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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.

The changing diets accompanying our modern life style have increased the content of foods that form acidic metabolic waste residues in the body. Wastes from these metabolic processes are released into the interstitial fluids and the blood, slightly changing their pH temporarily. This link may in turn have an impact on the incidence of non-communicable diseases (NCDs). According to Warburg effect theory, an acidic cellular and circulatory environment may cause various specific health problems such as hypoxia and cancer, whereas an oxygen-rich optimum-alkaline environment could retain healthy cells. However, the mechanisms by which the diet may be influential on blood pH-related parameters and on health have remained largely unknown. This paper begins with a detailed presentation of the concepts, issues and the existing evidence regarding alkaline and acid forming diets, and summarizes the three main mechanisms by which the diet influences the acid-base balance in the body. It then presents the findings of a small exploratory study in which one author (HB) followed diets traditionally thought to produce alkaline or acidic residues. After each diet period of one month (with a two-month wash out period), pH, oxygen saturation, and carbon dioxide partial pressure were measured for arterial and for venous blood. The resulting data indicated that the diets followed changed blood pH-related parameters in the expected directions according to the acid-base theory of health. Increased intake of acid-forming foods resulted in a slightly lower pH level, but a significant reduction of oxygen saturation in the blood, whereas increased consumption of alkaline forming foods maintained the high oxygen saturation in the blood that, according to Warburg effect theory, may, if maintained, reduce the incidence of NCDs. Further cross-over research of this kind is needed, utilizing large samples and testing various dietary modifications.

Currently, alkaline nutritional therapy has raised great discussion in the scientific environment as a factor of renal protection. In order to determine the level of scientific evidence on the influence of diet and alkaline water on the reduction of complications in chronic kidney disease, a review of literature was carried out in six databases: BIREME Virtual Health Library (BVS), PubMed , Web of Science (WoS), SCOPUS and Cochrane Library, using the following keywords: alkaline water, chronic kidney disease / chronic kidney insufficiency, alkaline diet, fruit, vegetables, glomerular filtration rate, potential renal acid load. A total of 1071 references were found. Excluding the duplicates and selecting the articles that deal specifically with the theme, it had totalized 34 articles. After selecting the articles and classifying the type of study, the level of scientific evidence of the articles was determined according to Hood. The studies selected by this review consider that alkaline diets based on fruits and vegetables and the administration of bicarbonate can interfere in the complications of Chronic Renal Disease, such as reducing metabolic acidosis and maintaining the glomerular filtration rate, without being able to find the role of alkaline mineral water in this outcome. However, only 27% of the studies presented more than five scientific evidence, on a scale of one to ten, where ten has the highest scientific evidence and one the lowest. These data point us to the need for more studies with better designs, larger samples, without biases and conflicts of interest. Atualmente, a terapia nutricional alcalina tem suscitado grande discussão no meio científico, como fator de proteção renal. Com o objetivo de determinar o nível de evidência científica dos trabalhos publicados sobre a influência da dieta e água alcalina na redução de complicações na doença renal crônica, foi realizada revisão de literatura em seis bases de dados: Biblioteca Virtual em Saúde (BVS) da BIREME, PubMed, Web of Science (WoS), SCOPUS e Cochrane Library, utilizando as seguintes palavras-chave: água alcalina, doença renal crônica, dieta alcalina, frutas, verduras, taxa de filtração glomerular, carga potencial de ácido renal. Foram encontradas 1071 referências. Excluindo as duplicatas e selecionando os estudos que tratassem especificamente a temática, totalizaram 34 artigos. Após a seleção dos artigos e classificação quanto ao tipo de estudo foi determinado o nível de evidência científica dos artigos, segundo Hood. Os estudos selecionados por esta revisão consideram que as dietas alcalinas a base de frutas e verduras e a administração de bicarbonato podem interferir nas complicações da Doença Renal Crônica, como redução da acidose metabólica e manutenção da taxa de filtração glomerular, sem ter sido possível encontrar o papel da água mineral alcalina nesse desfecho. Entretanto, apenas 27% dos estudos apresentaram evidência científica superior a cinco, em uma escala de um a dez, em que dez apresenta maior evidência científica e um a menor. Esses dados nos remetem a necessidade de mais estudos com melhores desenhos, maiores casuísticas, sem vieses e conflitos de interesse.

