White blood cells, or leukocytes, are an essential component of the immune system, fighting infection and disease and helping the body heal from such damage when it arises. Besides indicating a potentially weakened immune system, low white blood cell, levels could also be the result of certain medications, bone marrow conditions or autoimmune disorders. One way vitamins and minerals can help with a low white blood cell count is by helping the body increase or better assimilate leukocytes. Another way is by providing additional support for the immune system, which in turn can help ameliorate the vulnerability a low white blood cell count may produce.
Low vitamin B6 levels have been associated with a weakened immune system and low levels of an important type of white blood cell known as lymphocytes. According to the Linus Pauling Institute at Oregon State University, in the early 1990s researchers discovered that vitamin B6 supplementation not only alleviated vitamin B6 deficiency but restored normalized lymphocyte proliferation as well. Part of the mechanism for this activity is that vitamin B6 supports the health of the organs that make the white blood cells, specifically the lymph nodes, thymus and spleen, or the lyphoid organs. The "Gale Encyclopedia of Cancer" reports that deficiencies of two other B vitamins, B12 and folate, or folic acid, may cause lowered white blood cell production.
There's a reason vitamin C has been a go-to staple of home cold remedies since time immemorial. Vitamin C is a powerful immune-booster, that works in large part by stimulating white blood cell production and function. The Linus Pauling Institute cites several studies verifying this fact, most of them conducted in the late 1970s and early 1980s.
Vitamin A, vitamin C and vitamin E are all powerful antioxidants that can help strengthen the immune system and provide support that may be much needed when the body's white blood cell levels are low. The minerals selenium, copper and zinc are also antioxidants. According to the book "Oxidative Damage to Nucleic Acids," antioxidants have shown in several studies to prevent oxidative damage to leukocytes, thereby improving leukocyte function and helping maintain adequate leukocyte levels.
The Linus Pauling Institute cites a 1995 study on the effects of low levels of copper on the body's immunity as finding, among its conclusions, that a copper deficiency could reduce production of a type of white blood cell known as neutrophils. This suggests that restoring normal copper levels in the blood could normalize white blood cell production as well. Long-term intake of high copper levels, however, has also been associated with immune system impairment.