmental factors that may be involved in developing MS. Currently, no specific diet has been associated with MS. This study aimed to investigate the relationship between the dietary phytochemical index (DPI), dietary acid load (DAL), and the risk of developing MS.

METHODS

This case‒control study was conducted on 174 patients with MS and 171 healthy individuals in Mashhad, Iran. Data were collected using a 160-item semiquantitative food frequency questionnaire (FFQ). The study investigated the association between DPI, DAL, and MS, considering anthropometric measures, dietary intake, smoking habits, and sex. DPI, potential renal acid load (PRAL), and net endogenous acid production (NEAP), as indicators of DAL, were calculated based on the FFQ.

RESULTS

The study analyzed 345 participants, comprising 174 (50.4%) MS patients and 171 (49.6%) healthy individuals. The mean age of the participants was 32.45 ± 8.66 years. The DPI score was significantly lower among MS patients, while the NEAP and PRAL scores were significantly higher among MS patients compared to the healthy group. There was no relationship between NEAP (OR 1.001; 95% CI 0.959-1.044; P = 0.974) and PRAL (OR 1.019; 95% CI 0.979-1.061; P = 0.356) and MS incidence.

CONCLUSIONS

The study found higher smoking and obesity rates in MS patients, with a reduced DPI score and increased DAL. Further studies are needed before recommending plant-based foods and dietary acid-base balance evaluation as therapeutic approach.

Microbiome Taxonomic and Functional Differences in C3H/HeJ Mice Fed a Long-Term High-Fat Diet with Beef Protein ± Ammonium Hydroxide Supplementation

Studies have suggested that alkalinized foods may reduce the effects of the acidogenic Western diet in promoting obesity, metabolic syndrome, type 2 diabetes, cancer, and coronary heart disease. Indeed, a recent study in mice fed a high-fat diet containing dietary beef supplemented with ammonium hydroxide showed improvement in a suite of metabolic outcomes. However, the effects of dietary protein ammonium supplementation on the microbiome remain unknown. In this study, the effects of ammonium supplementation on beef protein towards microbiome taxa and function in a high-fat diet were analyzed. Fecal microbiomes were characterized using a shotgun metagenomic approach for 16-month-old male and female mice after long-term diet treatments. The results for ammoniated diets showed that several bacteria known to be associated with health benefits increased significantly, including Romboutsia, Oscillospiraceae, and Lactococcus cremoris. The beneficial mucin-degrader Akkermansia was especially abundant, with a high prevalence (~86%) in females. Concurrently, the phyla Actinomycetota (Actinobacteria) and Bacteroidota (Bacteroidetes) were significantly reduced. While sex was a confounding factor affecting microbiome responses to ammonium supplementation in dietary protein, it is worth noting that several putatively beneficial microbiome functions increased with ammonium supplementation, such as glycine betaine transport, xenobiotic detoxification, enhanced defense, and others. Conversely, many disease-associated microbiome functions reduced. Importantly, modifying protein pH alone via ammonium supplementation induced beneficial microbiota changes. Taken together, these results suggest that ammonium-supplemented proteins may mediate some negative microbiome-associated effects of high-fat/Western diets.

Citrate-based dietary alkali supplements available in Germany: an overview

BACKGROUND

Fruits and vegetables are abundant in alkali precursors and effectively reduce the Potential Renal Acid Load (PRAL) from diet. Oral alkali supplements are supposed to exert comparable alkalizing effects on the human body, and have been shown to beneficially affect bone and kidney health. A comparative analysis of the available dietary alkali supplements in Germany was performed, contrasting their potential PRAL-lowering potential.

METHODS

We reviewed the currently available dietary citrate-based alkali supplements sold in Germany with a special focus on their mineral content, their PRAL-lowering potential and other characteristics inherent to each product. Supplements containing either potassium-, calcium- or magnesium citrate or any combination of these organic salts were reviewed. The total alkali load (TAL) was calculated based on the recommended daily dosage (RDD).

RESULTS

Sixteen supplements with a mean alkali powder content of 220.69 ± 111.02 g were identified. The mean magnesium content per RDD was 239.93 ± 109.16 mg. The mean potassium and median calcium content were 550 ± 325.58 mg and 280 (240) mg, respectively. Median TAL was 1220 (328.75) mg. The PRAL-lowering potential from a single RDD ranged from - 51.65 mEq to -8.32 mEq. Substantial price differences were found, and the mean price of the examined supplements was 16.67 ± 5.77 Euros. The median price for a 1 mEq PRAL-reduction was 3.01 (3.14) cents, and ranged from 0.77 cents to 10.82 cents.