Diet plays a pivotal role in shaping the trajectory of chronic diseases. In this regard, the Mediterranean diet has been widely shown to exert beneficial effects on cardiometabolic health. On the contrary, the Western diet, which has also been reported to be an acidogenic dietary pattern, elicits detrimental effects on both metabolic and cardiovascular (CV) health. However, the role of dietary acid load (DAL) as a predictor of cardiometabolic prognosis remains to be elucidated. Thus, this study aims to compare Mediterranean diet adherence (MDA) and DAL focusing on their relationship with metabolic and CV prognosis. A total of 448 individuals aged 55–80 years were grouped depending on their MDA, assessed using food frequency questionnaires, or DAL, evaluated using potential renal load acid (PRAL) and net-endogenous acid production (NEAP). Study participants underwent anthropometric and biochemical measurements. The metabolic syndrome (MetS) prevalence was evaluated according to the National Cholesterol Education Program-Adult Treatment Panel III. Finally, the CV risk was evaluated using three independent algorithms: atherosclerotic cardiovascular disease (ASCVD), European Systematic COronary Risk Evaluation (SCORE), and Cuore risk scores. Mediterranean diet adherence was negatively associated with PRAL and NEAP. Individuals in the higher MDA tertile group had higher HDL cholesterol as well as lower homeostasis model assessment index (HOMA-IR) and fat mass relative to the lowest MDA tertile. However, in the high-MDA tertile group, there was neither a significantly lower MetS prevalence nor CV risk. Instead, both the MetS prevalence and CV risk were higher in individuals in the higher acid PRAL quartile relative to the lower alkaline PRAL quartile. Dietary acid load, especially assessed using PRAL but not MDA, was associated with indices of metabolic and CV prognosis. Thus, DAL assessed by 24-h dietary recalls may represent a better predictor of cardiometabolic health if compared to MDA evaluated using food frequency questionnaires.

Kidneys produce bicarbonate ions that neutralize acids in the blood. Patients suffering from Chronic Kidney Disease (CKD) often present metabolic acidosis, as the kidney can no longer neutralize the acid load. Alkaline diet based on fruits, vegetables and mostly plant protein may have a positive effect on long-term preservation of the renal function in patients with stage 4-5 CKD while maintaining the nutritional status.

The acidic tumor microenvironment is associated both with the progression and drug resistance of cancer. We aimed to investigate the effects of alkalization therapy performed concurrently with chemotherapy on the survival of advanced pancreatic cancer patients (study registration: UMIN 000035659).Twenty-eight patients with metastatic or recurrent pancreatic cancer were assessed in this study. Alkalization therapy consisted of an alkaline diet with supplementary oral sodium bicarbonate (3.0-5.0 g/day).The mean urine pH was significantly higher after the alkalization therapy (6.85±0.74 vs. 6.39±0.92; p0.05). The median overall survival from the start of alkalization therapy of the patients with high urine pH (7.0) was significantly longer than those with low urine pH (≤ 7.0) (16.1 vs. 4.7 months; p0.05).An alkalization therapy may be associated with better outcomes in advanced pancreatic cancer patients treated with chemotherapy.

Background/Aim: Neutralization of the acidic tumor microenvironment, which is associated with both progression and drug resistance of cancer cells, may be a new treatment option for progressing forms of cancer. We conducted a case-control study to investigate the effects of alkalization therapy, consisting of an alkaline diet with supplementary oral sodium bicarbonate, in patients with metastatic or recurrent pancreatic cancer (study registration no.: UMIN000036126). Patients and Methods: Thirty-six patients in the alkalization group (Karasuma Wada Clinic; alkalization therapy plus chemotherapy) were retrospectively compared to 89 patients in the control group (Kyoto University Hospital; chemotherapy only). Results: The median overall survival (OS) in the alkalization group was significantly longer than that in the control group (15.4 vs. 10.8 months; p7.0 or ΔpH>1.0) in the alkalization group was significantly longer than that of the control group. Conclusion: Alkalization therapy may enhance the effects of chemotherapy in patients with advanced pancreatic cancer.

Metabolic acidosis is a severe complication of chronic kidney disease (CKD) which is associated with nefarious impairments such as bone demineralization, muscle wasting, and hormonal alterations, for example, insulin resistance. Whilst it is possible to control this condition with alkali treatment, consisting in the oral administration of sodium citrate or sodium bicarbonate, this type of intervention is not free from side effects. On the contrary, opting for the implementation of a targeted dietetic-nutritional treatment for the control of CKD metabolic acidosis also comes with a range of additional benefits such as lipid profile control, increased vitamins, and antioxidants intake. In our review, we evaluated the main dietary-nutritional regimens useful to counteract metabolic acidosis, such as the Mediterranean diet, the alkaline diet, the low-protein diet, and the vegan low-protein diet, analyzing the potentialities and limits of every dietary-nutritional treatment. Literature data suggest that the Mediterranean and alkaline diets represent a valid nutritional approach in the prevention and correction of metabolic acidosis in CKD early stages, while the low-protein diet and the vegan low-protein diet are more effective in CKD advanced stages. In conclusion, we propose that tailored nutritional approaches should represent a valid therapeutic alternative to counteract metabolic acidosis.

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: &gt, 7.0 mg/dL and &gt, 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 &lt, 0.0001) and 17% (HR: 1.17, 95% CI: 1.04–1.31, p for trend &lt, 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.

