Urine pH is an indicator of dietary acid–base load, fruit and vegetables and meat intakes: results from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Norfolk population study

Evidence exists that a more acidic diet is detrimental to bone health. Although more precise methods exist for measurement of acid–base balance, urine pH reflects acid–base balance and is readily measurable but has not been related to habitual dietary intake in general populations. The present study investigated the relationship between urine pH and dietary acid–base load (potential renal acid load; PRAL) and its contributory food groups (fruit and vegetables, meats, cereal and dairy foods). There were 22 034 men and women aged 39–78 years living in Norfolk (UK) with casual urine samples and dietary intakes from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Norfolk FFQ. A sub-study (n 363) compared pH in casual samples and 24 h urine and intakes from a 7 d diary and the FFQ. A more alkaline diet (low PRAL), high fruit and vegetable intake and lower consumption of meat was significantly associated with a more alkaline urine pH before and after adjustment for age, BMI, physical activity and smoking habit and also after excluding for urinary protein, glucose, ketones, diagnosed high blood pressure and diuretic medication. In the sub-study the strongest relationship was found between the 24 h urine and the 7 d diary. In conclusion, a more alkaline diet, higher fruit and vegetable and lower meat intake were related to more alkaline urine with a magnitude similar to intervention studies. As urine pH relates to dietary acid–base load its use to monitor change in consumption of fruit and vegetables, in individuals, warrants further investigation.

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Higher Dietary Acidity is Associated with Lower Bone Mineral Density in Postmenopausal Iranian Women, Independent of Dietary Calcium Intake

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000207 ◽

2014 ◽

Vol 84 (3-4) ◽

pp. 0206-0217 ◽

Cited By ~ 8

Author(s):

Seyedeh-Elaheh Shariati-Bafghi ◽

Elaheh Nosrat-Mirshekarlou ◽

Mohsen Karamati ◽

Bahram Rashidkhani

Keyword(s):

Calcium Intake ◽

Dietary Calcium ◽

Dietary Calcium Intake ◽

Dietary Intakes ◽

Iranian Women ◽

Acid Base Balance ◽

Mineral Density ◽

Acid Base ◽

Base Balance ◽

Dietary Acid

Findings of studies on the link between dietary acid-base balance and bone mass are relatively mixed. We examined the association between dietary acid-base balance and bone mineral density (BMD) in a sample of Iranian women, hypothesizing that a higher dietary acidity would be inversely associated with BMD, even when dietary calcium intake is adequate. In this cross-sectional study, lumbar spine and femoral neck BMDs of 151 postmenopausal women aged 50 - 85 years were measured using dual-energy x-ray absorptiometry. Dietary intakes were assessed using a validated food frequency questionnaire. Renal net acid excretion (RNAE), an estimate of acid-base balance, was then calculated indirectly from the diet using the formulae of Remer (based on dietary intakes of protein, phosphorus, potassium, and magnesium; RNAERemer) and Frassetto (based on dietary intakes of protein and potassium; RNAEFrassetto), and was energy adjusted by the residual method. After adjusting for potential confounders, multivariable adjusted means of the lumbar spine BMD of women in the highest tertiles of RNAERemer and RNAEFrassetto were significantly lower than those in the lowest tertiles (for RNAERemer: mean difference -0.084 g/cm2; P=0.007 and for RNAEFrassetto: mean difference - 0.088 g/cm2; P=0.004). Similar results were observed in a subgroup analysis of subjects with dietary calcium intake of >800 mg/day. In conclusion, a higher RNAE (i. e. more dietary acidity), which is associated with greater intake of acid-generating foods and lower intake of alkali-generating foods, may be involved in deteriorating the bone health of postmenopausal Iranian women, even in the context of adequate dietary calcium intake.

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Dietary acid–base balance and intake of bone-related nutrients in Cambridge teenagers

European Journal of Clinical Nutrition ◽

10.1038/sj.ejcn.1602006 ◽

2004 ◽

Vol 58 (11) ◽

pp. 1462-1471 ◽

Cited By ~ 25

Author(s):

C J Prynne ◽

F Ginty ◽

A A Paul ◽

C Bolton-Smith ◽

S J Stear ◽

...