CONCLUSIONS

Noticeable differences between the identified alkali supplements were encountered, warranting an individual and context-specific approach in daily clinical practice.

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.

Quantifying the potential renal acid load of edible mushrooms

The capability of any food to alter net endogenous acid or base production can be estimated using the potential renal acid load (PRAL) estimation method. The PRAL of edible mushrooms has been rarely examined; thus a quantification study of n = 37 edible mushroom species was performed. Results revealed a heterogeneous picture: although the most commonly consumed mushrooms (e.g., Agaricus bisporus, Lentinula edodes, and Pleurotus ostreatus (white)) have alkalizing properties, several acidifying species (Volvariella volvacea, Pleurotus flabellatus) were identified, which may be attributable to their high phosphorus content.

A Therapeutic Approach in the Management of Chronic Kidney Disease: Plant-Based Dietary Models and Associated Parameters

PURPOSE OF REVIEW

Chronic kidney disease is one of the leading causes of death worldwide today. Nutrition and nutrition-related factors have a very important role in both the prevention and management of the disease. Plant-based dietary practices are one of the promising approaches to chronic kidney disease. This review aims to examine the potential benefits and risks of plant-based diet models on symptoms and indices used in diet quality in chronic kidney disease.

RECENT FINDINGS

Recently, a growing body of evidence has shown that, unlike animal-based diets, diets rich in plant-based nutrients may play an active role in the incidence of chronic kidney disease in many ways and the management of common symptoms, such as metabolic acidosis, uremic toxicity, and hyperphosphatemia. Implementation of existing plant-based dietary patterns in patients with chronic kidney disease may increase the efficacy of the diet and improve patients' quality of life by expanding their food choices. While there are concerns about creatine deficiency, dietary adequacy, and accessibility regarding plant-based diets, available information is limited.

Elevated Inflammation and Poor Diet Quality Associated with Lower eGFR in United States Adults: An NHANES 2015-2018 Analysis

Chronic kidney disease is prevalent within the United States likely due to dietary habits. The purpose of this study was to examine the relationship between the high-sensitivity c-reactive protein (hs-CRP) and diet quality (DQ) and their effect on the eGFR. A cross-sectional secondary data analysis study was conducted among adults (n = 6230) using NHANES 2015-2018 data. DQ was determined by the Healthy Eating Index-2015 (HEI-2015). Multivariable linear regressions were conducted based on eGFR (≥90 or <60 mL/min/1.73 m2) after adjustments for age, race/ethnicity, hypertension, diabetes mellitus, cardiovascular disease, and kidney disease awareness. All analyses were performed in SAS version 9.4 with a statistical significance of p < 0.05. Results showed that participants who had an eGFR of <60 mL/min/1.73 m2 were older and had a higher prevalence of hypertension and diabetes and had higher hs-CRP compared to participants with an eGFR ≥ 90 (p < 0.005). Of participants with an eGFR < 60, 27% reported that they were aware they had kidney disease. Regardless of the eGFR at baseline, there was a negative interaction effect on the DQ scores and hs-CRP on the eGFR (p < 0.05). Independently, for participants with an eGFR < 60, their DQ scores had a positive significant relationship on their eGFR (p = 0.03), whereas their hs-CRP had a negative significant relationship on thier eGFR (p < 0.001). For participants with an eGFR < 60, age, hypertension, and kidney disease awareness influenced this relationship (p < 0.001). Overall, low DQ and elevated hs-CRP contributed to a reduction in kidney function. Efforts to improve dietary intake and strategies to reduce inflammation and improve kidney function are necessary.

The association of diet-dependent acid load with colorectal cancer risk: a case-control study in Korea

