When it comes to the pH and net acid load in the human diet, there has been considerable change from the hunter gather civilization to the present [5]. With the agricultural revolution (last 10,000 years) and even more recently with industrialization (last 200 years), there has been an decrease in potassium (K) compared to sodium (Na) and an increase in chloride compared to bicarbonate found in the diet [6]. The ratio of potassium to sodium has reversed, K/Na previously was 10 to 1 whereas the modern diet has a ratio of 1 to 3 [7]. It is generally accepted that agricultural humans today have a diet poor in magnesium and potassium as well as fiber and rich in saturated fat, simple sugars, sodium, and chloride as compared to the preagricultural period [6]. This results in a diet that may induce metabolic acidosis which is mismatched to the genetically determined nutritional requirements [8].

With aging, there is a gradual loss of renal acid-base regulatory function and a resultant increase in diet-induced metabolic acidosis while on the modern diet [9]. A low-carbohydrate high-protein diet with its increased acid load results in very little change in blood chemistry, and pH, but results in many changes in urinary chemistry. Urinary magnesium levels, urinary citrate and pH are decreased, urinary calcium, undissociated uric acid, and phosphate are increased. All of these result in an increased risk for kidney stones [10].

Much has been written in the lay literature as well as many online sites expounding on the benefits of the alkaline diet. This paper is an attempt to balance the evidence that is found in the scientific literature.

Georgina Cyr offers Plant Based Nutritional Coaching. Book your appointment today at Naturally Healthy Clinic 250-755-4051 reception@n-h-clinic.ca

 Conclusion

Alkaline diets result in a more alkaline urine pH and may result in reduced calcium in the urine, however, as seen in some recent reports, this may not reflect total calcium balance because of other buffers such as phosphate. There is no substantial evidence that this improves bone health or protects from osteoporosis. However, alkaline diets may result in a number of health benefits as outlined below

  1. Increased fruits and vegetables in an alkaline diet would improve the K/Na ratio and may benefit bone health, reduce muscle wasting, as well as mitigate other chronic diseases such as hypertension and strokes.
  2. The resultant increase in growth hormone with an alkaline diet may improve many outcomes from cardiovascular health to memory and cognition.
  3. An increase in intracellular magnesium, which is required for the function of many enzyme systems, is another added benefit of the alkaline diet. Available magnesium, which is required to activate vitamin D, would result in numerous added benefits in the vitamin D apocrine/exocrine systems.
  4. Alkalinity may result in added benefit for some chemotherapeutic agents that require a higher pH.

From the evidence outlined above, it would be prudent to consider an alkaline diet to reduce morbidity and mortality of chronic disease that are plaguing our aging population. One of the first considerations in an alkaline diet, which includes more fruits and vegetables, is to know what type of soil they were grown in since this may significantly influence the mineral content. At this time, there are limited scientific studies in this area, and many more studies are indicated in regards to muscle effects, growth hormone, and interaction with vitamin D.

