Effects of mineral waters on acid-base status in healthy adults: results of a randomized trial

Blood Pressure Stability and Plasma Aldosterone Reduction: The Effects of a Sodium and Bicarbonate-Rich Water - A Randomized Controlled Intervention Study

Objective: Hypertension is a recognized risk factor for cardiovascular disease (CVD), and dietary sodium intake has been linked to its development. However, mineral water high in bicarbonate and sodium does not appear to have adverse effects on blood pressure.This study examines the effects of consuming a mineral water high in bicarbonate and sodium (HBS) compared to a low bicarbonate and sodium (LBS) mineral water on blood pressure and related factors.Methods: A randomized controlled intervention was conducted with 94 healthy participants, consuming 1,500 - 2,000 mL daily of either mineral water high in bicarbonate and sodium (HBS water, n = 49) or low in bicarbonate and sodium (LBS water, n = 45). Blood pressure, anthropometrics, and urinary calcium and sodium excretion were assessed at baseline and after 28 days. 3-day food protocols were assessed to evaluate possible dietary changes.Results: Blood pressure changes did not differ between the groups. Both normotensive and hypertensive subjects showed similar changes in systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) in response to the different test waters. Serum aldosterone decreased significantly in both groups, with a greater reduction in the HBS group. Urinary calcium excretion significantly decreased (p = 0.002) and sodium excretion increased in the HBS group. Multiple linear regression analyses indicated no association between urinary sodium excretion and systolic blood pressure increase in the HBS group (B = 0.046, p = 0.170). Changes in urinary sodium excretion did not correlate with changes in serum aldosterone in the same group (r=-0.146, p = 0.350).Conclusions: The study revealed no significant differences in blood pressure changes between individuals consuming HBS water and LBS water. Notably, the additional sodium intake from the test water was effectively excreted.Trial registration: This trial was registered in the German Clinical Trials Register (DRKS00025341, https://drks.de/search/en).

The Multidisciplinary Approach in the Management of Patients with Kidney Stone Disease-A State-of-the-Art Review

Kidney stone disease has a multifactorial etiology, and evolving dietary habits necessitate continuous updates on the impact of dietary components on lithogenesis. The relationship between diseases influenced by lifestyle, such as obesity and diabetes, and kidney stone risk underscores the need for comprehensive lifestyle analysis. Effective management of kidney stones requires a multidisciplinary approach, involving collaboration among nutritionists, urologists, nephrologists, and other healthcare professionals to address the complex interactions between diet, lifestyle, and individual susceptibility. Personalized dietary therapy, based on each patient's unique biochemical and dietary profile, is essential and necessitates comprehensive nutritional assessments. Accurate dietary intake evaluation is best achieved through seven-day, real-time dietary records. Key factors influencing urinary risk include fluid intake, dietary protein, carbohydrates, oxalate, calcium, and sodium chloride. Personalized interventions, such as customized dietary changes based on gut microbiota, may improve stone prevention and recurrence. Current research suggests individualized guidance on alcohol intake and indicates that tea and coffee consumption might protect against urolithiasis. There is potential evidence linking tobacco use and secondhand smoke to increased kidney stone risk. The effects of vitamins and physical activity on kidney stone risk remain unresolved due to mixed evidence. For diseases influenced by lifestyle, conclusive evidence on targeted interventions for nephrolithiasis prevention is lacking, though preliminary research suggests potential benefits. Management strategies emphasize lifestyle modifications to reduce recurrence risks, support rapid recovery, and identify predisposing conditions, highlighting the importance of these changes despite inconclusive data.

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.

Diet and Metabolism in CKD-Related Metabolic Acidosis

Metabolic acidosis is a common complication in patients with chronic kidney disease that occurs when the daily nonvolatile acid load produced in metabolism cannot be excreted fully by the kidney. A reduction in urine net acid excretion coupled with a high nonvolatile acid load may play a role in its pathogenesis. Diet is important in generation of the nonvolatile acid load. Acids are produced from metabolism of dietary protein and from the endogenous production of organic anions from neutral precursors. Acids can be balanced by alkali precursors ingested in the diet in the form of combustible organic anions. These typically are reflected indirectly by the excess of mineral cations to mineral anions in a food or diet. These principles underscore widely used methods to estimate the nonvolatile acid load from dietary intake using formulas such as the net endogenous acid production equation and the potential renal acid load equation. Empiric data largely validate these paradigms with high net endogenous acid production and potential renal acid load contributed by foods such as protein, grains, and dairy, and low net endogenous acid production and potential renal acid load contributed by fruits and vegetables along with corresponding dietary patterns. Although further studies are needed to understand the health benefits of altering nonvolatile acid load via diet, this review provides a detailed assessment on our current understanding of the role of diet in chronic kidney disease-related acidosis, providing an updated resource for researchers and clinicians.

