Iron reduction in blood donors

[jyb]

Iron deficiency in whole blood donors

Cable and colleagues1 note that cardioprotective health benefits of iron depletion have been proposed for blood donors.18 The iron-heart hypothesis is that “the greater incidence of heart diseases in men and postmenopausal women compared with the incidence in premenopausal women is due to higher levels of stored iron in these two groups.”

But

Overall, the majority of epidemiologic studies have found no significant association between the risk of cardiovascular disease and body iron stores.27–37 In particular, iron stores were not associated with the risk of coronary heart disease in women, whether pre- or post-menopausal.38 On balance, a decreased risk of heart disease with iron depletion is unproven,39–41 even if not disproven,42–46 by the evidence gathered over the past thirty years.

 

[Such_Saturation]

I know this one http://m.heart.bmj.com/content/78/2/188.short

One unit per year will half your ferritin levels.

 

[jyb]

Here's another one about iron stores varying with age: Association of age, sex, and race with body iron stores in adults: Analysis of NHANES III data

It has plots of mean serum ferritin versus age. On Fig 1, we that for men it reaches its peak quickly, at age 30-39. This supports Ray's claim in his Iron Danger's article. The amount almost triples from 17-19 to 30-39! However, for women it does not reach its peak before 60-69... Note that these are mean values but the individual differences are really huge.

We have documented different patterns for levels of
the serum ferritin by age for sex and race (Figures 1 and
2). Serum ferritin levels rose sharply during the late
teens in men and reached maximum in the 30- to 39-
year-old age group. Thereafter, levels plateaued until
approximately age 70 years, after which they declined.
This decline with aging may be caused by either a
decline in iron intake in later life or a selective disadvantage
for survival of higher ferritin values in men.
By contrast, ferritin levels remained relatively low in
women until menopause, after which they rose but not
to levels as high as in men of comparable age (Figure
1). Male/female differences were greater for blacks
than for whites and Hispanics (Figure 2).

I don't imagine people reducing iron intake at they age, so for my this supports the second hypothesis, that higher ferritin is a disadvantage. The study questions notes the huge increase of store compared to childhood is not necessarily a good thing:

There is no known physiologic
requirement for this increase in iron stores. Lower iron
stores characteristic of highly conditioned athletes and
blood donors are compatible with excellent health.41 A
clue that such iron accumulation may be inappropriate
is that accepted normal values for the ferritin level
include an upper limit that may be 30-fold greater than
the lower limit (300 vs 12 μg/L, respectively), a range
wider than for other physiologic parameters.42

Ferritin levels in the range of 15 to 50 μg/L may be optimal
physiologically, on the basis of data showing correlations
between serum ferritin levels >50 μg/L with
vascular disease risk,1