Keyword(s):

Acid Base Balance ◽

Acid Base ◽

Base Balance ◽

Dietary Acid

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Impact of hydrogen ion on fasting ketogenesis: feedback regulation of acid production

AJP Renal Physiology ◽

10.1152/ajprenal.1982.242.3.f238 ◽

1982 ◽

Vol 242 (3) ◽

pp. F238-F245 ◽

Cited By ~ 2

Author(s):

V. L. Hood ◽

E. Danforth ◽

E. S. Horton ◽

R. L. Tannen

Keyword(s):

Acid Production ◽

Metabolic Regulation ◽

Feedback Regulation ◽

Hydrogen Ion ◽

Acid Excretion ◽

Acid Base Balance ◽

Acid Base ◽

Urine Ph ◽

Ion Production ◽

Base Balance

To determine whether acid-base balance regulates hydrogen ion production, seven obese volunteers were given NaHCO3 and NH4Cl (2 mmol.kg-1.day-1) during two separate 7-day fasts. On days 5-7 plasma bicarbonate was lower in the NH4Cl fasts (14.0 +/- 1.4 mM) than in the NaHCO3 fasts (18.3 +/- 1.1 mM), while urine pH and net acid excretion did not differ. Acid production (acid excretion minus intake) was greater by 204 mmol/day in the NaHCO3 fasts (274 +/- 16 mmol/day) than in the NH4Cl fasts (70 +/- 19 mmol/day). Ketoacid excretion, which reflected net ketoacid production, paralleled acid production, decreasing from 213 +/- 24 mmol/day in the NaHCO3 fasts to 67 +/- 18 mmol/day in the NH4Cl fasts. Thus, during starvation, alterations in hydrogen ion intake and the associated changes in acid-base balance modify the net production of endogenous acid by influencing the synthesis or utilization of ketoacids. Although the specific site of this metabolic regulation is undefined, these results indicate that systemic acid-base status can exert feedback control over hydrogen ion production.

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Role of organic anions in renal response to dietary acid and base loads

AJP Renal Physiology ◽

10.1152/ajprenal.1989.257.2.f170 ◽

1989 ◽

Vol 257 (2) ◽

pp. F170-F176 ◽

Cited By ~ 11

Author(s):

J. C. Brown ◽

R. K. Packer ◽

M. A. Knepper

Keyword(s):

Organic Anion ◽

Organic Anions ◽

Acid Excretion ◽

Acid Base Balance ◽

Acid Base ◽

Urine Ph ◽

Renal Response ◽

Base Balance ◽

Net Acid Excretion

Bicarbonate is formed when organic anions are oxidized systemically. Therefore, changes in organic anion excretion can affect systemic acid-base balance. To assess the role of organic anions in urinary acid-base excretion, we measured urinary excretion in control rats, NaHCO3-loaded rats, and NH4Cl-loaded rats. Total organic anions were measured by the titration method of Van Slyke. As expected, NaHCO3 loading increased urine pH and decreased net acid excretion (NH4+ + titratable acid - HCO3-), whereas NH4Cl loading had the opposite effect. Organic anion excretion was increased in response to NaHCO3 loading and decreased in response to NH4Cl loading. We quantified the overall effect of organic ion plus inorganic buffer ion excretion on acid-base balance. The amounts of organic anions excreted by all animals in this study were greater than the amounts of NH4+, HCO3-, or titratable acidity excreted. In addition, in response to acid and alkali loading, changes in urinary organic anion excretion were 40-50% as large as changes in net acid excretion. We conclude that, in rats, regulation of organic anion excretion can contribute importantly to the overall renal response to acid-base disturbances.

