ABSTRACT: The number and proportion of senior citizens is increasing in affluent countries. Although many people remain
relatively healthy at high age, old age will sooner or later lead to a reduction of physiological function. The immune system and
intestinal tract are among those organs which activity is reduced. Research suggests that there is maybe a correlation between
the two. Specific pre- and/or probiotics have been shown to influence the composition of the intestinal microbiota. In some
cases, this seems to correlate with improvements in immune function in elderly. A causal relationship remains, however, to be
documented. Microbiota changes as such, usually increases in faecal levels of bifidobacteria, are no guarantee for improved
immune or other bodily functions.