Lack Of Iron Lowers Immunity

Lack of Iron Lowers Immunity Older people tend to have reduced immunity to infection, and also decreased iron stores. There seems to be a link . . .

Introduction As people age, they tend to lose some of their resistance to infections, etc. This is because of a reduction in what are called their "T-cell mediated functions", or, as it's often put, their immunocompetence. And it seems likely that poor nutrition in the elderly can make this worse. One of the nutritional shortcomings that's common in homebound older people is iron deficiency. Can this be a factor in age-related reduction in immunocompetence? A study from Penn State reported in the American Journal of Clinical Nutrition indicates that this is indeed the case.

What was done Blood samples were taken from apparently healthy, homebound women over 60 who were receiving living assistance - e.g. Meals-on-Wheels. They gave a full medical history, to rule out any chronic medical conditions or infections and the use of medications that are known to affect the immune response. None of them took iron supplements. The volunteers' height and weight were recorded, and those with a body mass index (BMI) under 20 were excluded from the study. A full blood count, sedimentation rate, and clinical chemistry were done to ensure they had no serious disorder. The various forms of iron in the blood (serum ferritin, serum transferrin, serum iron, and ironbinding capacity), were measured, along with protein, vitamin B-12, folic acid and zinc, deficiencies of which may cause a lessened immune response. A whole battery of tests of immune function was done; the most relevant of these were the Tcell response to stimulation and the ability of white cells to phagocytose, or consume, bacteria.

What was found There were 61 women in the analysis; their average age was 76. Twelve of them were classified as iron-deficient, and 49 as iron-sufficient. There were no significant differences between these two groups with regard to BMI, serum protein, vitamin B-12, folic acid, plasma zinc, white cell count, and sedimentation rate. This suggests that none of these factors would interfere with the assessment of a possible link between iron-deficiency and reduced immunocompetence. The T-cell response to stimulation was significantly less in iron-deficient women than in their iron-sufficient counterparts. While phagocytosis did not differ significantly between the two groups, the 'respiratory burst' in this test (an indicator of bacteria-killing activity) was significantly less in the iron-deficient group.

What this means About one in five elderly homebound women were found to have iron deficiency, which amounted to anemia in half of them. And this iron-deficiency was linked to a significant reduction in their immune response to attack, so that they were at greater risk of developing an infection. The authors of this study say they are examining the benefits of iron supplements on immune function in iron-deficient older women. Until the results of this study are available, it would certainly make sense to ensure that older, homebound women (and men) aren't iron-deficient; and if they are, they should probably be treated with iron supplements, just in case.