It has been proposed that a low-protein diet will slow progression of chronic kidney disease although studies have not always supported this belief. The accepted practice is that 60% to 70% of protein comes from high biological value (HBV) protein, but this limits patient choice and patients struggle to follow the diet. When a diet with only 30% HBV protein was trialed, there was a significant increase in serum bicarbonate, and patients preferred the diet. The dietary advice given in predialysis clinics was changed. HBV protein was restricted to approximately 50% of total protein, bread and cereal foods were allowed freely, and fruits and vegetables (F&V) were encouraged. Patients who followed the diet have seen a slowing of progression and occasionally regression of their renal function. Both observations and scientific literature indicate that this is because of a reduction in the acid content of the diet. When foods are metabolized, most proteins produce acid, and most F&V produce alkali. A typical 21st-century diet produces 50 to 100 mEq H+ per day which the kidney is challenged to excrete. Acid is excreted with phosphate and is limited to about 45 mEq H+ per day. With chronic kidney disease, this falls progressively to below 20 mEq H+ per day. Historically, ammonium excretion was believed to be excretion of acid (NH3+ + H+ → NH4+), but it is now understood to be a by-product in the neutralization of acid by glutamine. The remaining acid is neutralized or stored within the body. Bone and muscle are lost in order to neutralize the acid. Acid also accumulates within cells, and serum bicarbonate falls. The author postulates that reducing the acid load through a low-protein diet with greater use of vegetable proteins and increased F&V intake will slow progression or occasionally improve renal function while maintaining the nutritional status of the individual.

WOS:000537102600002 Study Objectives: The aim of this study was to investigate the effect of an alkaline diet with step aerobic exercises for 8-week in sedentary women on their body composition and aerobic exercise performances. Methods: 22 sedentary women (age = 49.18 +/- 6.28) voluntarily participated in the study (n = 11 alkaline diet group; n = 11 acidic diet group). Alkaline diet and acidic diet programs were applied to the sedentary women together with step aerobic exercises for 8 weeks. This research was designed as a randomized controlled trial model. Body composition (total body weight, fat mass, and free-fat mass), aerobic exercise performance indicators (Bruce treadmill test, lactate accumulation, estimated VO2Max, and rating of perceived exertion) were measured before and after diet and exercise programs. Results: The results of the body weight, fat mass, lactate accumulation, and rating of perceived exertion levels of the group consuming an alkaline diet together with the eight-week step aerobic exercises showed a higher decrease and aerobic exercise performance duration and VO2Max levels indicated a higher increase than acidic diet group. Conclusion: The alkaline diet with reduced acid value together with 8-week step aerobic exercises in sedentary women, has a high rate of positive effects on body composition and aerobic exercise performances.

Potassium bicarbonate was administrated to an already alkaline diet in seven male subjects during a 21-day bed rest study and was able to decrease bed rest induced increased calcium excretion but failed to prevent bed rest-induced bone resorption. Supplementation with alkali salts appears to positively influence calcium and bone metabolism and, thus, could be a countermeasure for population groups with an increased risk for bone loss. However, the extent to which alkalization counteracts acid-induced bone resorption or whether it merely has a calcium and bone maintenance effect is still not completely understood. In the present study, we hypothesized that additional alkalization to an already alkaline diet can further counteract bed rest-induced bone loss. Seven healthy male subjects completed two parts of a crossover designed 21-day bed rest study: bed rest only (control) and bed rest supplemented with 90 mmol potassium bicarbonate (KHCO3) daily. KHCO3supplementation during bed rest resulted in a more alkaline status compared to the control intervention, demonstrated by the increase in pH and buffer capacity level (pH p = 0.023, HCO3p = 0.02, ABE p = 0.03). Urinary calcium excretion was decreased during KHCO3 supplementation (control 6.05 ± 2.74 mmol/24 h; KHCO3 4.87 ± 2.21 mmol/24 h, p = 0.03); whereas, bone formation was not affected by additional alkalization (bAP p = 0.58; PINP p = 0.60). Bone resorption marker UCTX tended to be lower during alkaline supplementation (UCTX p = 0.16). The more alkaline acid-base status, achieved by KHCO3 supplementation, reduced renal calcium excretion during bed rest, but was not able to prevent immobilization-induced bone resorption. However, advantages of alkaline salts on bone metabolism may occur under acidic metabolic conditions or with respect to the positive effect of reduced calcium excretion within a longer time frame. Trial number: NCT01509456