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Effect of Simulated Matches on Post-Exercise Biochemical Parameters in Women’s Indoor and Beach Handball

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17145046 ◽

2020 ◽

Vol 17 (14) ◽

pp. 5046

Author(s):

Joanna Kamińska ◽

Tomasz Podgórski ◽

Jakub Kryściak ◽

Maciej Pawlak

Keyword(s):

Blood Parameters ◽

Ion Concentration ◽

Electrolyte Balance ◽

Acid Base Balance ◽

Acid Base ◽

Urine Ph ◽

Physically Active ◽

Post Exercise ◽

Before And After ◽

Base Balance

This study assesses the status of hydration and the acid-base balance in female handball players in the Polish Second League before and after simulated matches in both indoor (hall) and beach (outdoor) conditions. The values of biochemical indicators useful for describing water-electrolyte management, such as osmolality, hematocrit, aldosterone, sodium, potassium, calcium, chloride and magnesium, were determined in the players’ fingertip capillary blood. Furthermore, the blood parameters of the acid-base balance were analysed, including pH, standard base excess, lactate and bicarbonate ion concentration. Additionally, the pH and specific gravity of the players’ urine were determined. The level of significance was set at p < 0.05. It was found that both indoor and beach simulated matches caused post-exercise changes in the biochemical profiles of the players’ blood and urine in terms of water-electrolyte and acid-base balance. Interestingly, the location of a simulated match (indoors vs. beach) had a statistically significant effect on only two of the parameters measured post-exercise: concentration of calcium ions (lower indoors) and urine pH (lower on the beach). A single simulated game, regardless of its location, directly affected the acid-base balance and, to a smaller extent, the water-electrolyte balance, depending mostly on the time spent physically active during the match.

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Determination of NABE in urine of high-yield dairy cows in early lactation in conditions of moderate heat stress

Veterinarski glasnik ◽

10.2298/vetgl1006349f ◽

2010 ◽

Vol 64 (5-6) ◽

pp. 349-358

Author(s):

Natalija Fratric ◽

Ivan Vujanac ◽

Horea Samanc ◽

Danijela Kirovski ◽

Dragan Gvozdic ◽

...

Keyword(s):

Heat Stress ◽

Dairy Cows ◽

High Yield ◽

Early Lactation ◽

Acid Base Balance ◽

Acid Base ◽

Urine Ph ◽

Base Balance ◽

Daily Milk Production

The work presents the results of investigations of the effect of moderate heat stress on the acidobasal status in high-yield dairy cows in early lactation. Improving performance in high-yield dairy cows increases their inclination toward metabolic disorders. The most likely to be affected is the acid-base balance, in particular when cows are exposed to heat stress. Investigations so far have shown that the taking of urine samples and their analysis is the best and fastest way to diagnose disorders in the acid-base balance. Investigations were carried out on 7 clinically healthy cows of the Holstein- Friesian breed in the phase of early lactation, 30 to 40 days (on days 30, 33 and 40 ) following calving during the summer period, during the month of July, when there were significant variations in daily and nightly temperatures. The cows were in the second and fourth lactation, the annual milk yield was 8000 L milk per cow. The average daily milk production in the early phase of lactation ranged from 35 to 40 L. The cows were fed mixed rations (TMR) twice daily. Lucerne hay in limited quantities was given to the cows prior to the mixed feed ration. The ration for this animal category was optimized on the grounds of the daily milk production. The balance of cations and anions in the feed ration stood at 95 mEq/kg DM. The results clearly demonstrate the cows' response to moderate heat stress through the defense parameters in urine (urine pH, NABE (net-acid-base-excretion), acids, bases, ammonium ion (NH4). The determination of the kidney NABE yields more correct data than the urine pH on acidotic conditions. The results of examinations of the urine pH do not show any digressions from physiological values and are approximately the same in all cows during the investigated periods. Normal NABE values are from 100-200 mmol/L. Burdening with acid products results in a NABE range from 0-100mmol/L, and metabolic acidosis results in NAB<0 mmol/L. NABE in the cows in this experiment revealed that the organism is burdened by acid metabolic products and it stood at 58.28?27.96 mmol/L on day 30, 69.28?29.89 mmol/L on day 33, and 60.60?26.88mmol/L on day 40. Consequently, it seems that NABE values are decreased in cases of acidosis due to stepped up H+ excretion and stepped up bicarbonate reabsorption.

