Body pH; acid-base balance and alkaline diet
Body pH; acid-base balance and alkaline diet
by: Millie Lytle, ND, MPH, CNS
You may have heard that balancing your body pH with an Alkaline Ash or alkalizing diet may provide good nutrition for you. PH stands for the “potential of Hydrogen” and inversely measures the concentration of hydrogen ions per cubic area of a substance. A lower pH means more hydrogen. What this means to you and me is the pH scale measures acidity (below 7) and alkalinity (above 7) with neutral pH being 7. You may have heard that cancer cells don’t grow in alkalinity whereas they proliferate in an acid environment. You may know that acid-base balance is important for your health. You may have read that you can reduce your cancer risk by increasing the pH of your body fluids via food and supplementation. Someone may have told you that Litmus paper strips are available in the pharmacy and vitamin store. They measure the pH of water, your blood, saliva and urine. If you have heard any of these tidbits, you have heard correctly.
Pure water has a pH of 7, which is neutral. Human blood is slightly alkaline with a constant pH of 7.4. If blood pH goes up then the person will suffer from metabolic alkalosis. If the blood pH goes down then metabolic acidosis will result, a medical condition whereby the body either makes too much acid or does not clear acid from the kidneys. If the blood pH falls below 7.35 then acidemia, a potentially fatal condition, results. Metabolic acidosis can also be the result of consuming a diet low in alkaline foods that would leave the blood pH lower than 7.4 but higher than 7.35.
Acid-base balance is maintained by complex mechanisms called human homeostasis. Homeostasis is a sophisticated multi-tasking system whereby the body’s chemical and hormonal interactions work to maintain a balance, above all else, by continually correcting for and returning functioning within a normal range. Fluid regulation and osmolality are key functions of homeostasis that affect body’s acid-base balance, blood pressure, blood volume, extracellular volume and more. The primary organs responsible for homeostasis are the liver, kidneys, brain and endocrine system, which auto-correct for changes that support physical and psychological health. If the body suffers homeostatic imbalance, then death or disease may occur such as heart attack, osteoporosis, diabetes, dehydration or gout. If the body cannot clear harmful substances from the bloodstream, such as infection or sepsis, this may be considered a result of homeostatic imbalance, as well. At certain times, the body will compensate for physical or nutritional deficiencies in order to preserve the life of the individual. Homeostasis, in prioritizing survival, may sacrifice the health of one or several body systems. In fact, some organs may suffer over time as a result of normal homeostasis and disease can still result.
While the body works to maintains homeostasis, it is continually influenced by various factors such as medications, heavy metals, chemical exposures and nutrition. Nutritional deficiencies can interrupt homeostasis mechanisms and lead to inadvertent disease. Diet-induced metabolic acidosis, as a result of mineral deficiencies, has been theorized to be largely responsible for causing many common chronic diseases due to their effect on the body’s homeostasis1. What’s more, the Standard American (SAD) diet is considered acidogenic due to the high dietary acid load from meat, refined wheat and other grains, sugar and low in alkalizing dietary minerals such as potassium, magnesium and calcium2. The SAD diet sets many Americans up for illness over their lifetime, but the good news is many of these diseases are preventable with nutrition and lifestyle changes.
Blood pH and Antacid Medication
Although the blood needs to be alkaline, the stomach needs to be acid. An acid stomach with a pH of 1-3 is a normal and healthy state. Stomach acid is required in order to breakdown proteins, produce B12 and prevent bacterial illness such as food poisoning, H Pylori and intestinal parasites. Acid reflux or GERD is a result of acid being irregularly produced away from food due to stress, cigarettes, or acidic foods such as alcohol, cola, and coffee. Acid, then, splashes up into the esophagus from a weak or faulty esophageal sphincter; a muscle that acts like a valve but is not actually a valve. Many people take over-the-counter and prescription acid reducers to soothe reflux pain and lesions. New studies show, however, that long-term use of strong acid-lowering medications (cimetidine, ranitidine, omeprazole) may cause a host of problems including osteoporosis and higher chances of hip and thigh fractures, even when taking medications to reduce bone loss called bisphosphonates (Fosamax, Boniva, Actonel, Reclast, etc.)4. Although antacids produce an alkaline environment in the stomach, they ironically contribute to metabolic acidosis. Antacids contain aluminum that increases calcium excretion in the urine and lead to mineral deficiencies. In order to maintain pH in the blood, the bones respond by releasing calcium into the blood to balance the loss of calcium through the urine. Over time, the bones thin and weaken. In this study, those who used antacids regularly but less than once a day had a 12% higher fracture risk, a pill a day caused a 30% increased chance of fracture and most significantly, those who took more than one antacid per day had an increased risk of fracture of 41% over those who do not take any antacids4.
