To recap, pH is the acronym for potential hydrogen. It is a measure of the degree of saturation of the hydrogen ion in a substance or solution.
If water and water is combined we get H2O + H2O => H3O + OH–
H3O (the hydronium ion+) is the acid element and OH– (the hydroxyl ion–) is the base or alkaline element. (You may also note that the +ion is a cation and the -ion is an anion as discussed in the section on Zeta Potential.) In pure water these are balanced and upon measuring with a pH meter the reading would be 7.
7 is neutral on a pH scale which goes from 0 to 14. This scale corresponds to the hydrogen ion concentration from 100 to 10-14 moles per liter. This is a huge range, which sensitive instruments can measure.
When the H3O and OH– are out of balance a pH meter will detect this and the reading will move above or below 7. Like a teeter-totter, if one goes up the other goes down and vice versa.
In the human body a pH-balancing act is continuously going on to maintain homeostasis. When defining measurement values of certain pH levels of human fluids, there are no absolutes that can be written in stone because the value that “should be here” has to be balanced against other values “that should be there”. In essence, in the human body things never happen in a vacuum and you need to be ever mindful of these things as you make your measurements.
What is pH?
On the pH scale, which ranges from 0 on the acidic end to 14 on the alkaline end, a solution is neutral if its pH is 7. At pH 7, water contains equal concentrations of H+ and OH- ions. Substances with a pH less than 7 are acidic because they contain a higher concentration of H+ ions. Substances with a pH higher than 7 are alkaline because they contain a higher concentration of OH- than H+.
The pH scale is a log scale so a change of one pH unit means a tenfold change in the concentration of hydrogen ions. In this light, you can see how a slight change in your pH value can have a great impact on your internal environment and, ultimately, your health.
Importance of Balancing pH
Living things are extremely sensitive to pH and function best (with certain exceptions, such as certain portions of the digestive tract) when solutions are nearly neutral. Most interior living matter (excluding the cell nucleus) has a pH of about 6.8.
Actually a healthy body is slightly alkaline measuring approximately 7.4. This ideal blood 7.4 pH measurement means it is just slightly more alkaline than acid.
In the absence of oxygen, glucose undergoes fermentation to lactic acid. This causes the pH of the cell to drop from between 7.3 to 7.2 down to 7 and later to 6.5 in more advanced stages of cancer and in metastases the pH drops to 6.0 and even 5.7 or lower.
Our bodies simply cannot fight disease if our body pH is not properly balanced. It has been determined that an alkaline body is more conducive to health and well-being than an acidic one. An undesirable pH can lead to a variety of negative health effects.
A body that tends toward acidity heightens the risk for infections from bacteria, yeast, parasites, and viruses. All of these “critters” seek out and thrive in an acid environment. Not only are you more susceptible to infections such as colds and the flu, degenerative diseases like cancer, arthritis, heart disease and osteoporosis are promoted if your pH is consistently acid. If disease is to be prevented or successfully managed, an acid pH must be overcome.
Testing your pH
To perform this simple test, all you need is a roll of pH testing paper (preferably pHydrion test paper), a plastic spoon, and some fresh saliva! The test uses a pH-sensitive, color-coded test strip to reveal your personal pH status.
For the saliva test: Be sure not to eat, drink, or brush your teeth for 30 minutes prior to the test. Swallow a couple of times to clear the mouth and stimulate new saliva. Then discharge some saliva into a PLASTIC spoon (it is recommended NOT to touch the pH paper to your tongue due to the chemicals in the paper.
Tear off a one-inch strip of pH paper, place into saliva and let sit. After approximately 30 seconds, compare the color of your immersed pH paper with the color chart provided on the pH testing roll. The lower your pH value below 7.0, the greater your degree of acid stress.
Continue testing and recording your pH for a few weeks – first thing in the morning and at bedtime (This will show your personal pH trend).
The pH of your blood must remain between 7.35 and 7.45.
If your blood’s pH rises or falls one tenth of a pH unit, it’s cause for a visit to a hospital’s intensive care unit.
If blood pH moves two tenths either way, it’s lethal.
Salivary pH Test:
While generally more acidic than blood, salivary pH mirrors the blood ( if not around meals ) and is also a fairly good indicator of health. It tells us what the body retains.
Salivary pH is a fair indicator of the health of the extra cellular fluids and their alkaline mineral reserves. Optimal pH for saliva is 6.4 to 6.8. A reading lower than 6.4 is indicative of insufficient alkaline reserves.