Fluid intake recommendations in urolithiasis and general advice to patients without metabolic risk factors

Urolithiasis is a highly prevalent global disease with substantially increasing incidence in the last two decades. Data from the literature suggests that 26%-50% of patients will have a recurrence within 10 years after an initial symptomatic stone episode. Therefore, interest has been raised in preventive strategies, aiming to modify the risk factors of stone recurrence by implementing dietary and lifestyle changes and specific medical treatments for stone formers, depending on their recurrence risk factors. Certain dietary factors are thought to contribute significantly to the increased incidence of urolithiasis, particularly a diet low in fiber and high in animal protein, fat, and sodium. Fluid intake is perhaps the most important and modifiable step in the prevention of urolithiasis, irrespective of stone composition. However, the amount of fluid to be consumed and the implications of various fluid types on stone formation are still controversial. In this article, the relationship between fluid intake, beverage types and stone formation-prevention will be discussed. Moreover, general dietary recommendations for patients without metabolic risk factors will be reviewed based on the current literature.

Assessment of the Erosive Potential of Mineral Waters in Bovine Dental Enamel

Background:

High intake of acidic foods and beverages has been often associated with the onset of dental erosive wear.

Objetive:

This study in vitro assessed the pH of different mineral waters marketed in Brazil and their effects on the properties and surface of dental enamel.

Methods:

Forty-eight bovine incisor specimens were divided into four groups (n=12): CG-control group, PeG-Perrier, PrG-Prata, and SLG-São Lourenço. The immersion cycles were performed after analysis of the pH of the waters, for 5 days (5 minutes in mineral water and 60 minutes in artificial saliva). Knoop micro-hardness was assessed by means of three indentations with a load of 50kgf for 15 seconds, and surface roughness with a cut off of 0.25mm. The data were analysed using Student's t-test, ANOVA, and Tukey test, with a significance level of 5%.

Results:

The groups of waters with lower pH (Perrier® and São Lourenço®) exhibited a reduction in Knoop micro-hardness (p<0.0001) and an increase in surface roughness (p=0.04 and p=0.004, respectively). The Prata water group did not exhibit significant changes in Knoop micro-hardness (p=0.07) and surface roughness (p=0.26).

Conclusion:

Mineral waters with a pH below the critical value can lead to a reduction in surface hardness and roughness in the bovine enamel.

Drinking Natural Mineral Water Maintains Bone Health in Young Rats With Metabolic Acidosis

Introduction

Metabolic acidosis affects bone health. It remains unclear whether drinking natural mineral water is better for maintaining bone health in the youth with metabolic acidosis.

Materials and Methods

Sixty young female rats (3-weeks-old) were randomly divided into three groups and drank purified water (PW, as control), bicarbonate-rich natural mineral water (Bic-NMW), or sulfate-rich natural mineral water (Sul-NMW), which, respectively, contained calcium (0.17, 155, and 175 mg/L), bicarbonate (0.1360, and 139 mg/L) and sulfate (0, 35.6, and 532 mg/L), for 16 weeks. In the last 3 weeks, metabolic acidosis was induced in 10 rats per group by adding NH₄Cl (0.28 mM) to drinking water. The rats' blood, urine, and femur were collected for assessing acid-base status, calcium metabolism, bone microstructure, and strength. The difference between the three groups was determined using one-way ANOVA followed by the Student–Newman–Keuls test or Dunnett's T3 test.