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Associations between Dietary Acid Load and Biomarkers of Inflammation and Hyperglycemia in Breast Cancer Survivors

Nutrients ◽

10.3390/nu11081913 ◽

2019 ◽

Vol 11 (8) ◽

pp. 1913 ◽

Cited By ~ 4

Author(s):

Tianying Wu ◽

Phoebe Seaver ◽

Hector Lemus ◽

Kathryn Hollenbach ◽

Emily Wang ◽

...

Keyword(s):

Breast Cancer ◽

Metabolic Acidosis ◽

Cancer Survivors ◽

Breast Cancer Survivors ◽

Acid Base Balance ◽

Acid Base ◽

Dietary Acid Load ◽

Base Balance ◽

Dietary Acid ◽

Acid Load

Metabolic acidosis can lead to inflammation, tissue damage, and cancer metastasis. Dietary acid load contributes to metabolic acidosis if endogenous acid–base balance is not properly regulated. Breast cancer survivors have reduced capacities to adjust their acid–base balance; yet, the associations between dietary acid load and inflammation and hyperglycemia have not been examined among them. We analyzed data collected from 3042 breast cancer survivors enrolled in the Women’s Healthy Eating and Living (WHEL) Study who had provided detailed dietary intakes and measurements of plasma C-reactive protein (CRP) and hemoglobin A1c (HbA1c). Using a cross-sectional design, we found positive associations between dietary acid load and plasma CRP and HbA1c. In the multivariable-adjusted models, compared to women with the lowest quartile, the intakes of dietary acid load among women with the highest quartile showed 30–33% increases of CRP and 6–9% increases of HbA1c. Our study is the first to demonstrate positive associations between dietary acid load and CRP and HbA1c in breast cancer survivors. Our study identifies a novel dietary factor that may lead to inflammation and hyperglycemia, both of which are strong risk factors for breast cancer recurrence and comorbidities.

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Erratum: Dietary acid–base balance and intake of bone-related nutrients in Cambridge teenagers

European Journal of Clinical Nutrition ◽

10.1038/sj.ejcn.1602069 ◽

2004 ◽

Vol 58 (11) ◽

pp. 1558-1558 ◽

Cited By ~ 1

Author(s):

C J Prynne ◽

F Ginty ◽

A A Paul ◽

C Bolton-Smith ◽

S J Stear ◽

...

Keyword(s):

Acid Base Balance ◽

Acid Base ◽

Base Balance ◽

Dietary Acid

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Influence of Acid-Base Balance on Efficacy and Toxicity of Drugs

Proceedings of the Royal Society of Medicine ◽

10.1177/003591576505811p204 ◽

1965 ◽

Vol 58 (11P2) ◽

pp. 961-963 ◽

Cited By ~ 20

Author(s):

M D Milne

Keyword(s):

Practical Importance ◽

Physiological Property ◽

Water Soluble ◽

Weak Acids ◽

Acid Base Balance ◽

Acid Base ◽

Urinary Ph ◽

Alkaline Urine ◽

Base Balance ◽

Ph Dependent

Changes in acid-base balance have a profound influence on many aspects of the action of drugs. This is illustrated by data on the absorption of drugs from the stomach and intestine, in changes in distribution of drugs between plasma and cells, and the effect of change in urinary pH. As a general principle, these changes in the pharmacology of weak acids and bases are governed by physicochemical principles, which influence the proportion of the ionized and unionized components according to the pH of the medium and also to the peculiar property of biological membranes which allow the free passage of the lipoid-soluble unionized component and impede transfer of the water-soluble ionized fraction. Lipoid-soluble weak acids are excreted at higher clearances in alkaline urine, and conversely weak bases in acid urine. This is shown to be of practical importance in the treatment of poisoning, in the diagnosis of addiction to drugs and in studies of drug metabolism. In general, the excretion of natural metabolites is less likely to be influenced by urinary pH, as these substances are usually less lipoid-soluble than many widely used drugs. pH-dependent excretion is, however, of practical importance in relation to the urinary content of many indolic metabolites and also in the excretion of pigments derived from the degradation of hæmoglobin. Urobilinogen excretion is certainly pH-dependent, a higher clearance rate occurring in alkaline urine. However, work is necessary to decide whether some of the porphyrins also show this important physiological property.

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