After eating, the saliva pH should rise to 7.8 or higher. Unless this occurs, the body has alkaline mineral deficiencies ( mainly Calcium and Magnesium ) and will not assimilate food very well. To deviate from ideal salivary pH for an extended time invites illness. If your saliva stays between 6.4 and 6.8 all day, your body is functioning within a healthy range.
The pH of the urine indicates how the body is working to maintain the proper pH of the blood. The urine reveals the alkaline building (anabolic) and acid tearing down (catabolic) cycles. The pH of urine indicates the efforts of the body via the kidneys, adrenals, lungs and gonads to regulate pH through the buffer salts and hormones.
Urine can provide a fairly accurate picture of body chemistry, because the kidneys filter out the buffer salts of pH regulation and provide values based on what the body is eliminating. Urine pH can vary from around 4.5 to 9.0 for its extremes, but the ideal range is 5.8 to 6.8. If your urinary pH fluctuates between 6.0 – 6.4 in the morning and 6.4 – 7.0 in the evening, your body is functioning within a healthy range.
Balancing your pH
‘Acidosis’ for an extended time in the acid pH state, can result in rheumatoid arthritis, diabetes, lupus, tuberculosis, osteoporosis, high blood pressure, most cancers and many other diseases.
Ways to increase your alkalinity:
1). Eat raw fruits and vegetables in the most alkaline range.
2). Remove strong acidifiers from the diet such as sodas, whole wheat, caffeine, tobacco, black tea, alcohol and red meat.
There is a large and growing body of scientific evidence as to the importance of body pH to good health and wellbeing, and the challenges our bodies face in keeping it in balance. Here is a selected list of some of the peer-reviewed articles.
- 1. Adrogue, H. and Madias, N. Management of life-threatening acid-base disorders, New England Journal of Medicine 338: 26-34, 1998.
Acid-base homeostasis exerts a major influence on protein function, thereby critically affecting tissue and organ performance. Deviations in body acidity can have adverse consequences and when severe, can be life-threatening.
2. Alpern, R. Trade-offs in the adaptation to acidosis, Kidney International 47: 1205-1215, 1995.
Excessive dietary intake of protein with consequent increase in metabolic acid production result in compensatory mechanisms that lead to progression of kidney stones, bone disease, renal disease and a catabolic state.
3. Alpern, R. and Sakhaee, K. The clinical spectrum of chronic metabolic acidosis: homeostatic mechanisms produce significant morbidity, American Journal of Kidney Disease 29: 291-302, 1997.
Chronic metabolic acidosis is a process whereby an excess acid load is placed on the body due to excess acid generation or diminished acid removal by normal homeostatic mechanisms. Excessive meat ingestion and aging are two clinical conditions often associated with chronic metabolic acidosis. The body’s homeostatic response to this pathology is very efficient. Therefore, the blood pH is frequently maintained within the “normal” range. However, these homeostatic responses engender pathologic consequences such as nephrolithiasis, bone demineralization, muscle protein breakdown and renal growth.
4. Bushinsky, D. Acid-base imbalance and the skeleton, European Journal of Nutrition 40: 238-244, 2001.
Humans generally consume a diet that generates metabolic acids leading to a reduction in the systemic bicarbonate and a fall of pH. Chronic metabolic acidosis alters bone cell function; there is an increase in osteoclastic bone resorption and a decrease in osteoblastic bone formation. As we age, we are less able to excrete metabolic acids due to the normal decline in renal function.
5. Frassetto, L.; Morris, R.; Sellmeyer, D.; Todd, K. and Sebastian, A. Diet, evolution and aging: the pathophysiologic effects of the post-agricultural inversion of the potassium-to-sodium and base-to-chloride ratios in the human diet, European Journal of Nutrition 40:5 200-213, 2001.
Dietary changes over the last two centuries have resulted in a mismatch between genetically-determined nutritional requirements in humans. Excess sodium chloride, a deficiency of potassium and excess dietary acids that are not mediated by dietary bicarbonates lead to chronic low-grade metabolic acidosis that amplifies the age-related pathophysiological consequences in humans (such as loss of bone substance, increase in urinary calcium, disturbance in nitrogen metabolism, and low levels of growth hormone).
6. Frassetto, L.; Morris, R. and Sebastian, A. Effect of age on blood acid-base composition in adult humans: role of age-related renal functional decline, American Journal of Physiology, 271: 1114-22, 1996.
