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"If you're interested in personal health, public health, or you just want to read an amazing story, I highly recommend this book."

Dr. Eric Norman

Scientific References

1. van Asselt DZB, de Groot LCPGM, van Staveren WA, et al. Role of cobalamin intake and atrophic gastritis in mild cobalamin deficiency in older Dutch subjects. Am J Clin Nutr 1998;68: 328-34.
2. Carmel R, Green R, Jacobsen DW, et al. Serum cobalamin, homocysteine and methylmalonic acid levels in a multiethnic elderly population: ethnic and sex differences in cobalamin and metabolite abnormalities. Am J Clin Nutr 1999; 70: 904-10.
3. Williams Hematology, Fifth Edition, Editors: E. Beutler, M. Lichtman, B. Coller, and T. Kipps, 1995, p. 480, McGraw-Hill, Inc.
4. Kuzminski AM, Del Giacco EJ, Allen RH, et al. Effective treatment of cobalamin deficiency with oral cobalamin. Blood; 1998: 92:1191-98.
4A. Dharmarajan TS and Norkus EP. Approaches to vitamin B12 deficiency. Early treatment may prevent devastating complications. Postgraduate Medicine 2001; 110(1): 99-105.
5. Donaldson MS Metabloic Vitamin B12 Status on a Mostly Raw Vegan Diet with Follow-Up Using Tablets, Nutrtional Yeast, or Probiotic Supplements. Ann Nutr Metab 2000;44:229-234.
6. Carmel R. Current Concepts in Cobalamin Deficiency. Annu Rev Med 2000;51:357-375.
7. Duell PB and Malinow MR. Homocysteine: an important risk factor for atherosclerotic vascular disease. Current Opinion in Lipidology 1997; 8:28-34.
8. Norman EJ, Berry HK, Denton MD. Identification and quantitation of urinary dicarboxylic acids as their dicyclohexyl esters in disease states by gas chromatography mass spectrometry. Biomed Mass Spectrometry 1979; 6:546-53.
9. Norman EJ. Gas chromatography mass spectrometry screening of urinary methylmalonic acid: early detection of vitamin B12 (cobalamin) deficiency to prevent permanent neurologic disability. GC/MS News 1984; 12: 120-9.

GC-MS News was a Japanese Journal but is no longer in business. The original article, published in English in GC-MS News, can be downloaded by clicking here.
10. Norman EJ, Martelo OJ, Denton MD. Cobalamin (vitamin B12) deficiency detection by urinary methylmalonic acid quantitation. Blood 1982; 59: 1128-31.

