Diet
and your immune system
Like any fighting force, the immune system
army marches on its stomach. Healthy immune system warriors need good, regular
nourishment. Scientists have long recognized that people who are malnourished
are more vulnerable to infectious diseases. For example, researchers don't know
whether any particular dietary factors, such as processed foods or high simple
sugar intake, adversely affects immune function.
There is some experimental evidence that
various micronutrient deficiencies — for example, deficiencies of
zinc, selenium, iron, copper, folic acid, and vitamins A, B6, C,
and E — alter cellular immune responses. However, whether that translates to
changes in the human immune system and impacts on health remain unknown.
So, what can you do? If you suspect your diet is
not providing you with all your micronutrient needs — maybe, for instance, you
don't like vegetables — taking a daily multivitamin and mineral supplement may
bring other health benefits, beyond any possibly beneficial effects on the
immune system. Taking mega doses of a single vitamin does not. More is not
necessarily better.
Improve immunity with herbs and supplements?
Walk into a store, and you will find bottles
of pills and herbal preparations that claim to "support immunity" or
otherwise boost the health of your immune system. Although some preparations
have been found to alter some components of immune function, thus far there is
no evidence that they actually bolster immunity to the point where you are
better protected against infection and disease. Demonstrating whether an herb —
or any substance, for that matter — can enhance immunity is, as yet, a highly
complicated matter. Scientists don't know, for example, whether an herb that
seems to raise the levels of antibodies in the blood is actually doing anything
beneficial for overall immunity.