Dietary acid load, quantified as the potential renal acid load (PRAL) of the diet, affects systemic pH and acid-base regulation. In a previous cross-sectional study, we reported that a low dietary PRAL (i.e. alkaline promoting diet) is associated with higher respiratory exchange ratio (RER) values during maximal exercise. The purpose of the present study was to confirm the previous findings with a short-term dietary intervention study. Additionally, we sought to determine if changes in PRAL affects submaximal exercise RER (as a reflection of substrate utilization) and anaerobic exercise performance. Subjects underwent a graded treadmill exercise test (GXT) to exhaustion and an anaerobic exercise performance test on two occasions, once after following a low-PRAL diet and on a separate occasion, after a high-PRAL diet. The diets were continued as long as needed to achieve an alkaline or acid fasted morning urine pH, respectively, with all being 4-9 days in duration. RER was measured during the GXT with indirect calorimetry. The anaerobic performance test was a running time-to-exhaustion test lasting 1-4 min. Maximal exercise RER was lower in the low-PRAL trial compared to the high-PRAL trial (1.10 ± 0.02 vs. 1.20 ± 0.05, p = 0.037). The low-PRAL diet also resulted in a 21% greater time to exhaustion during anaerobic exercise (2.56 ± 0.36 vs. 2.11 ± 0.31 sec, p = 0.044) and a strong tendency for lower RER values during submaximal exercise at 70% VO2max (0.88 ± 0.02 vs. 0.96 ± 0.04, p = 0.060). Contrary to our expectations, a short-term low-PRAL (alkaline promoting) diet resulted in lower RER values during maximal-intensity exercise. However, the low-PRAL diet also increased anaerobic exercise time to exhaustion and appears to have shifted submaximal exercise substrate utilization to favor lipid oxidation and spare carbohydrate, both of which would be considered favorable effects in the context of exercise performance.

Background: High dietary acid load relates to increased risk of type 2 diabetes in epidemiological studies. We aimed to investigate whether buffering a high acid load meal with an alkalising treatment changes post meal glucose metabolism. Methods: Non-diabetic participants (n=32) were randomized to receive either NaHCO3 1680mg or placebo, followed by a high acid load meal in a double-blind placebo-controlled crossover (1-4 weeks apart) study. Thirty (20 males) participants completed the study. Venous blood pH, serum bicarbonate, blood glucose, serum insulin, C-peptide, non-esterified fatty acid (NEFA), and plasma glucagon-like peptide-1 (GLP-1) concentrations were measured at baseline (fasting) and at 15-30min intervals for 3h post meal. Results: The treatment was well tolerated. Venous blood pH declined in the first 15min post meal with the placebo (p=0.001), but not with NaHCO3 (p=0.86) and remained lower with the placebo for 3h (pinteraction=0.04). The iAUC of pH was significantly higher following the NaHCO3 treatment versus the placebo (p=0.02). However, postprandial glucose, insulin, C-peptide, NEFA and GLP-1 were not different between treatments (pinteraction≥0.07). Conclusions: An alkalising medication administered pre-meal has no acute effect on glycaemia and insulin response in healthy individuals. Long-term interventions in at-risk populations are necessary to investigate the effect of sustained alkalisation on glucose metabolism.

The kidneys play an extremely important role in maintaining the body acid–base balance by excreting nonvolatile acids and regenerating and reabsorbing bicarbonate in the kidney tubules. As the individual loses their kidney function, renal excretion of nonvolatile acid produced by metabolism of the diet is impaired, resulting in low-grade metabolic acidosis. With this in mind, it is relevant to better understand the dietary aspects related to the acid–base balance in chronic kidney disease metabolic acidosis and try to provide possible strategies for the nutritional management of these cases. The type of diet can deeply affect the body by providing acid or base precursors. Generally speaking, foods such as meat, eggs, cheese, and grains increase the production of acid in the organism, whereas fruit and vegetables are alkalizing. On the other hand, milk is considered neutral as well as fats and sugars, which have a small effect on acid–base balance. The modern Western-type diet is deficient in fruits and vegetables and contains excessive animal products. Thus metabolic acidosis may be exacerbated by a contemporary Western diet, which delivers a high nonvolatile acid load. The remaining acid is neutralized or stored within the body. Bone and muscle are lost to neutralize the acid and serum bicarbonate falls. Early studies suggest that lowering the dietary acid load with a reduced protein content and vegetable proteins replacements, associated with an increase in fruits and vegetables intake can improve the metabolic parameters of acidosis, preserve bone and muscle, and slow the glomerular filtration rate decline. More studies focusing on the effects of controlled dietary interventions among chronic kidney disease patients are needed to determining the optimal target for nutritional therapy.

Background The acidic tumor microenvironment is associated with progression of cancers. The purpose of this study was to investigate the association between an alkaline diet and the effect of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) in non-small cell lung cancer (NSCLC) patients. Patients and methods Eleven advanced or recurrent NSCLC patients with EGFR mutations treated with EGFR-TKI after being instructed to follow an alkaline diet were retrospectively evaluated. Results The median progression-free survival (PFS) and overall survival (OS) were 19.5 (range=3.1-33.8) and 28.5 (range=15.4-46.6) months. The average dosage of EGFR-TKI was 56±22% of the standard dosage. Urine pH was significantly increased after the alkaline diet (6.00±0.38 vs. 6.95±0.55; p Conclusion An alkaline diet may enhance the effect of EGFR-TKI treatment in NSCLC patients with EGFR mutations.