Acid-base disequilibrium is a contributor to cancer development because it affects molecular activities such as insulin-like growth factor 1 levels and adiponectin production. However, evidence of an association of diet-induced acid-base imbalance with colorectal cancer (CRC) is limited. We examined whether colorectal carcinogenesis is attributable to a diet with a high acid load. We recruited a total of 923 CRC cases and 1846 controls at the National Cancer Center in Korea for inclusion in a case-control study. We collected information on nutrient intake and specific clinical parameters of CRC by using a semiquantitative FFQ and medical records, respectively. Potential renal acid load (PRAL) and net endogenous acid production (NEAP) were used to estimate diet-dependent acid load. We used an unconditional logistic regression model to analyse the association. Dietary acid load scores had a positive association with the odds of CRC (OR = 2·31 (95 % CI 1·79, 2·99) and OR = 2·14 (95 % CI 1·66, 2·76) for PRAL and NEAP, respectively, Pfor trend < 0·001). A stronger positive association was observed for females (OR = 3·09, 95 % CI 1·93, 4·94) than for males (OR = 1·71, 95 % CI 1·27, 2·31). Furthermore, acidogenic diets appeared to affect rectal cancer more strongly than colon cancer in females. Our study contributes to reinforcing epidemiological evidence regarding a detrimental effect of acidogenic diets on colorectal carcinogenesis. Thus, it is important to pay attention to the balance of acidogenic (e.g. poultry and red meat) and alkalinogenic foods (e.g. fruits and vegetables) in CRC prevention, especially for females.

Dietary acid load decreases with age and is associated with sagittal abdominal diameter: a nationally representative quantification study in US adults

BACKGROUND

Dietary acid load (DAL) has been associated with frailty and hip fractures in older adults, who often have a reduced kidney function and thus compromised buffering capacities. Studies to quantify DAL in older adults are scarce and controversies persist as to whether DAL in- or decreases with age.

AIM

To enhance the understanding of DAL in older individuals, we examined its relationship with increasing age and selected anthropometric data in a well-characterized sample of US adults.

METHODS

Secondary data analysis of nationally representative data from the National Health and Nutrition Examination Surveys data (NHANES 2011-2016). The sample included n = 3018 adults aged 60+, which may be extrapolated to represent n = 45,113,471 Americans. DAL was estimated using 4 formulas, including Potential Renal Acid Load (PRAL) and Net Endogenous Acid Production (NEAP).

RESULTS

All employed DAL scores tended to decline with increasing age. Participants aged 80 years or older yielded the lowest DAL scores. The average US citizen aged 60+ consumed an acidifying diet, yet there were sex-specific differences in the adjusted means for some scores. NEAP was positively correlated with both body mass index (r = 0.26, p < 0.001) and the sagittal abdominal diameter (r = 0.31, p < 0.001) in this nationally representative sample.

CONCLUSION

The previously reported phenomenon of increasing DAL values in older people in non-Western countries may not apply to the US. Our findings may constitute an important step towards a better understanding of DAL in older US adults, and highlight the need for additional population-specific research in the field.

The Role of Plant-Based Diets in Preventing and Mitigating Chronic Kidney Disease: More Light than Shadows

Chronic kidney disease (CKD) is a non-communicable disease that affects >10% of the general population worldwide; the number of patients affected by CKD is increasing due in part to the rise in risk factors such as obesity, hypertension, and diabetes mellitus. As many studies show, diet can be an important tool for preventing and mitigating the onset of non-communicable diseases. Plant-based diets (PBDs) are those that emphasize the consumption of plant foods and may or may not include small or moderate amounts of animal foods. Recently, these diets have received increasing interest because they have been associated with favourable effects on health and also appear to protect against the development and progression of CKD. PBDs, which are associated with protein restrictions, seem to offer adjunctive advantages in patients with chronic kidney disease, as compared to conventional low-protein diets that include animal proteins. The principal aims of this review are to provide a comprehensive overview of the existing literature regarding the role of plant-based diets and low-protein, plant-based diets in the context of chronic kidney disease. Moreover, we try to clarify the definition of plant-based diets, and then we analyse possible concerns about the use of PBDs in patients with chronic kidney disease (nutritional deficiency and hyperkalaemia risk). Finally, we offer some strategies to increase the nutritional value of plant-based low-protein diets. In the Materials and Methods section, many studies about plant-based diets and low-protein plant-based diets (e.g., the very-low-protein diet and vegan low-protein diet, LPD) in chronic kidney disease were considered. In the Results and Conclusion section, current data, most from observational studies, agree upon the protective effect of plant-based diets on kidney function. Moreover, in patients with advanced CKD, low-protein plant-based options, especially a very-low-protein diet supplemented with heteroanalogues (VLPDs), compared to a conventional LPD appear to offer adjunctive advances in terms of delaying dialysis and mitigating metabolic disturbances. However, further studies are necessary to better investigate the possible metabolic and cardiovascular advantages of plant-based LPDs versus conventional LPDs.