Results

Compared with the PW rats, the Bic-NMW rats and the Sul-NMW rats had less urine net acid excretion (−1.51, 0.20 vs. 10.77, EQ/L), higher bone mineral density (442.50, 407.49 vs. 373.28, mg/mm³), growth cartilage width (271.83, 283.83 vs. 233.27, μm) and cortical trabecular area (9.33, 9.55 vs. 5.05, mm²), and smaller cortical marrow cavity area (5.40, 5.49 vs. 7.27, mm²) in the femur (P < 0.05). Besides, the Bic-NMW rats had less serum calcium (2.53 vs. 2.68, mmol/L) and C-terminal cross-linked telopeptide of type-I collagen (1.35 vs. 1.93, ng/mL), and higher serum calcitonin (0.61 vs. 0.39, μg/L), femoral trabecular thickness (0.10 vs. 0.09, μm), bone volume/total volume (0.42 vs. 0.34, %), cortical bone area (15.91 vs. 12.80, mm²), and ultimate stress (35.12 vs. 29.32, MPa) (P < 0.05). The Sul-NMW rats had more osteoclasts (22.50 vs. 11.54, cells/field) (P < 0.05).

Conclusions

Drinking natural mineral water, especially bicarbonate-rich natural mineral water, is effective in improving bone health in young rats with metabolic acidosis. These benefits include maintaining bone mineral density, and improving bone microstructure and biomechanical properties via moderating metabolic acidosis.

Hydropinotherapy with Sulphurous Mineral Water as Complementary Treatment to Improve Glucose Metabolism, Oxidative Status, and Quality of Life

Hydropinotherapy is a salus per aquam (Spa) treatment suitable as a complementary approach to treat several diseases, which strongly affect the quality of life (QoL). Hydropinotherapy with sulphurous mineral water exerts benefits thanks to components, such as hydrogen sulphide, which is considered mainly responsible for antioxidant and hypoglycaemic effects. Such properties, linked from each other, could favour an improvement in patients’ QoL. However, data on humans are scarce. This study aimed to investigate whether a cycle of sulphurous hydropinotherapy was able to modify plasma levels of glucose and reactive oxygen metabolites (ROMs) and improve QoL in patients suffering from several chronic disorders. A prospective, observational study involved patients with gastrointestinal diseases who received a prescription of a cycle of sulphurous hydropinotherapy (S-HT). Age- and sex-matched control group was enrolled (No S-HT). Glycaemia and plasma concentration of ROMs were measured in all subjects. The impact of spa treatment on the QoL was assessed using the Short Form 36 Health Status Survey questionnaire (SF-36). All parameters were measured at baseline and at the end of a 2-week treatment. Between the groups, no differences were found in glycaemia and ROMs at baseline. In the S-HT group, a reduction in glycaemia and ROMs, both in respect to baseline (p = 0.005 and p = 0.031, respectively) and to control group, as shown by the delta value calculated, as the difference between the values at 2 weeks and baseline (p = 0.0009 and p = 0.0001, respectively). In the S-HT, delta ROMs was the best predictor of delta glycaemia with a direct linear correlation (beta = 0.559, 95% CI 0.471 to 0.647, p < 0.0001). In the S-HT, the SF-36 total score was improved both when compared with baseline (p = 0.002) and with No S-HT (p = 0.001). Sulphurous hydropinotherapy induces a decrease in glycaemia and ROM levels, also ameliorating the patients’ QoL. Therefore, it could be considered a useful complementary therapeutic approach.

Nutrition and Kidney Stone Disease

The prevalence of kidney stone disease is increasing worldwide. The recurrence rate of urinary stones is estimated to be up to 50%. Nephrolithiasis is associated with increased risk of chronic and end stage kidney disease. Diet composition is considered to play a crucial role in urinary stone formation. There is strong evidence that an inadequate fluid intake is the major dietary risk factor for urolithiasis. While the benefit of high fluid intake has been confirmed, the effect of different beverages, such as tap water, mineral water, fruit juices, soft drinks, tea and coffee, are debated. Other nutritional factors, including dietary protein, carbohydrates, oxalate, calcium and sodium chloride can also modulate the urinary risk profile and contribute to the risk of kidney stone formation. The assessment of nutritional risk factors is an essential component in the specific dietary therapy of kidney stone patients. An appropriate dietary intervention can contribute to the effective prevention of recurrent stones and reduce the burden of invasive surgical procedures for the treatment of urinary stone disease. This narrative review has intended to provide a comprehensive and updated overview on the role of nutrition and diet in kidney stone disease.