Nutrition and Immune Function in the Elderly

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Quite a few interesting points are made in this abstract, imo:

" Effect of micronutrient status on natural killer cell immune

function in healthy free-living subjects aged >/=90 y. "

Ravaglia G, Forti P, Maioli F, Bastagli L, Facchini A, ni E,

Savarino L, Sassi S, Cucinotta D, Lenaz G.

Department of Internal Medicine, Cardioangiology, and Hepatology, the

Department of Angiology and Blood Coagulation, and the Division of

Geriatric Medicine, University Hospital Sant'Orsola-Malpighi,

Bologna, Italy. ravaglia@...

" BACKGROUND: Natural killer (NK) cells play a role in natural

immunity against tumor and infected cells. Advanced aging is

associated with functional impairment of NK cells and increased

susceptibility to nutritional deficiencies. OBJECTIVE: Our objective

was to test whether micronutrient status affects NK cell activity in

an older population. DESIGN: The relations between NK cell variables

(percentage of leukocytes and cytotoxicity) and blood concentrations

of selected micronutrients were studied in 62 healthy, free-living

northern Italian subjects (25 men, 37 women) aged 90-106 y.

Anthropometric measurements were also made. RESULTS: All subjects

were well nourished according to age-specific anthropometric norms

but many of them had micronutrient deficiencies. The prevalence of

micronutrient deficiency was highest for selenium (in approximately

50% of both sexes), zinc (in 52% of men and 41% of women), and

vitamin B-6 (in 40% of men and 59% of women), followed by vitamin A

(in 16% of men and 27% of women) and vitamin E, vitamin B-12, and

folate (each in <10% of both sexes). Ubiquinone-10 status was

inadequate in 40% of women and 24% of men (P = 0.02). The percentage

of NK cells was associated with serum zinc (men: r = 0.573, P = 0.

007; women: r = 0.373, P = 0.031) and selenium (women: r = 0.409, P =

0.018) concentrations. In women only, NK cell cytotoxicity at

different effector-target cell ratios was positively associated with

plasma vitamin E and ubiquinone-10 concentrations (P < 0.05). No

significant associations with NK cell variables were found for the

other measured nutrients. CONCLUSIONS: The results of this study

strengthen the hypothesis that individual micronutrients may affect

the number and function of NK cells in old age. The study also

confirms the high prevalence of micronutrient deficiencies in healthy

and apparently well-nourished persons aged >/=90 y. "

PMID: 10648276

Rodney.