References

1. Waugh A, Grant A. Anatomy and Physiology in Health and Illness. 10th edition. Philadelphia, Pa, USA: Churchill Livingstone Elsevier; 2007.
2. University, Birmingham oAa. Oceans reveal further impacts of climate change. ScienceDaily, 2010.
3. Hoegh-Guldberg O, Mumby PJ, Hooten AJ, et al. Coral reefs under rapid climate change and ocean acidification. Science2007;318(5857):1737–1742. [PubMed]
4. Dam-ampai SO J, Nilnond C. Effect of cattle manure and dolomite on soil properties and plant growth in acid upland soils. Songklanakarin Journal of Science and Technologh2005;27(supplement 3):727–737.
5. Ströhle A, Hahn A, Sebastian A. Estimation of the diet-dependent net acid load in 229 worldwide historically studied hunter-gatherer societies. American Journal of Clinical Nutrition2010;91(2):406–412.[PubMed]
6. Sebastian A, Frassetto LA, Sellmeyer DE, Merriam RL, Morris RC., Jr. Estimation of the net acid load of the diet of ancestral preagricultural Homo sapiens and their hominid ancestors. American Journal of Clinical Nutrition2002;76(6):1308–1316. [PubMed]
7. Frassetto L, Morris, Jr. R.C. RC, Jr., Sellmeyer DE, Todd K, 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 Nutrition2001;40(5):200–213. [PubMed]
8. Konner M, Boyd Eaton S. Paleolithic nutrition: twenty-five years later. Nutrition in Clinical Practice2010;25(6):594–602. [PubMed]
9. Lindeman RD, Goldman R. Anatomic and physiologic age changes in the kidney. Experimental Gerontology1986;21(4-5):379–406. [PubMed]
10. Reddy ST, Wang CY, Sakhaee K, Brinkley L, Pak CY. Effect of low-carbohydrate high-protein diets on acid-base balance, stone-forming propensity, and calcium metabolism. American Journal of Kidney Diseases2002;40(2):265–274. [PubMed]
11. Malov YS, Kulikov AN. Bicarbonate deficiency and duodenal ulcer. Terapevticheskii Arkhiv1998;70(2):28–32. [PubMed]
12. Ohman H, Vahlquist A. In vivo studies concerning a pH gradient in human stratum corneum and upper epidermis. Acta Dermato-Venereologica1994;74(5):375–379. [PubMed]
13. Ferris DG, Francis SL, Dickman ED, Miler-Miles K, Waller JL, McClendon N. Variability of vaginal pH determination by patients and clinicians. Journal of the American Board of Family Medicine2006;19(4):368–373. [PubMed]
14. Remer T, Manz F. Estimation of the renal net acid excretion by adults consuming diets containing variable amounts of protein. American Journal of Clinical Nutrition1994;59(6):1356–1361. [PubMed]
15. Remer T. Influence of diet on acid-base balance. Seminars in Dialysis2000;13(4):221–226. [PubMed]
16. Fenton TR, Eliasziw M, Tough SC, Lyon AW, Brown JP, Hanley DA. Low urine pH and acid excretion do not predict bone fractures or the loss of bone mineral density: a prospective cohort study. BMC Musculoskeletal Disorders2010;11, article 88 [PMC free article] [PubMed]
17. Boelsma E, van de Vijver LPL, Goldbohm RA, Klöpping-Ketelaars IAA, Hendriks HFJ, Roza L. Human skin condition and its associations with nutrient concentrations in serum and diet. American Journal of Clinical Nutrition2003;77(2):348–355. [PubMed]
18. Ince BA, Anderson EJ, Neer RM. Lowering dietary protein to U.S. recommended dietary allowance levels reduces urinary calcium excretion and bone resorption in young women. Journal of Clinical Endocrinology and Metabolism2004;89(8):3801–3807. [PubMed]
19. Boron WF. Regulation of intracellular pH. Advances in Physiology Education2004;28:160–179.[PubMed]
20. Remer T, Manz F. Potential renal acid load of foods and its influence on urine pH. Journal of the American Dietetic Association1995;95(7):791–797. [PubMed]
21. Fenton TR, Eliasziw M, Lyon AW, Tough SC, Hanley DA. Meta-analysis of the quantity of calcium excretion associated with the net acid excretion of the modern diet under the acid-ash diet hypothesis. American Journal of Clinical Nutrition2008;88(4):1159–1166. [PubMed]
22. Sebastian A, Morris RC., Jr. Improved mineral balance and skeletal metabolism in postmenopausal women treated with potassium bicarbonate. New England Journal of Medicine1994;331(4):p. 279.[PubMed]
23. Dawson-Hughes B, Harris SS, Palermo NJ, Castaneda-Sceppa C, Rasmussen HM, Dallal GE. Treatment with potassium bicarbonate lowers calcium excretion and bone resorption in older men and women. Journal of Clinical Endocrinology and Metabolism2009;94(1):96–102. [PMC free article][PubMed]
24. Heaney RP, Dowell MS, Hale CA, Bendich A. Calcium absorption varies within the reference range for serum 25-hydroxyvitamin D. Journal of the American College of Nutrition2003;22(2):142–146.[PubMed]
25. Schwalfenberg GK, Genuis SJ, Hiltz MN. Addressing vitamin D deficiency in Canada: a public health innovation whose time has come. Public Health2010;124(6):350–359. [PubMed]
26. Lu KC, Lin SH, Yu FC, Chyr SH, Shieh SD. Influence of metabolic acidosis on serum 1,25(OH)2D3 levels in chronic renal failure. Mineral and Electrolyte Metabolism1995;21(6):398–402. [PubMed]
27. Fenton TR, Lyon AW, Eliasziw M, Tough SC, Hanley DA. Phosphate decreases urine calcium and increases calcium balance: a meta-analysis of the osteoporosis acid-ash diet hypothesis. Nutrition Journal2009;8, article 41 [PMC free article] [PubMed]