Diet-related mild metabolic acidosis may play a role in the development of sarcopenia. We investigated the relationship between dietary acid load and total lean body mass in male and female seniors age ≥ 60 years. We found that a more alkaline diet was associated with a higher %TLM only among senior women. The aim of this study was to determine if dietary acid load is associated with total lean body mass in male and female seniors age ≥ 60 years. We investigated 243 seniors (mean age 70.3 ± 6.3; 53% women) age ≥ 60 years who participated in the baseline assessment of a clinical trial on vitamin D treatment and rehabilitation after unilateral knee replacement due to severe knee osteoarthritis. The potential renal acid load (PRAL) was assessed based on individual nutrient intakes derived from a food frequency questionnaire. Body composition including percentage of total lean body mass (%TLM) was determined using dual-energy X-ray absorptiometry. Cross-sectional analyses were performed for men and women separately using multivariable regression models controlling for age, physical activity, smoking status, protein intake (g/kg BW per day), energy intake (kcal), and serum 25-hydroxyvitamin D concentration. We included a pre-defined subgroup analysis by protein intake ( 1 g/kg BW day) and by age group (

A popular concept in nutrition and lay literature is that of the role of a diet high in acid or protein in the pathogenesis of osteoporosis. A diet rich in fruit and vegetable intake is thought to enhance bone health as the result of its greater potassium and lower "acidic" content than a diet rich in animal protein and sodium. Consequently, there have been a number of studies of diet manipulation to enhance potassium and "alkaline" content of the diet to improve bone density or other parameters of bone health. Although acid loading or an acidic diet featuring a high protein intake may be associated with an increase in calciuria, the evidence supporting a role of these variables in the development of osteoporosis is not consistent. Similarly, intervention studies with a more alkaline diet or use of supplements of potassium citrate or bicarbonate have not consistently shown a bone health benefit. In the elderly, inadequate protein intake is a greater problem for bone health than protein excess.

Dietary ion content is known to alter the acid-base balance in freshwater fish. The current study investigated the metabolic impact of acid-base disturbances produced by differences in dietary electrolyte balance (DEB) in the meagre (Argyrosomus regius), an euryhaline species. Changes in fish performance, gastric chyme characteristics, pH and ion concentrations in the bloodstream, digestive enzyme activities and metabolic rates were analyzed in meagre fed ad libitum two experimental diets (DEB 200 or DEB 700 mEq/kg) differing in the Na2CO3 content for 69 days. Fish fed the DEB 200 diet had 60–66% better growth performance than the DEB 700 group. Meagre consuming the DEB 200 diet were 90–96% more efficient than fish fed the DEB 700 diet at allocating energy from feed into somatic growth. The pH values in blood were significantly lower in the DEB 700 group 2 h after feeding when compared to DEB 200, indicating that acid-base balance in meagre was affected by electrolyte balance in diet. Osmolality, and Na+ and K+ concentrations in plasma did not vary with the dietary treatment. Gastric chyme in the DEB 700 group had higher pH values, dry matter, protein and energy contents, but lower lipid content than in the DEB 200 group. Twenty-four hours after feeding, amylase activity was higher in the gastrointestinal tract of DEB 700 group when compared to the DEB 200 group. DEB 700 group had lower routine metabolic (RMR) and standard metabolic (SMR) rates, indicating a decrease in maintenance energy expenditure 48 h after feeding the alkaline diet. The current study demonstrates that feeding meagre with an alkaline diet not only causes acid-base imbalance, but also negatively affects digestion and possibly nutrient assimilation, resulting in decreased growth performance. Fil: Magnoni, Leonardo Julián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); Argentina. Terminal de Cruzeiros do Porto de Leixões; Brasil Fil: Salas Leiton, Emilio. Terminal de Cruzeiros do Porto de Leixões; Brasil. IFAPA; España Fil: Peixoto, Maria João. Terminal de Cruzeiros do Porto de Leixões; Brasil. Universidad de Porto; Portugal Fil: Pereira, Luis. Terminal de Cruzeiros do Porto de Leixões; Brasil Fil: Silva Brito, Francisca. Terminal de Cruzeiros do Porto de Leixões; Brasil Fil: Fontinha, Filipa. Terminal de Cruzeiros do Porto de Leixões; Brasil Fil: Gonçalves, José F.M.. Terminal de Cruzeiros do Porto de Leixões; Brasil. Universidad de Porto; Portugal Fil: Wilson, Jonathan M.. Terminal de Cruzeiros do Porto de Leixões; Brasil. Universidad de Porto; Portugal. Wilfrid Laurier University; Canadá Fil: Schrama, Johan W.. University of Agriculture Wageningen; Países Bajos Fil: Ozório, Rodrigo O.A.. Terminal de Cruzeiros do Porto de Leixões; Brasil. Universidad de Porto; Portugal