The Role of Hemp (Cannabis sativa L.) as a Functional Food in Vegetarian Nutrition

Recently, there has been a renewed interest in Cannabis sativa and its uses. The recreational use of inflorescences as a source of THC has led to the legal restriction of C. sativa cultivation to limit the detrimental effects of psychotropic substance abuse on health. However, this has also limited the cultivation of textile/industrial varieties with a low content of THC used for textile and nutritional purposes. While previously the bans had significantly penalized the cultivation of C. sativa, today many countries discriminate between recreational use (marijuana) and industrial and food use (hemp). The stalks of industrial hemp (low in psychotropic substances) have been used extensively for textile purposes while the seeds are nutritionally versatile. From hemp seeds, it is possible to obtain flours applicable in the bakery sector, oils rich in essential fatty acids, proteins with a high biological value and derivatives for fortification, supplementation and nutraceutical purposes. Hemp seed properties seem relevant for vegetarian diets, due to their high nutritional value and underestimated employment in the food sector. Hemp seed and their derivatives are a valuable source of protein, essential fatty acids and minerals that could provide additional benefit to vegetarian nutrition. This document aims to explore the information available in the literature about hemp seeds from a nutritional point of view, highlighting possible beneficial effects for humans with particular attention to vegetarian nutrition as a supplemental option for a well-planned diet.

The 1995 potential renal acid load (PRAL) values may no longer adequately reflect the actual acid-base impact of certain foods: A hypothesis

Background: In 1995, Remer and Manz reported potential renal acid load (PRAL) values of various foods, quantifying their estimated impact on acid-base balance. Their estimation considered ionic dissociation, sulphur metabolism and intestinal absorption rates for several micronutrients and proteins. Notably, PRAL values are based on food content data from the early 1990s and may nowadays no longer adequately reflect accurate estimates. Some foods' macronutrient and mineral content has declined over the past three decades due to changes in soil mineral health. Aim: We hypothesize that the 1995 PRAL values no longer adequately reflect reliable estimates of the current acid-base impact of some foods. Methods: Based on specific examples, we argue that these values overestimate the alkalizing effects of various fruits and vegetables. Conclusion: Discussing evidence in favour of (and against) our hypothesis, we conclude that the 1995 PRAL estimates should nowadays rather be used as a relative guidance and reviewed carefully.

Dietary Acid Load and Cancer Risk: A Review of the Uruguayan Experience

Dietary acid load (DAL) is recognized as a risk factor for several chronic disorders, including obesity, diabetes, and osteoporosis. Recent evidence suggests that an elevated DAL, as measured by the validated potential renal acid load (PRAL) and net endogenous acid production (NEAP) scores, could also increase the risk for several cancers. This narrative review summarizes the potential role of DAL in Uruguayan cancer patients and outlines the potentially involved pathophysiological pathways that mediate the role of DAL in both cancer development and growth. Although Uruguay is a developing country, its average diet is a heavily meat-based Western one, translating into a supraphysiological acid burden from diet. In recent years, we have published epidemiologic evidence based on ten case-control studies involving 3736 cancer cases and 9534 hospital-based controls. Odds ratios and 95% confidence intervals were estimated for each interest variable to analyze the association between the exposure levels of DAL scores and cancer, calculated by unconditional logistic regression. In a majority of the cases, the highest DAL scores tended to double the cancer risk as compared to the lowest category. We also found high risks for methionine intake, an acidifying amino acid found in higher concentrations in animal-based foods, which may increase cancer risks at least by a joint action based on the pH and the proliferation enhancing properties of the amino acid itself.

Dietary Acid Load Is Not Associated with Serum Testosterone in Men: Insights from the NHANES

The dietary acid load (DAL) is a novel marker of overall diet quality, which has been associated with overweight, type 2 diabetes and altered glucocorticoid secretion. A potential association with sex hormones is thus not inconceivable. We investigated whether DAL was associated with serum total testosterone concentrations of men in the National Health and Nutrition Examination Survey. The DAL scores, including the potential renal acid load (PRAL) and net endogenous acid production (NEAP), were estimated and compared between participants with low and normal testosterone levels. The investigated sample encompassed n = 377 males with a mean age of 49.50 years. Approximately 73% of the sample were of Non-Hispanic White origin. None of the examined DAL scores showed significant associations with serum testosterone levels. We observed no significant differences in the crude DAL scores between individuals with low testosterone levels and individuals with normal testosterone levels. Multivariate regression models adjusting for covariates confirmed the lack of associations between the PRAL and serum testosterone. Our results are of particular importance for those individuals who wish to lower their DAL in light of the presumable health effects of a more alkaline diet. Our data suggest that diet modifications toward a lower intake of animal protein and refined grains (which consecutively translates into a lower DAL) may not negatively affect men's testosterone levels.