Some suggestions for a natural approach to heartburn (that maintains proper calcium levels in the bone) 1) demulcents herbs such as DGL, plantain, marshmallow and slippery elm to sooth mucous membranes and promote healing before meals and prior to lying down, 3) a handful of raw almonds as a source of acid buffering calcium carbonate as needed, 4) digestive enzymes with papain and bromelain to digest protein food and support normal stomach acid production to eliminate gas and bloating after a meals. Lifestyle approaches are also important, such as avoiding spicy and acidic foods, practicing stress relief and smoking-cessation.
Urine pH and Alkaline Diets
While metabolic acidosis is concerned with the pH of the blood, it is not a necessarily a good measurement of body mineral level because homeostatic mechanisms work to ensure a constant pH. Urinary pH has been shown to be a good indicator of nutritional mineral status both in population studies as well as clinical trials. Alternative health providers have been testing urinary pH as an indicator of physiological health and correcting it through diet and supplementation for the last century. As urine pH relates to dietary acid-base load, it has been proven as a useful tool to monitor change in consumption of fruit and vegetables in individuals2,6. Population-based research started investigating these areas of nutrition after 2001, with the Framingham Osteoporosis Study (2001)1 and the European Prospective Investigation into Cancer and Nutrition (EPIC, 2002)2. Results of both epidemiological studies showed an alkaline-generating diet with higher fruit and vegetable and lower meat intake are related to more alkaline urine1,2. A Dutch clinical study also showed that ingestion of a multi-mineral supplement is associated with both a significant increase in blood and urinary pH3. Read more below.
Urinary pH and Bone Mineralization
Bone is an example of a body tissue that can suffer in order to maintain normal levels of minerals in the blood (to maintain proper pH). In cases of nutritionally-related metabolic acidosis, there are not enough available minerals in the blood from the diet so the pH falls between 7.4 and 7.35. This type of metabolic acidosis has been targeted as a key etiology in the onset of many nutritionally related chronic diseases such as osteoporosis3. When the pH falls, the blood pulls calcium and magnesium out of the bones to normalize and correct the acidic pH. When bone cannot maintain normal levels of minerals, if suffers from chronic degenerative change over time, such as demineralization, bone loss and ultimately osteoporosis. Calcium and vitamin D are both approved by the FDA as necessary for bone health.
“Adequate calcium and vitamin D throughout life, as part of a well-balanced diet, may reduce the risk of osteoporosis.” - FDA
Other nutrients have also been identified as necessary for proper calcium utilization and bone quality such as protein, vitamins K, K2, C and B complex, magnesium and silica. While vitamins C and B complex, zinc, selenium, boron and copper and strontium have also shown research promise for bone strength5.
Evidence exists that a more acidic diet is detrimental to bone health. A large population study (22,034 men and women aged 39-78 years old) first proved a relationship between urine pH and dietary acid-base load as influenced by servings of food groups. A sub-study done on 363 people compared pH in casual and 24 hour urine samples to food intakes from a 7 day diary and the Food Frequency Questionnaire. A more alkaline diet (high fruit and vegetable intake and lower consumption of meat) was significantly associated with a more basic urine pH. When adjusted for age, Body Mass Index (BMI), physical activity and smoking habit, high fruit and vegetables intake and low meat intake still predicted alkaline urine. Also excluded were the following variables; urinary protein, glucose, ketones, diagnosed high blood pressure and diuretic medication6. The 7 day diet diary and a 24 hour urinalysis was the best combination indicator of pH. Although more precise methods exist for measurement of acid-base balance, urine pH reflects acid-base balance and is readily measurable at home.
If you want to test your urine pH then measure all urine collected over a 24 hour period. In order to increase the pH, eat over 6 servings of mineral-rich fruits and vegetables per day, as well as dietary supplements, for 7 days and measure the pH of all urine collected over a 24 period.
Urinary pH and Electrolytes
Electrolytes are minerals that help maintain alkaline pH and hydration first in the intestines and then in the rest of the blood and tissues. Electrolytes include magnesium, potassium, calcium, sodium and bicarbonate. Previous investigations have reported beneficial effects of dietary potassium and potassium-rich foods and mineral water on bone health. In some rat studies, it has been shown that supplementation with alkaline minerals neutralizes diet-induced metabolic acidosis and is related to higher bone density7. In addition, potassium bicarbonate has been shown to reduce calcium excretion in the urine of postmenopausal women8. Another study indicated that bone resorption (loss) was reduced and bone formation was increased following potassium bicarbonate intake in post-menopausal women9. An acid pH destroys bone by increasing the number of osteoclasts (cells that destroy bone), as well as inhibits bone matrix mineralization10. High fruit and vegetable intake and dietary supplements containing alkalizing minerals have been, in contrast, shown to increase the pH of the blood and urine (and saliva) when taken acutely as well as over a long period of time. Taking a multi-mineral dietary supplement significantly increases the pH of the blood and urine. Adequate levels of magnesium, potassium and calcium in the blood are beneficial to address muscle cramping by reducing neuropathy and nerve pain.