11. Norman EJ, Martelo OJ, Denton. Methylmalonic acid excretion (Letter). Blood 1983; 61: 208-9.
12. Norman EJ ( Intr. By CJ Glueck). High incidence of neurologic disease in covert B12 (cobalamin) deficiency: early detection of cobalamin deficiency through urinary methylmalonic acid screening (abstract). Clin Res 1983; 31:686a.
13 Norman EJ. Vitamin B12 deficiency in the elderly ( letter). J AM Geriartr Soc 1985; 33: 374.
14. Norman EJ, Morrison JA. Screening elderly populations for cobalamin (vitamin B12) deficiency using the urinary methylmalonic acid assay by gas chromatography mass spectrometry. Am J Med 1993; 94: 589-594.
15. Norman EJ, Logan D, Terrell PF. Falsely high serum B12 levels (letter). Am J. Clin Pathol 1986; 86: 692 and 1987; 87: 154.
16. Norman EJ, Hunt TP. Leal MN, Morrison JA, Hensley CM. Screening a nursing home population for cobalamin (vitamin B12) deficiency through quantitation of urinary methylmalonic acid (MMA) ( abstract). Blood 1989; 74 Suppl.1.
17. Matchar DB, Feussner JR, Millington DS, et al. Isotope dilution assay for urinary methylmalonic acid in the diagnosis of vitamin B12 deficiency.
A prospective clinical evaluation. Ann Intern Med 1987; 106: 707-710.
18. Matchar DB, McCrory DC, Millington DS,
Feussner JR. Performance of the serum cobalamin assay for diagnosis of cobalamin deficiency. Am J Med Sci 1994; 308: 276-283.
19. Norman EJ. Urinary methylmalonic acid/creatinine ratio defines true tissue cobalamin deficiency. Br J Haematol (letter) 1998; 100: 614-615.
20. Crane MG, Register UD, Lukens RH, Gregory R. Cobalamin (CBL) studies on two total vegetarian (vegan) families. Vegetarian Nutr Int J 1998; 2/3: 87-92.
21. Norman EJ. Urinary methylmalonic acid/creatinine ratio: A gold standard test for tissue vitamin B12 deficiency. JAGS (letter) 1999; (47)9: 1158.
22. Lindenbaum J, Healton EB, Savage DG, et al. Neuropsychiatric disorders caused by cobalamin deficiency in the absence of anemia or macrocytosis. NEJM 1988; 318: 1720-1728.
23. Norman EJ, Denton MD, Martelo OJ, Flessa HC. Cobalamin deficiency and neuropsychiatric disorders. NEJM (letter) 1988; 319: 1733-4.
24. Roach ES, McLean WT. Neurologic disorders of vitamin B12 deficiency. Am Fam Physician 1982; 25: 111-115.
25. Martin DC, Francis J, Protetch J, Huff FT. Time dependency of cognitive recovery with cobalamin replacement: report of a pilot study. JAGS 1992; 40: 168-172.
26. Cooper BA, Fehedy V, Blanshay P. Recognition of deficiency of vitamin B12 using measurement of serum concentration. J Lab Clin Med 1986; 107:447--452.
27. Pennypacker LC, Allen RH, Kelly JP, et al. High prevalence of cobalamin deficiency in elderly outpatients. JAGS 1992; 40: 1197-1204.
28. Stabler SP. Screening the older population for cobalamin (vitamin B12) deficiency. JAGS 1995; 43:1290-1297.
29. Naurath HJ, Joosten E, Riezler R, Stabler SP, Allen RH, Lindebaum J. Effects of vitamin B12, folate, and vitamin B6 supplements in elderly people with normal serum vitamin concentrations. Lancet 1995; 346: 85-89.
30. Lindenbaum J, Rosenberg IH, Wilson PWF, Stabler SP, Allen RH. Prevalence of cobalamin deficiency in the Framingham elderly population. Am J Clin Nutr 1994; 60: 2-11.
31.Yao Y, Yao SL, Yao SS, Yao GY, Lou W. Prevalence of vitamin B12 deficiency among geriatric outpatients. J of Fam Prac 1992; 35: 524-528.
32. Goodman M, Chen XH, Darwish D. Are U.S. Lower Normal B12 Limits Too Low? JAGS 1996; 44: 1274-1275.
33. Norman EJ, Cronin C. Cobalamin deficiency. Neurology 1996; 47: 310-311.
34. Hvas AM, Juul S, Gerdes LU, Nexo E. The marker of cobalamin deficiency, plasma methylmalonic acid, correlates to plasma creatinine. J Int Med 2000; 247: 507-512.
