Effect of 50- and 100-mg vitamin E supplements on cellular immune function in noninstitutionalized elderly persons.
BACKGROUND
It has been suggested that vitamin E can counteract the age-associated decline in cellular immune responsiveness (CIR). Particularly, T helper cell type 1 (Th1) activity, ie, interferon (IFN) gamma-producing Th1 activity and, hence, delayed-type hypersensitivity (DTH) would be enhanced by vitamin E supplementation.


OBJECTIVE
Our aim was to study the effects of 6 mo supplementation with 50 and 100 mg vitamin E on CIR in the elderly.


METHODS
A double-blind, placebo-controlled trial was conducted in 161 healthy elderly subjects aged 65-80 y. CIR was measured in vivo by means of DTH skin tests and in vitro by assessing the production of interleukin (IL) 2, IFN-gamma (a typical Th1 cytokine), and IL-4 (a typical Th2 cytokine) by peripheral blood mononuclear cells after stimulation with phytohemagglutinin.


RESULTS
Both DTH and IL-2 production showed a trend toward increased responsiveness with increasing dose of vitamin E. However, IFN-gamma production decreased whereas IL-4 production increased in the groups receiving vitamin E. Only the change in the number of positive DTH reactions was borderline significantly larger in the 100-mg vitamin E group than in the placebo group (P = 0.06, Bonferroni adjusted). Subjects receiving 100 mg vitamin E with low baseline DTH reactivity or who were physically less active had a significantly larger increase in the cumulative diameter of the skin induration resulting from the DTH test than did the placebo group (P = 0.03), although this difference was not significant after Bonferroni correction (P = 0.07).


CONCLUSIONS
Possible beneficial effects of 100-mg vitamin E supplementation may be more pronounced in particular subgroups of elderly subjects.
Pallast
E G
EG
Division of Human Nutrition and Epidemiology and the Environmental and Occupational Health Group, Agricultural University Wageningen, The Netherlands.
Schouten
E G
EG
de Waart
F G
FG
Fonk
H C
HC
Doekes
G
G
von Blomberg
B M
BM
Kok
F J
FJ
D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D006968:Hypersensitivity, Delayed / Q000188:drug therapy*; D007111:Immunity, Cellular / Q000187:drug effects*; D007378:Interleukins / Q000096:biosynthesis; D008297:Male; D009426:Netherlands; D014810:Vitamin E / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*
D007378:Interleukins; D014810:Vitamin E