We read with great interest the recently published article in Physiological Reports on protein intake, renal acid load, and hemodynamic responses (Teunissen‐Beekman et al. 2016). In their study, Teunissen‐Beekman et al. examined effects of an increase in protein intake (60 g/day, given as a mix of protein isolates, 20% pea, 20% soy, 30% egg‐white, 30% milk) on glomerular filtration rate (GFR) and related renally relevant parameters in overweight individuals with untreated elevated blood pressure and normal kidney function. Contrary to the author's initial hypothesis, neither fasting nor postprandial GFR values (the latter adjusted for the fasting measurements) were higher in the protein‐supplemented group (PROT) compared with a second group (MALT) which instead received 60 g/day of maltodextrin on an isoenergetic basis. The authors reported overall remarkably high GFR values in their subjects along with a short temporary GFR decline within 30 min postprandially in the protein‐supplemented group that was not seen in MALT. As expected, the authors found a significantly higher renal acid load after 4 weeks on the protein supplement compared to 4 weeks on maltodextrin. 24‐h renal acid load was determined as urinary PRAL (uPRAL), a biomarker that characterizes the mineral component (including sulfate from sulfur‐containing amino acids) of total renal net acid excretion (NAE) without considering the organic acid component (Krupp et al. 2014). Unexpectedly, the observed uPRAL difference after 4 weeks on higher protein ingestion versus baseline was only about 15 mEq/day. This is half of what is known from the literature for protein increases of that magnitude (Remer and Manz 1994, 1995a). In accord herewith, in a separate article on the present diet experiment (Teunissen‐Beekman et al. 2012), the authors reported differences in urinary sulfate excretion after 4 weeks (for PROT vs. MALT, and for PROT vs. baseline) of 7–8 mmol/day corresponding to 15 mEq of renally excreted dietary acidity stemming from sulfur amino acid metabolism. However, 30 mEq/day of “sulfate acidity” would have been expected with an increase of 60 g/day of a protein mix of that composition (Remer and Manz 1995b). It appears worth considering, whether a lower compliance at the end of the 4 week observation period might have contributed to the too low acid excretion after protein supplementation of that magnitude. Interestingly, also the average renal acid load component (4) measured as uPRAL in 24‐h urine samples of both groups (PROT and MALT) has been found to be remarkably low, both at baseline and after 4 weeks of diet intervention. Mean uPRAL varied between ca. −5 mEq and ca. −20 mEq/day (Figure 4; Teunissen‐Beekman et al. 2016) confirming a largely alkalizing basic nutrition present already at run‐in. In contrast, healthy adults of the DONALD study with an average protein intake of 115 g/day – that is, almost comparable to PROT – show mean uPRAL values around +50 mEq/day corresponding to a NAE of ca. 90 mEq/day and reflecting a rather higher dietary acid load. The fact that the authors, notwithstanding, found a low uPRAL range throughout (

Conservation of muscle mass is important for fall and fracture prevention but further understanding of the causes of age-related muscle loss is required. This study found a more alkaline diet was positively associated with muscle mass in women suggesting a role for dietary acid–base load in muscle loss. Conservation of skeletal muscle is important for preventing falls and fractures but age-related loss of muscle mass occurs even in healthy individuals. However, the mild metabolic acidosis associated with an acidogenic dietary acid–base load could influence loss of muscle mass. We investigated the association between fat-free mass (FFM), percentage FFM (FFM%) and fat-free mass index (FFMI, weight/height2), measured using dual-energy X-ray absorptiometry in 2,689 women aged 18–79 years from the TwinsUK Study, and dietary acid–base load. Body composition was calculated according to quartile of potential renal acid load and adjusted for age, physical activity, misreporting and smoking habit (FFM, FFMI also for fat mass) and additionally with percentage protein. Fat-free mass was positively associated with a more alkalinogenic dietary load (comparing quartile 1 vs 4: FFM 0.79 kg P

The acid-ash hypothesis posits that protein and grain foods, with a low potassium intake, produce a diet acid load, net acid excretion (NAE), increased urine calcium, and release of calcium from the skeleton, leading to osteoporosis. The objectives of this meta-analysis were to assess the effect of changes in NAE, by manipulation of healthy adult subjects' acid-base intakes, on urine calcium, calcium balance, and a marker of bone metabolism, N-telopeptides. This meta-analysis was limited to studies that used superior methodological quality for the study of calcium metabolism. We systematically searched the literature and included studies if subjects were randomized to the interventions and followed the recommendations of the Institute of Medicine's Panel on Calcium and Related Nutrients for calcium studies. Five of 16 studies met the inclusion criteria. The studies altered the amount and/or type of protein. Despite a significant linear relationship between an increase in NAE and urinary calcium (p < 0.0001), there was no relationship between a change of NAE and a change of calcium balance (p = 0.38; power = 94%). There was no relationship between a change of NAE and a change in the marker of bone metabolism, N-telopeptides (p = 0.95). In conclusion, this meta-analysis does not support the concept that the calciuria associated with higher NAE reflects a net loss of whole body calcium. There is no evidence from superior quality balance studies that increasing the diet acid load promotes skeletal bone mineral loss or osteoporosis. Changes of urine calcium do not accurately represent calcium balance. Promotion of the "alkaline diet" to prevent calcium loss is not justified.

