You are what you eat. Following that logic too far would suggest that I am a vegetarian because I eat vegetarian animals. However, as we all know, our diet does have a profound effect on our health. But how does it affect our immune systems?

First of all, most people in developed countries are not vitamin deficient. One exception to this rule is the elderly, especially single old men living alone whose idea of cooking is nuking the physical remains of yesterdays’ big mac. Another exception is iron in women of child-bearing age who lose a significant amount of this important nutrient every month due to menstration. With these exceptions in mind, most of us in developed countries get enough of almost all the good things by eating a balanced diet. And taking vitamins won’t generally help people who already have enough. An important division among vitamins, however, is between fat soluble and non fat soluble because those that are fat soluble are stored but others are not. Therefore, we need to consume non fat soluble vitamins such as vitamin C more often.

Given the fact that most of us are not deficient in most vitamins and nutrients, deficiencies in all of the following have been shown to weaken the immune system: vitamins A, B complex, C and E; Iron, protein, copper, chromium, selenium and zinc. However, it is also true that over-doses of some of these can actually suppress the immune system and cause other problems, especially fat soluble vitamins which can build up to toxic levels in some cases. Speaking of too much not being good, one of my own studies showed that too much copper (although not fat soluble) in the diet could block the enhancement of the immune system by increased chromium in the diet. The golden mean applies here. If you are in doubt as to whether you are getting too little or too much of any given nutrient, consult the recommended daily allowances published by the Food and Drug Administration (FDA).

It is hard to overdose with vitamin C since it is water soluble. It has also been shown that although this vitamin does not cure the common cold, it can, in proper doses, reduce the severity of the illness. It appears that one of the ways it might do so is by enhancing the function of certain white blood cells (leukocytes). However, even in this case, nutritionists recommend that people never take more than 1,000 milligrams per day of vitamin C since extreme amounts can cause gastrointestinal discomfort, nausea and a sudden fondness for rap music (just kidding about the rap music). It is interesting that smokers may require more vitamin C than non-smokers since they require more repair of damaged lung tissues by leukocytes.

If you want more information about the relationship between diet and immunity, I would recommend you try the PDR health web site: ( http://www.pdrhealth.com/content/nutrition_health ).

So what is the bottom line? Look at labels and other indicators of vitamins and nutrients in your diet and consult the FDA recommended levels. If you think, you might not be getting enough of any of the nutrients listed above, try a vitamin supplement or multivitamin. As long as you don’t overdose (and you won’t if you follow the FDA guidelines), you have nothing to lose but some pocket change. However, the best advice is still what your mother probably told you – eat a balanced diet that includes a varierty of fresh fruits and vegetables and you will be helping your immune system stay strong.

This entry was posted on Monday, May 9th, 2005 at 8:09 am and is filed under Caring for the Immune System. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.