Urinary pH, Uric Acid Levels and Electrolytes
Uric acid is a metabolic result of the breakdown of purine nucleotides. A high blood concentration is associated with gout, kidney stones and diabetes. An alkaline diet that results in alkaline urine facilitates the excretion of uric acid11. Though this may read counter-intuitive it is so because foods containing high levels of alkalizing minerals have fewer purine bodies than acidifying foods. A study was conducted for the Japanese government health promotion program whereby acid diet and alkaline diets were given to healthy female students in a 5-day crossover study. The study collected urine volumes and measured pH, uric acid, creative and all mineral levels (alkaline cations and acidic anions). After 3 days on either the acidic or alkaline diet, urinary pH stabilized to indicate acidic or alkaline. Results showed that the amount of organic acid generated consistent with the pH of the diet, indicating that hydrogen ions in urine is generated by the metabolic breakdown of food materials. The more uric acid excreted, the higher the urine pH. Uric acid in the blood was higher in the acidic group than the alkaline group, pointing towards metabolic acidosis. There were noticeable differences between acidic and alkaline diets in the uric acid concentration in serum as well as in urine; uric acid in the serum was higher in the acidic group than in the alkaline group, while urinary uric acid was lower in the acidic than the alkaline group. These changes of uric acid in acidic urine and in serum were reflected in the reduction of its clearance. From these observations, it is considered that uric acid may be reabsorbed in the bloodstream of those with more acidic urine than alkaline urine. Whereas an acidic diet raises uric acid in the blood and decreases output in the urine. The researchers thus proved that alkalization of urine by eating nutritionally well-designed alkaline diet, such as diets high in vegetable and fruit and less animal protein, is effective for removing uric acid from the body12. Patients with uric acid calculus, calcium oxalate and those without urinary calculus were compared for their metabolic status. In addition to low fruit and vegetable intake, low urinary pH, low daily water intake, eating more salted and animal food, were very closely associated with uric acid calculus and calcium oxalate patients. Blood potassium and magnesium were higher in the control group than in the calculi groups13. Novel drug research has studied the effects of dietary seaweed extracts on the levels of urinary calcium oxalate in inhibition of calcium oxalate stone formation and excretion14.
Muscle pH; Brief Muscle and Heart Pathophysiology
The University of Mississippi Medical Center lists that the cellular pH in resting skeletal muscle is typically 7.15. During exercise, as alkalizing minerals are utilized, pH falls in proportion to the intensity of the exercise. Lactic acid concentrations along with carbon dioxide contribute to the lower pH. Minerals are required to normalize the pH following exercise. If a balance of magnesium, potassium, sodium and calcium are not replenished adequately this leaves electrolyte deficits that can contribute to abnormal muscle function. Based on the normal physiology of the skeletal muscles as well as the heart muscle, muscles require a substantial concentration of available alkalizing minerals to fire and function smoothly, maintain regular blood flow to the cell and reduce tension. In an acidic environment, muscular inflammatory response can lead to lack of recovery and other symptoms including pain, numbness, and even paralysis (tetany). Increasing potassium and magnesium levels through supplementation can reduce muscle pain and tension in people with Gitelman’s Syndrome, a genetic metabolic alkalosis characterized by low blood potassium, low urinary calcium and low blood magnesium15 as well as people with normal mineral physiology. Thiazide diuretics can also cause these same muscle symptoms15.
Blood pressure physiology involves the mineral balance of minerals sodium, potassium, magnesium, chlorine and calcium. Health promotion efforts from public health departments have highlighted the importance for the population to eat a low salt diet, but have not emphasized the importance to balance salt intake with more alkalizing minerals such as potassium, calcium and magnesium. When these minerals are relatively low in the diet, the negative effects of sodium chloride (salt) become dire. In an acidic environment blood pressure rises, heart beat becomes irregular and cardiac events can result. Increasing potassium and magnesium levels through supplementation can nutritionally support the over-excitability of the heart15. Men who die of a sudden ischemic heart attack may have the very low levels of magnesium and potassium in the heart muscle as compared to others who did not die16.