Otherwise healthy adults manifest a low-grade, diet-dependent metabolic acidosis, the severity of which increases with age at constant rate described by an index of endogenous acid production, apparently due in part, to the normal age-related decline of renal function. 7. Frassetto, L. and Sebastian, A. Age and systemic acid-base equilibrium: analysis of published data, Journal of Gerontology, Advanced Biological Science and Medical Science, 51: B91-99, 1996.
Authors examined peer-reviewed literature to determine whether systemic acid-base equilibrium changes with aging in normal adults humans. Using linear regression analysis, they found that with increasing age, there is a significant increase in the steady-state blood H+ indicating a progressively worsening low-level metabolic acidosis in what may reflect, in part, the normal decline of renal function with increasing age.
8. Krapt, R. and Jehle, A. Renal function and renal disease in the elderly, Schweizerische Medizinische Wochenschrift, 130:11 398-408 2000.
Age-induced decline in renal functions explains, at least in part, clinically important age-related conditions including metabolic acidosis.
9. Lonergan, E. Aging and the kidney: adjusting treatment to physiologic change, Geriatrics 43: 27-30, 32-33, 1988.
Changes in renal physiology and function with aging put the elderly patient at risk for adverse effect of drug therapies due to the incidence of common problems like metabolic acidosis.
10. Maurer, M.; Riesen, W.; Muser, J.; Hulter, H. and Krapf, R. Neutralization of Western diet inhibits bone resportion independently of K intake and reduces cortisol secretion in humans, American Journal of Physiology and Renal Physiology 284: F32-40, 2003.
The acid load inherent in the Western diet results in mild chronic metabolic acidosis in association with a state of cortisol excess. An alkali balanced diet modulates bone resorption and the associated alterations in calcium and phosphate homeostasis.
11. May, R.; Kelly, R. and Mitch, W. Metabolic acidosis stimulates protein degradation in rat muscle by glucocorticoid-dependent mechanism, Journal of Clinical Investigations 77:614-621, 1986.
Chronic metabolic acidosis increases net muscle protein degradation in rat muscle tissue.
12. Meghji, S.; Morrison, M.; Henderson, B. and Arnett, T. pH dependence of bone resoption: mouse calvarial osteoclasts are activated by acidosis, American Journal of Physiological and Endocrinological Metabolism 280: E112-E119, 2001.
Osteoclast activity is modulated by small pH changes and is a key determinant of bone resorption in mouse calvarial cultures.
13. Nabata, T.; Morimoto, S. and Ogihara, T. Abnormalities in acid-base balance in the elderly, Nippon Rinsho 50: 2249-53, 1992.
Decline in the ability to adjust acid-base balance is a feature of aging. Regulation of pH ultimately depends on the kidneys and lungs, however, the ability of these organs is decreased with physiological aging. Renal insufficiency and/or chronic obstructive pulmonary disease and various drugs, such as diuretics, often affect the acid-base balance in the elderly.
14. Robergs, R. Exercise-induced metabolic acidosis: where do the protons come from?, Sport Science 5(2) sportsci.org/jour/0102/rar.thm, 2001.
The physiology of intense exercise that produces acidosis is far more complex than originally thought. In the transition to higher exercise intensity, proton release is even greater than lactate production which indicates acidosis is only partially related to production of “lactic acid.”
15. Sebastian, A.; Harris, S.; Ottaway, J.; Todd, K. and Morris, R. Improved mineral balance and skeletal metabolism in postmenopausal women treated with potassium bicarbonate, New England Journal of Medicine 330:25 1776-81 1994.
Endogenous acid produced by the metabolism of foods in ordinary diets abundant in proteins may contribute to the decrease in bone mass that occurs normally with aging. The oral administration of potassium bicarbonate at a dose sufficient to neutralize endogenous acid improves calcium and phosphorus balance, reduces bone resorption and creases the rate of bone formation.
16. Sebastian, A.; Frassetto, L.; Sellmeyer, D.; Merriam, R. and Morris, R. Estimation of the net acid load of the diet of ancestral preagricultural Homo sapiens and their hominid ancestors, American Journal of Clinical Nutrition 76:6 1308-1316, 2002.
Estimates of the net systemic load of acid in ancestral pre-agricultural diets as compared to contemporary diets reflect a mismatch between the nutrient compositions of the diet and genetically determined nutritional requirements. The result is that contemporary diets generate diet-induced metabolic acidosis in contemporary Homo sapiens.
17. Wiederkebr, M. and Krapf, R. Metabolic and endocrine effects of metabolic acidosis in humans, Swiss Medical Weekly 2001:131, 127-132, 2001.