Type 2 diabetes is increasingly being recognised as a global health crisis (World Health Organisation). Insulin resistance is closely associated with obesity and precedes the development of type 2 diabetes. However, there is now increasing evidence to suggest that diet itself may independently be associated with type 2 diabetes risk. A diet with a high acid load (or high potential renal net acid load, PRAL) can result in a decrease in pH towards the lower end of the normal physiological range, which may in turn lead to the development of insulin resistance. Conversely, reducing dietary acid load (the so called ‘alkaline diet’) may be protective and prevent the onset of type 2 diabetes. Here, we explore the influence of dietary acid load on the development of mild metabolic acidosis and induction of insulin resistance. Whilst large prospective cohort studies link high dietary acid load or low serum bicarbonate with the development of type 2 diabetes, the effect of a diet with a low acid (or high alkaline) load remains unclear. Further interventional studies are required to investigate the influence of dietary composition on the body's acid/base balance, insulin resistance and incidence of type 2 diabetes.

Background: High dietary acid load relates to increased risk of type 2 diabetes in epidemiological studies. We aimed to investigate whether buffering a high acid load meal with an alkalizing treatment changes glucose metabolism post meal. Methods: Non-diabetic participants (n = 32) were randomized to receive either 1680 mg NaHCO3 or placebo, followed by a high acid load meal in a double-blind placebo-controlled crossover (1–4 weeks apart) study. Thirty (20 men) participants completed the study. Venous blood pH, serum bicarbonate, blood glucose, serum insulin, C-peptide, non-esterified fatty acid (NEFA), and plasma glucagon-like peptide-1 (GLP-1) concentrations were measured at baseline (fasting) and at 15–30 min intervals for 3 h post meal. Results: The treatment was well tolerated. Venous blood pH declined in the first 15 min post meal with the placebo (p = 0.001), but not with NaHCO3 (p = 0.86) and remained decreased with the placebo for 3 h (pinteraction = 0.04). On average over the 3 h blood pH iAUC was greater with NaHCO3 compared with placebo (p = 0.02). However, postprandial glucose, insulin, C-peptide, NEFA and GLP-1 were not different between treatments (pinteraction ≥ 0.07). Conclusions: An alkalizing medication administered pre-meal has no acute effect on glycaemia and insulin response in healthy individuals. Long-term interventions in at-risk populations are necessary to investigate the effect of sustained alkalization on glucose metabolism.

Background: Osteoarthritis (OA) is a chronic condition. Nonsteroidal anti-inflammatory drugs recommended for treatment have serious adverse effects. A compelling body of anecdotal evidence alerted the authors to the therapeutic potential of dietary supplementation with Multiforce® (MF) Alkaline Powder for relief of OA symptoms. Aim: The aim of the study was to test the hypothesis that dietary supplementation with MF relieves clinical signs and symptoms of OA of the hands. Setting: The study was done at the MEDSAC hospital in Somerset West, Western Cape, South Africa. Methods: The research was conducted in two stages. An open interventional study (n = 40) confirmed the notion that MF 7.5 g twice daily is likely to be an effective alternative or adjunct for relief of symptoms of OA of the hands. The main study was conducted with 100 eligible, consenting volunteers (aged 47–89 years) according to a randomised, placebo-controlled, crossover design. Study duration was 56 days, 28 days per regimen; crossover to alternate regimens took place on day 28. Results: Compared to placebo, MF intake over 28 days was associated with significant reductions ( p < 0.005) in pain, tenderness and stiffness of interphalangeal and metacarpophalangeal joints of the hand. Confirmation of systemic alkalinisation by MF, which is rich in organic anions in the form of citrate salts, was reflected by a significant and sustained increase in urine pH. Conclusion: A dietary supplement, Multiforce® Alkaline Powder, containing citrate salts which are converted into bicarbonate in vivo, was efficacious and safe as sole therapeutic intervention, significantly attenuating OA-associated signs and symptoms of the hands.