35. Stabler SP, Marcell PD, Podell ED, et al. Elevation of total homocysteine in the serum of patients with cobalamin or folate deficiency detected by capillary gas chromatography mass spectrometry. J Clin Invest 1988; 81: 466-474.
36. Scalabrino G, Buccellato FR, Tredice G, Morabito A. Enhanced levels of biochemical markers of cobalamin deficiency in totally gastrectomized rats; uncoupling of the enhancement from the severity of spongy vacuolation in spinal cord. Experimental Neurology 1997; 144: 258-265.
37. Scalabrino G, Buccellato FR, Tredict G. Methylmalonic acid as a Marker for cobalamin deficiency: Fact of fantasy? Elucidaytio9ns form the cobalamin- deficient rat. Br J Haematology 1998; 100: 605-618.
38. Doscherholmen A, Swaim WR. Impaired assimilation of egg Co57 vitamin B12 in patients with hypochlorhydria and achlorhydria and after gastric resection. Gastroenterology. 1973; 64: 913-919.
39. Specker BL, Miller D, Norman EJ, Greene H, Hayes KC. Increased urinary methylmalonic acid excretion in breast-fed infants of vegetarian mothers and identification of an acceptable dietary source of vitamin B12. 1988; 47:89-92.
40. McCann MT, Thompson MM, Gueron IC, Lemieux B, Giguere R, Tuchman M. Methylmalonic acid quantification by stable isotope dilution gas chromatography-mass spectrometry from filter paper urine samples. 1996; 42:910-914.
41. Pruthi RK, Tefferi A. Pernicious anemia revisited. Mayo Clin Proc 1994;69:144-150.
42. Yamauchi H, Omine M, Tsukamoto N, et al. Urinary methylmalonic acid excretion and clinical features in megaloblastic anemia due to vitamin B12 deficiency. Jpn J Clin Hematol 1989; 30:835-839.
43. Anand A. Urinary methylmalonic acid and cobalamin deficiency in the elderly. Am J Med 1995; 98:514.
44. Rasmussen K, Studies on methylmalonic acid in humans. I. Concentration in serum and urinary excretion in normal subjects after feeding and during fasting, and after loading with protein, fat, sugar, isoleucine, and valine. Clin Chem 1989; 35:2271-6.
45. THE VITAMIN B12 REPORT. Published by Norman Clinical Laboratory, Inc.(NCL), Editor: EJ Norman. Introductory Issue, Spring 1987; Vol. 1(2), Fall, 1987; Vol. 2(1), Feb, 1988; Vol. 2(2), June, 1988; Vol. 3(1), Dec. 1989; Vol. 4(1), July, 1992. For copies of any issue, please contact NCL.
46. Krasinski SD, Russell RM, Samloff IM, et al. Fundic atrophic gastritis in an elderly population. JAGS 1986; 34: 800-806.
47. Baik HW and Russell RM. Vitamin B12 deficiency in the Elderly. Annu Rev
Nutr 1999; 19:357-77.
47A. van Dusseldorp V, Schneede J, Refsum H, Ueland PM, Thomas CMG, de Boer E and van Staveren WA. Risk of persistent cobalamin deficiency in adolescents fed a macrobiotic diet in early life. Am J Clin Nutr; 1999: 69: 664-71.
47B. Graham SM, Arvela OM and Wise GA. Long-term neurologic consequences of nutritional vitamin B12 deficiency in infants. J Pediatr 1992; 121: 710-4.
48. Stabler SP, Allen RH, Fried LP, Pahor M, Kittner SJ, Penninx BWJH and Guralnik JM. Racial differences in prevalence of cobalamin and folate deficiencies in disabled elderly women. Am J Clin Nutr 1999; 70:911-19.
49. Howard JM, Azen C, Jacobsen DW, Green R and Carmel R. Dietary intake of cobalamin in elderly people who have abnormal serum cobalamin, methylmalonic acid and homocysteine levels. 1998; 52: 582-587.
49A. Norkus EP, Patel B and Dharmarajan TS. Does Regular Multivitamin (MVT) use prevent vitamin B12 deficiency in community elderly? (Abstract) J Am Coll Nutr 1999; 18:535.
49B. Crane MG, Sample C, Patchett S, and Register UD. Vitamin B12 studies in total vegetarians (vegans). J Nutr Med 1994; 4:419-30.