It is important to eat a diet high in vegetables, sea greens and consume dietary supplements with alkalizing minerals such as calcium, magnesium and potassium in order to avoid diet-induced metabolic acidosis. Avoiding antacid medications preserves an alkaline pH in the blood and protects bones from demineralization. Similarly, eating an alkalizing diet rich in fruits, vegetables and minerals increases the pH of the blood and preserves bone. A diet rich in mineral electrolytes prevents inflammation of the nervous tissue as well as maintains strong and flexible muscles. Maintaining a high blood and urine pH as well as consuming an adequate water intake prevents high uric acid levels in the blood. Regular and adequate consumption of green vegetables, seaweeds and alkalizing minerals maintains normal urinary function and may contribute to disease-reduction in those with diabetes, kidney stones and gout. Muscle pain and rigidity in the heart and skeletal muscle impedes normal function when associated with mineral deficiencies; be they congenital, drug-induced, sport-related or nutritional. Eating a diet rich in alkaline minerals is imperative to homeostasis, beneficial to many organ systems and can mediate many chronic diseases. One can measure their own body pH easily with Litmus paper over 24 hour urine collection.
- Tucker KL, Hannan MT, Kiel DP. The acid-base hypothesis: diet and bone in the Framingham Osteoporosis Study. Eur J Nutr. 2001 Oct;40(5):231-7.
- Agudo A, Slimani N, Ocké MC, Naska A, Miller AB, Kroke A, Bamia C, Karalis D, Vineis P, Palli D, Bueno-de-Mesquita HB, Peeters PH, Engeset D, Hjartåker A, Navarro C, Martínez Garcia C, Wallström P, Zhang JX, Welch AA, Spencer E, Stripp C, Overvad K, Clavel-Chapelon F, Casagrande C, Riboli E. Consumption of vegetables, fruit and other plant foods in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohorts from 10 European countries. Public Health Nutr. 2002 Dec;5(6B):1179-96.
- König D, Muser K, Dickhuth HH, Berg A, Deibert P. Effect of a supplement rich in alkaline minerals on acid-base balance in humans. Nutr J. 2009 Jun 10; 8:23.
- de Vries F, Cooper AL, Cockle SM, van Staa TP, Cooper C. Fracture risk in patients receiving acid-suppressant medication alone and in combination with bisphosphonates. Osteoporosis Int. 2009 Dec;20(12):1989-98.
- Rondanelli M, Opizzi A, Perna S, Faliva MA. Update on nutrients involved in maintaining healthy bone. Endocrinol Nutr. 2013 Apr;60(4):197-210.
- Welch AA, Mulligan A, Bingham SA, Khaw KT. 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. Br J Nutr. 2008 Jun;99(6):1335-43. Epub 2007 Nov 28.
- Mardon J, Habauzit V, Trzeciakiewicz A, Davicco MJ, Lebecque P, Mercier S, Tressol JC, Horcajada MN, Demigné C, Coxam V: Long-term intake of a high-protein diet with or without potassium citrate modulates acid-base metabolism, but not bone status, in male rats. J Nutr 2008, 138:718-24.
- Frassetto L, Morris RC Jr, Sebastian A: Long-term persistence of the urine calcium-lowering effect of potassium bicarbonate in postmenopausal women. J Clin Endocrinol Metab 2005, 90:831-4.
- Sebastian A, Harris ST, Ottaway JH, Todd KM, Morris RC Jr: Improved mineral balance and skeletal metabolism in postmenopausal women treated with potassium bicarbonate. N Engl J Med 1994, 330:1776-81.
- Arnett TR: Extracellular pH regulates bone cell function. J Nutr 2008, 138:415S-8S.
- Kanbara A, Seyama I. Effect of urine pH on uric acid excretion by manipulating food materials. Nucleosides Nucleotides Nucleic Acids. 2011 Dec;30(12):1066-71.
- Kanbara A, Miura Y, Hyogo H, Chayama K, Seyama I. Effect of urine pH changed by dietary intervention on uric acid clearance mechanism of pH-dependent excretion of urinary uric acid. Nutr J. 2012 Jun 7;11:39.
- Chong HH, An G. [Percentage of uric acid calculus and its metabolic character in Dongjiang River valley]. Zhonghua Wai Ke Za Zhi. 2009 Feb 15;47(4):248-51.
- Deng SP, Ouyang JM. [Modulation of polysaccharide extracted from Laminaria on phase compositions of urinary crystal calcium oxalate].[Article in Chinese] Guang Pu Xue Yu Guang Pu Fen Xi. 2007 Nov;27(11):2371-4.
- Yildiz M, Yildiz BS, Karakoyun S, Cakal S, Sahin A, Aladag NB. The effects of serum potassium and magnesium levels in a patient with Gitelman's syndrome on the timing of ventricular wall motion and the pattern of ventricular strain and torsion. Echocardiography. 2013 Feb;30(2):E47-50.
- Johnson CJ, Peterson DR, Smith EK. Myocardial tissue concentrations of magnesium and potassium in men dying suddenly from ischemic heart disease. Am J Clin Nutr. 1979 May;32(5):967-70