Dietary Acid Load Correlates with Serum Amino Acid Concentrations after a Four-Week Intervention with Vegan vs. Meat-Rich Diets: A Secondary Data Analysis

Chronic low-grade metabolic acidosis is now a common phenomenon in the Western world. The high dietary intake of sulfur-containing amino acids in the form of processed meats results in an excessive release of acid in the form of protons and non-metabolizable acidic anions. The kidneys produce increasing amounts of ammonia to excrete this acid. This process requires the breakdown of the nitrogenous amino acid glutamine, which the body provides by breaking down muscle tissue. Hitherto not examined, we hypothesized that a high dietary acid load (DAL) could alter the serum concentrations of selected amino acids. Using secondary data from a 4-week dietary intervention study conducted in 2017, we examined the associations between various amino acids and DAL in n = 42 individuals who either consumed a meat-rich or vegan diet. Results from this secondary data analysis suggested that DAL (as measured by the potential renal acid load and net endogenous acid production) is positively correlated with higher serum concentrations of lysine and 1-methyl-histidine (r = 0.50 and 0.43, respectively) and negatively correlated with glutamine and glycine (r = -0.43 and -0.47, respectively). The inverse association with glycine and glutamine warrants special attention, as both play an important role in many metabolic disorders and the immune system.

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.

The association of dietary acid load (DAL) with estimated skeletal muscle mass and bone mineral content: a cross-sectional study

BACKGROUND & AIMS

Dietary patterns that promote mild metabolic acidosis may have a negative effect on bone and muscle, and a high dietary acid load (DAL) may be detrimental to skeletal muscle mass and bone mineral content. However, the association between skeletal muscle mass and bone mineral content with dietary acid load has not been consistently reported in previous studies. The objective of the study was to evaluate the association of potential renal net acid load (PRAL) and net endogenous acid production (NEAP) with bone mineral content and skeletal muscle mass in pre-menopause women with overweight or obesity in Iran.

METHOD

Three hundred and ninety women with a body mass index (BMI) of 25 were included in this cross-sectional study. We used a validated 147-item semi-quantitative food frequency questionnaire (FFQ) for evaluating the dietary intake. Based on the dietary data, potential renal net acid load (PRAL) and net endogenous acid production (NEAP) were calculated. Muscle mass and bone mineral content were estimated by a bioelectrical impedance analyzer (BIA).

RESULTS

After controlling for potential confounders, we discovered a significant linear relationship between PRAL (β = -0.027, 95%CI = -0.049 to -0.004, P = 0.02) and NEAP (β = -0.05, 95%CI = -0.097 to -0.003, P = 0.03) and skeletal muscle mass index. However, there was no significant difference between SMM and BMC across PRAL and NEAP tertiles.

CONCLUSION

PRAL and NEAP were found to be inversely related to skeletal muscle mass index among overweight/obese women. Further research is required to establish whether this relationship is important for musculoskeletal health in these populations.

How Well Do Low-PRAL Diets Fare in Comparison to the 2020-2025 Dietary Guidelines for Americans?

The regular consumption of net acid-producing diets can produce "acid stress" detrimental to human health. Alkalizing diets characterized by a negative potential renal acid load (also called low-PRAL diets (LPD)) enjoy uninterrupted popularity. However, the nutritional adequacy of said diets has rarely been assessed in large populations. Using data from the National Health and Nutrition Examination Surveys, we estimated nutrient intake in individuals consuming an LPD and contrasted the results in an age- and sex-specific manner to individuals on an acidifying diet (high-PRAL diet, HPD). Both groups were compared with the daily nutritional goals (DNG) specified in the 2020-2025 Dietary Guidelines for Americans (DGA). Our analysis included 29,683 individuals, including 7234 participants on an LPD and 22,449 participants on an HPD. Individuals on an LPD numerically met more nutritional goals than individuals on an HPD, yet both failed to meet the goals for several nutrients of public health concern (vitamin D and calcium). As opposed to individuals on an HPD, LPD consumers met the DGA recommendations for saturated fat and potassium. Individuals on an LPD consumed significantly more fiber than individuals on an HPD, as well as yielded a more favorable potassium-to-sodium intake ratio.