49C. Kondo H, Binder MJ, Kolhouse JF, Smythe WR, Podell ER, and Allen RH. Presence of and formation of CBL analogues in multivitamin-mineral pills. J Clin Invest; 1982: 70: 889-98.
49D. Tucker KL, Rich S, Rosenberg I, Jacques P, Dallal G, Wilson PWF, and Selhub J. Plasma vitamin B12 concentrations relate to intake source in the Framingham Offspring Study. Am J Clin Nutr 2000; 71: 514-22.
49E. Wynn M and Wynn A. The Danger of B12 deficiency in the elderly. Nutritioin and Health 1998;12: 215-226.
50. Klee GG. Cobalamin and Folate Evaluation: Measurement of Methylmalonic Acid and Homocysteine vs. Vitamin B12 and Folate. Clin Chem 2000; 46:1277-1283.
51. Honein MA, Paulozzi LJ, Mathews TJ, Erickson JD, Wong LC. Impact of Folic Acid Fortification of the US Food Supply on the Occurrence of Neural Tube Defects. JAMA 2001; 285: 2981-2986.
52. Mills JL and England L. Food Fortification to Prevent Neural Tube Defects. Is it working? (Editorial) JAMA 2001; 285: 3022-3.
53. Stabler SP, Lindenbaum and Allen RH. Vitamin B12 deficiency in the elderly: current dilemmas. Am J Clin Nutr 1997; 66:741-9.
54. Norman EJ (Intr. by Franco RS). Cobalamin (vitamin B12) Deficiency
Identified in Young, Caucasian women. Blood 2000; 96(11):8b.
55. Herbert V and Bigaouette J. Call for endorsement of a petition to the Food and Drug Administration to always add vitamin B12 to any folate fortification or supplement. Am J Clin Nutr 1997; 65: :572-3.
56. Carmel R. Prevalence of undiagnosed pernicious anemia in the elderly. Arch Intern med 1996; 156:1097-1100.
57. Catterall P, DelPonte P. Independences for older Americans: real answer to health aging. Alliance for Aging Research 1992; June.
58. Bouvier L, DeVita C. The baby boom--entering midlife. Population Reference Bureau 1991, Nov.
59. Ernst RL, Hay JW. The U.S. economic and social costs of Alzheimer's disease revisited. Am Public Health 1994; 84:1261-1264.
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62. Alzheimer's Disease: Unraveling the Mystery, National Institute on Aging, NIH,
63. Wang HX, Wahlin A, Basun H, Fastbom J, Winblad B, Fratiglioni L. Vitamin B12 and folate in relation to the development of Alzheimer's disease. Neurology 2001; 56: 1188-1194.
64. Seshadri S, Beiser A, Selhub J, et al. Plasma Homocysteine as a Risk Factor for Dementia and Alzheimer's Disease. NEJM 2002; 346(7): 476-483.
65. Hung C, Huang P, Lu S et al. Plasma Homocysteine Levels in Taiwanese Vegetarian Are Higher than Those of Omnivores. J Nutr 2002; 132: 152-158.
66. Vitamin Void. Heart disease may lurk in B12 deficiency. Science News 2002; 161(7): 101-2.
67. Halliday AW, Vukelja SJ. Neurologic manifestations of vitamin B12 deficiency in a military hospital. Military Med 1991; 156: 201-204.
68. Carmel R. Subtle cobalamin deficiency. Ann Int Med 1996; 124(3): 338-339.
69. Swain R. An update of vitamin B12 metabolism and deficiency states. J Fam Prac 1995; 41(6): 595-600.
70. Eggersten R, Nilsson T, Lindstedt G, Lundberg P. Prevalence and diagnosis of cobalamin deficiency in older people. JAGS 1996; 44:1273-4.
71. Wieland RG. Vitamin B12 deficiency in the nonanemic elderly. JAGS 1986; 34:618.
72. Panke TW. Editorial: Neurologic Damage From Vitamin B12 Deficiency Despite Normal B12 Level. Pathologist Newsletter, Good Samaritan Hosp., Cincinnati, OH 1994; 12(1).
73. Murray MT, Encyclopedia of Nutritional Supplements 1996; Prima Health: Chapter 15.

For test kit requests or more information
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Call toll free at 1-800-397-7408

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