Decline in old age, particularly in the "failure to thrive" syndrome, has prominent neuropsychosensory components. Evidence is increasing that nutritional factors, particularly micronutrients, can influence neural function, and hence may be a modifiable component of old age cognitive decline. Zinc and vitamin B12 are two important micronutrients, essential for central nervous system function. However, they are frequently inadequate in the diet of elder (based on the current Recommended Daily Allowances). Our recent pilot study in 98 elderly retired women, age 76 to 99, indicated that those with a combination of low serum zinc and low B12 had substantially lower Mini-Mental Status Examination scores when compared to those who had only one low level. The purpose of our proposed observational study is to prospectively examine the associations between the level of zinc, vitamin B12, cognitive decline, and aging. There are 678 women, age 76 to 103, in the study. To explore these relationships further, we propose an expanded four year, prospective, observational study of 760 women, age 76 to 103. We hypothesize that in elderly women: 1) low zinc and low B12 levels will each be related to an accelerated rate of cognitive decline, 2) the combination of low zinc and low B12 levels will be related to an exaggerated rate of cognitive decline (i.e., synergism), 3) certain groups are particularly vulnerable to the effects of low zinc and low B12 (those with low education, and those, specifically, with low pre-morbid cognitive ability) and 4) those who receive zinc and B12 supplements will have a slower rate of cognitive decline than comparable women who are not receiving supplements. These hypotheses will be tested in a population of women participating in an ongoing NIA-funded study (entitled "Independent and dependent life participating in an ongoing NIA-funded study (entitled "Independent and dependent life in the elderly". To test these hypotheses the SERCA applicant, will add a nutritional component to the ongoing NIA-funded study. This nutritional component will include clinical nutritional assessments and the collection of serum samples for the determination of zinc and B12 levels. These micronutrients will then be related to cognitive and functional decline (assessed by annual assessments in the ongoing NIA-funded study).