Losing your memory as you age? Don't forget the value of folate

Numerous studies suggest that, in addition to its confirmed impact on cardiovascular risk, elevated plasma homocysteine (tHcy) is also implicated in the pathogenesis of Alzheimer's disease (AD).1 For example, a study in Boston has demonstrated that elevated plasma tHcy concentrations are associated with reduced spatial copying skills in 68 subjects 58 years and older.2 Likewise, elevated plasma tHcy was significantly associated with lower Cambridge Cognitive Examination scores in 30 elderly (@!65 y) people with clinically diagnosed AD.3 And, in a small group of elderly hospitalized patients with acute depression, reduced cognitive function was noted for those with higher tHcy.4

Most telling of all, in their casecontrol study comparing 164 clinically diagnosed AD patients 55 years and older to 108 controls of similar age, Clarke and colleagues found that elevated plasma tHcy, as well as low folate and vitamin B^sub 12^ levels, were common in patients with AD.5 Post_ mortem histologic analysis confirmed the diagnosis of AD in 76 of these patients. In that subset, the differences in all the foregoing parameters were even more significant than those observed in the larger AD-diagnosed cohort5 - not surprising since AD carries a misdiagnosis rate of 20% to 30%.6 Since cognitive assessments can be subjective,6 it's especially significant that in a follow-up three years later, physical manifestations of the disease (i.e., greater thickness of the medial lobe measured by x-ray cranial computed tomography) confirmed the initial, clinically observed link between AD and hyperhomocysteinemia and its affiliated nutritive deficiencies.5

References: 1. Graham IM et al. 1997. Plasma homocysteine as a risk factor for vascular disease. The Europeajn Concerted Action Project. JAMA 2278-1775-1781. 2. Riggs KM et al. 1996. Relations of vitamin beta^sub 12^, vitamin beta^sub 6^, folate, and homocystein to cognitive function in the Normative Aging Studyu. Am J Clin Nutr 63:306-314. 3. MacCaddon A et al. 1996. Total serum homocysteine in senile dementia of the Alzheimer's type. Int J Geriatr Psychiatry 31 235-239. 4. Bell IR et al. 1992. Plasma homocysteine in vascular disease and in nonvascular dementia of depressed elderly people. Acct Psychiatr Scand 86:386-390. 5. Clarke R et al. 1998. Folate, vitamin B^sub 12^, and serum total homocysteine levels in confirmed Alzheimer's Disease. Arch Neurol 55:1407-1408. 6. Miller JW. 1909.

Homocysteine and Alzheimer's disease. Nutr Reviews 57:126-129. 87. Jennes R. 1998. Composition of milk. In Fundamentals of Diary Chemistry. NP Wong et al (eds.) p 18. Van Nostrand Reinhold CO., NY. 8. Hagemeister H et al. 1990. Nitrogen balance in the human and effects of milk constituents. Bull Int Diary Federation 253:3-18. 9 Etherton TD. 1994. The Efficacy, Safety and Benefits of Bovine Somatropin and Porcine Somatotropin. American Council on Science and Health, In. NY, NY. 10. Food and Drug Administration, USDHHS. 1993. Animal drugs, feeds, and related products; sterile sometribove zinc suspension. Fed Regist. 58(2178);59946-59947. 11. Ball RO. 1989. Safety of the meat supply; facts vs fiction. Meat Probe 6:1-3.

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