28. Hulley SB, Vogel JM, Donaldson CL, Bayers JH, Friedman RJ, Rosen SN. The effect of supplemental oral phosphate on the bone mineral changes during prolonged bed rest. Journal of Clinical Investigation1971;50(12):2506–2518. [PMC free article] [PubMed]
29. Fenton TR, Lyon AW, Eliasziw M, Tough SC, Hanley DA. Meta-analysis of the effect of the acid-ash hypothesis of osteoporosis on calcium balance. Journal of Bone and Mineral Research2009;24(11):1835–1840. [PubMed]
30. Supplee JD, Duncan GE, Bruemmer B, Goldberg J, Wen Y, Henderson JA. Soda intake and osteoporosis risk in postmenopausal American-Indian women. Public Health Nutrition2011:1–7.[PMC free article] [PubMed]
31. Fenton TR, Tough SC, Lyon AW, Eliasziw M, Hanley DA. Causal assessment of dietary acid load and bone disease: a systematic review & meta-analysis applying Hill’s epidemiologic criteria for causality. Nutrition Journal2011;10(1, article 41) [PMC free article] [PubMed]
32. Frassetto LA, Morris RC, Jr., Sebastian A. Dietary sodium chloride intake independently predicts the degree of hyperchloremic metabolic acidosis in healthy humans consuming a net acid-producing diet. American Journal of Physiology—Renal Physiology2007;293(2):F521–F525. [PubMed]
33. Frings-Meuthen P, Buehlmeier J, Baecker N, et al. High sodium chloride intake exacerbates immobilization-induced bone resorption and protein losses. Journal of Applied Physiology2011;111(2):537–542. [PubMed]
34. Cappuccio FP, Meilahn E, Zmuda JM, Cauley JA. High blood pressure and bone-mineral loss in elderly white women: a prospective study. Lancet1999;354(9183):971–975. [PubMed]
35. Devine A, Criddle RA, Dick IM, Kerr DA, Prince RL. A longitudinal study of the effect of sodium and calcium intakes on regional bone density in postmenopausal women. American Journal of Clinical Nutrition1995;62(4):740–745. [PubMed]
36. Morris RC, Jr., Schmidlin O, Frassetto LA, Sebastian A. Relationship and interaction between sodium and potassium. Journal of the American College of Nutrition2006;25(3):262S–270S. [PubMed]
37. Barzel US, Massey LK. Excess dietary protein may can adversely affect bone. Journal of Nutrition1998;128(6):1051–1053. [PubMed]
38. Heaney RP, Layman DK. Amount and type of protein influences bone health. American Journal of Clinical Nutrition2008;87(5):156S–157S. [PubMed]
39. Dawson-Hughes B, Harris SS, Ceglia L. Alkaline diets favor lean tissue mass in older adults. American Journal of Clinical Nutrition2008;87(3):662–665. [PMC free article] [PubMed]
40. Garibotto G, Russo R, Sofia A, et al. Muscle protein turnover in chronic renal failure patients with metabolic acidosis or normal acid-base balance. Mineral and Electrolyte Metabolism1996;22(1–3):58–61.[PubMed]
41. Caso G, Garlick PJ. Control of muscle protein kinetics by acid-base balance. Current Opinion in Clinical Nutrition and Metabolic Care2005;8(1):73–76. [PubMed]
42. Webster MJ, Webster MN, Crawford RE, Gladden LB. Effect of sodium bicarbonate ingestion on exhaustive resistance exercise performance. Medicine and Science in Sports and Exercise1993;25(8):960–965. [PubMed]
43. McSherry E, Morris RC., Jr. Attainment and maintenance of normal stature with alkali therapy in infants and children with classic renal tubular acidosis. Journal of Clinical Investigation1978;61(2):509–527. [PMC free article] [PubMed]
44. Frassetto L, Morris RC, Jr., Sebastian A. Potassium bicarbonate reduces urinary nitrogen excretion in postmenopausal women. Journal of Clinical Endocrinology and Metabolism1997;82(1):254–259.[PubMed]
45. Wass JAH, Reddy R. Growth hormone and memory. Journal of Endocrinology2010;207(2):125–126.[PubMed]
46. Frassetto L, Morris RC, Jr., Sebastian A. Long-term persistence of the urine calcium-lowering effect of potassium bicarbonate in postmenopausal women. Journal of Clinical Endocrinology and Metabolism2005;90(2):831–834. [PubMed]
47. Vormann J, Worlitschek M, Goedecke T, Silver B. Supplementation with alkaline minerals reduces symptoms in patients with chronic low back pain. Journal of Trace Elements in Medicine and Biology2001;15(2-3):179–183. [PubMed]
48. Zofková I, Kancheva RL. The relationship between magnesium and calciotropic hormones. Magnesium Research1995;8(1):77–84. [PubMed]
49. Schwalfenberg G. Improvement of chronic back pain or failed back surgery with vitamin D repletion: a case series. Journal of the American Board of Family Medicine2009;22(1):69–74. [PubMed]
50. Groos E, Walker L, Masters JR. Intravesical chemotherapy. Studies on the relationship between pH and cytotoxicity. Cancer1986;58(6):1199–1203. [PubMed]
51. Smith SR, Martin PA, Edwards RHT. Tumour pH and response to chemotherapy: an in vivo 31P magnetic resonance spectroscopy study in non-Hodgkin’s lymphoma. British Journal of Radiology1991;64(766):923–928. [PubMed]
52. Raghunand N, Gillies RJ. pH and chemotherapy. Novartis Foundation Symposium2001;240:199–211.[PubMed]
53. Raghunand N, He X, Van Sluis R, et al. Enhancement of chemotherapy by manipulation of tumour pH. British Journal of Cancer1999;80(7):1005–1011. [PMC free article] [PubMed]
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