The urine-acidifying properties of food constituents depend on their content of non-oxidizable acids or precursors. Acidifying constituents such as animal proteins may negatively affect calcium metabolism and accelerate bone resorption, thus representing an aggravating factor for osteoporosis. This four-period, double-crossover study investigated whether a diet intervention specifically focused on acid load could modify calcium metabolism in humans. Eight healthy volunteers underwent a four-day metabolic preparation with two types of diets, one rich in acid ash-forming nutrients, and one providing base-forming nutrients (including bicarbonate-rich mineral water), both having similar contents of calcium, phosphate, sodium, proteins and calories. On the fourth day, a single oral dose of 1 g calcium was given, either as carbonate or as gluconolactate. Serial blood and urine samples revealed that the diet affected blood pH (average difference 0.014, p = 0.002) and urine pH (average difference 1.02, p

The purpose of this study was to calculate the potential renal acid load (PRAL) of selected, frequently consumed foods. A physiologically based calculation model was recently validated to yield an appropriate estimate of renal net acid excretion (NAE); the model depends primarily on nutrient intake data. When nutrient data from actual food composition tables were used, the calculation model yielded PRAL values that ranged from an average maximum of 23.6 mEq/100 g for certain hard cheeses over 0 mEq/100 g for fats and oils to an average minimum of approximately -3 mEq/100 g for fruits and fruit juices and vegetables. By means of these PRAL data (summed according to the amounts of foods and beverages consumed daily and by an estimate of excretion of organic acids [based on body size]), the daily NAE can be calculated. This calculation methodology, primarily based on PRAL, allows an appropriate prediction of the effects of diet on the acidity of urine. For practical applicability in dietetic prevention of recurrent urolithiasis or in other fields of dietetics, the additionally determined correlation (r = .83; P.001) between NAE and urine pH can be used to ascertain NAE target values for a desired urine pH modification.

Objectives To evaluate the evidence for a causal relationship between dietary acid/alkaline and alkaline water for the aetiology and treatment of cancer. Design A systematic review was conducted on published and grey literature separately for randomised intervention and observational studies with either varying acid–base dietary intakes and/or alkaline water with any cancer outcome or for cancer treatment. Outcome measures Incidence of cancer and outcomes of cancer treatment. Results 8278 citations were identified, and 252 abstracts were reviewed; 1 study met the inclusion criteria and was included in this systematic review. No randomised trials were located. No studies were located that examined dietary acid or alkaline or alkaline water for cancer treatment. The included study was a cohort study with a low risk of bias. This study revealed no association between the diet acid load with bladder cancer (OR=1.15: 95% CI 0.86 to 1.55, p=0.36). No association was found even among long-term smokers (OR=1.72: 95% CI 0.96 to 3.10, p=0.08). Conclusions Despite the promotion of the alkaline diet and alkaline water by the media and salespeople, there is almost no actual research to either support or disprove these ideas. This systematic review of the literature revealed a lack of evidence for or against diet acid load and/or alkaline water for the initiation or treatment of cancer. Promotion of alkaline diet and alkaline water to the public for cancer prevention or treatment is not justified.

This review looks at the role of an alkaline diet in health. Pubmed was searched looking for articles on pH, potential renal acid loads, bone health, muscle, growth hormone, back pain, vitamin D and chemotherapy. Many books written in the lay literature on the alkaline diet were also reviewed and evaluated in light of the published medical literature. There may be some value in considering an alkaline diet in reducing morbidity and mortality from chronic diseases and further studies are warranted in this area of medicine.

In normal subjects, a low level of metabolic acidosis and positive acid balance (the production of more acid than is excreted) are typically present and correlate in degree with the amount of endogenous acid produced by the metabolism of foods in ordinary diets abundant in protein. Over a lifetime, the counteraction of retained endogenous acid by base mobilized from the skeleton may contribute to the decrease in bone mass that occurs normally with aging.To test that possibility, we administered potassium bicarbonate to 18 postmenopausal women who were given a constant diet (652 mg [16 mmol] of calcium and 96 g of protein per 60 kg of body weight). The potassium bicarbonate was given orally for 18 days in doses (60 to 120 mmol per day) that nearly completely neutralized the endogenous acid.During the administration of potassium bicarbonate, the calcium and phosphorus balance became less negative or more positive--that is, less was excreted in comparison with the amount ingested (mean [+/- SD] change in calcium balance, +56 +/- 76 mg [1.4 +/- 1.9 mmol] per day per 60 kg; P = 0.009; change in phosphorus balance, +47 +/- 64 mg [1.5 +/- 2.1 mmol] per day per 60 kg; P = 0.007) because of reductions in urinary calcium and phosphorus excretion. The changes in calcium and phosphorus balance were positively correlated (P0.001). Serum osteocalcin concentrations increased from 5.5 +/- 2.8 to 6.1 +/- 2.8 ng per milliliter (P0.001), and urinary hydroxyproline excretion decreased from 28.9 +/- 12.3 to 26.7 +/- 10.8 mg per day (220 +/- 94 to 204 +/- 82 mumol per day; P = 0.05). Net renal acid excretion decreased from 70.9 +/- 10.1 to 12.8 +/- 21.8 mmol per day, indicating nearly complete neutralization of endogenous acid.In postmenopausal women, the oral administration of potassium bicarbonate at a dose sufficient to neutralize endogenous acid improves calcium and phosphorus balance, reduces bone resorption, and increases the rate of bone formation.