The Diet\'s Net Acid Load is, in part, responsible for the age-related loss of bone and skeletal muscle mass

1. The Role of the Diet’s Net Acid Load in Aging Pedro Carrera Bastos Sevilla October 25, 2009

3. Arterial blood PH Rose BD, Post TW. Clinical Physiology of Acid-base and Electrolyte Disorders . McGraw-Hill, 2001. pH = 7,62 + log HCO 3 - /PCO 2 (Henderson-Hasselbach) pH H+ (nanoeq/L) PCO2 mmHg HCO3- (mEq/L) Arterial blood 7,37-7,43 37-43 36-44 22-26

6. Net Endogenous Acid Production

8. Net Acid Load for some foods Net base yielding Net Acid yielding PRAL (mEq/100 kcal) NEUTRAL Frassetto L.A. et al. J Nephrol . 2006 Mar-Apr;19 Suppl 9:S33-40. PRAL (mEq/100 kcal) PRAL (mEq/100 kcal) Fish 14,6 Meat 12,4 Poultry 7,8 Egg 7,3 Shellfish 7,3 Cheese 3,3 Milk 1,3 Cereals 1,1 Nuts -1,1 Fruit -5,2 Tubers -5,4 Mushrooms -11,2 Root vegetables -17,1 Tomato -17,5 Vegetables -23,4 Legumes -0,4

10. Why is this relevant???

15. Pathophysiologic consequences of severe metabolic acidosis in humans

16. Chronic acidosis and bone health

21. Chronic acidosis and skeletal muscle nitrogen metabolism

23. Glutamine Acid Excretion Amonia (NH 4 ) > Urinary Acceptor of H+ Frassetto L, et al. Eur J Nutr . 2001 Oct;40(5):200-13

25. Other adverse consequences of Chronic Metabolic acidosis

28. Chronic low-grade diet-induced Metabolic Acidosis

31. Bone health

32. Neutralization of dietary acid load for 7 days in nine healthy subjects (6 men, 3 women) induced a significant cumulative calcium retention and significantly reduced the urinary excretion of deoxypyridinoline, pyridinoline, and n-telopeptide

33. Frassetto L, Morris RC Jr, Sebastian A. J Clin Endocrinol Metab . 2005 Feb;90(2):831-4. KBC treatment induced a dose-dependent decrease in UCaV/Cr that persisted up to 36 months, with the greatest decreases occurring in those women with the greatest baseline UCaV

34. The addition of oral potassium citrate to a high-salt diet prevented the increased excretion of urine calcium and the bone resorption marker caused by a high salt intake.

36. Lower estimates of energy-adjusted NEAP were correlated with greater spine and hip BMD and greater forearm bone mass

38. Children with a higher dietary PRAL had significantly less cortical area (P 0.05) and bone mineral content (P 0.01).

39. Low nutritional acid load was correlated with higher BMD at the heel in very elderly women with a fracture history

41. Fruit and vegetable intake may protect against premenopausal bone loss

42. High fruit and vegetable intakes have beneficial effects on the bone area of the radius and whole body in early pubertal girls . The lower urinary calcium output associated with higher fruit and vegetable intakes may be a modulating factor.

43. 12-y-old girls consuming high amounts of fruit had significantly higher heel BMD than did the moderate fruit consumers

44. Appropriate intakes of vegetables and fruit have a beneficial effect on TBBMC in boys aged 8–20 y

45. Higher fruit and vegetable intakes may have positive effects on bone mineral status in both younger and older age groups, especially at the spine and femoral neck.

46. Cola intake was associated with significantly lower BMD at each hip site , but not the spine, in women but not in men

47. Bicarbonate-rich alkali mineral waters with low potential renal acid load values were shown to decrease bone resorption markers and even parathyroid hormone levels

48. Jajoo R, et al. J Am Coll Nutr . 2006 Jun;25(3):224-30.

49. Skeletal muscle nitrogen metabolism

52. Higher excretion of potassium is associated with greater %LBM in healthy older men and women “ The positive association of potassium with %LBM may be related to the neutralizing effect of increased ingestion of potassium salts on the mild metabolic acidosis resulting from habitual ingestion of a typical net acid–producing American diet ”

53. Other consequences

54. Net Endogenous Acid Production was positively associated with excretions of magnesium and calcium

55. Potentially bioactive free glucocorticoids are metabolically affected by diet-dependent net endogenous acid production This elevation in cortisol can be attenuated when NEAP is neutralized via bicarbonate supplementation or a low net acid-yielding diet Maurer M, et al. Am J Physiol Renal Physiol 2003, 284:F32-40. Remer T, Pietrzik K, Manz F. J Clin Endocrinol Metab 1998, 83:2132-7.

57. Frassetto LA, et al. J Nutr . 2008 Feb;138(2):419S-422S

58. NEAP in pre-agricultural diets Sebastian A, et al. Am J Clin Nutr . 2002 Dec;76(6):1308-16 159 HG societies 87% NEAP <0

59. EDNP – Empty calories (oils, added fats & sugar) . Frassetto L.A. et al. J Nephrol . 2006 Mar-Apr;19 Suppl 9:S33-40

61. British Medical Association &quot;Compared with current diets, the pre-agricultural hunter-gatherer diets of our Palaeolithic ancestors were based on wild animal and plant foods and were much higher in protein and lower in carbohydrate &quot; &quot;Humans evolved to consume a diet very different from that consumed by many people today. This makes our physiology potentially mismatched to our contemporary lifestyles, increasing the risks of ill health .&quot; February 2009 Early life nutrition and lifelong health Hanson M, Fall C, Robinson S, Baird J. Early life nutrition and lifelong health , BMA, 2009 Feb

62. Thank you Special thanks to Prof. Loren Cordain , of Colorado State University

63. Pedro Carrera Bastos [email_address] www.nutriscience.pt