The promotion of blood donation is invariably approached from the angle of altruism. Promotional strategies emphasize the need for 38,000 pints of blood every day in the US—a pint almost every 2 seconds—for the regular and emergency treatment of a range of individuals, from cancer patients to burn victims to premature infants (who are in all probability thoroughly adorable).

But what if you're cruel, selfish and uncaring by nature? It turns out there might be some good reasons for you to donate too.

The most common reasons to be found in the research are predicated on excess iron storage. Iron is requisite to human and most non-human life on the planet. In the body, iron's primary function is aiding the transport of oxygen by red blood cells as hemoglobin, but it also plays a number of other roles, including assisting in the synthesis of DNA, collagen, and other protein structures. At the same time, iron poses serious risks to life as a potent pro-oxidant. Because of this, the treatment of iron by the body is remarkably careful: the absorption, distribution and storage of iron is reliant on a well integrated system of protein structures that prevent iron's direct exposure to the rest of the body.


Iron Absorption & Storage

There are two types of dietary iron: heme and non-heme. Heme iron is the form found in meat and is the more efficiently absorbed type (15% - 35%). Non-heme is found in plant foods and is less easily absorbed (2% - 20%), although its absorption rate is more greatly influenced by accompanying dietary factors. Meat, vitamin C and fructose all enhance the absorption of non-heme iron, while soy, calcium, phytates (nutrient-binding protein found in grains) and tannins and polyphenols (both found in tea) reduce its absorption.

When dietary iron enters the guts, it is taken up into enterocytes, epithelial cells lining the walls of the intestine. If systemic iron levels are low enough to require uptake, the iron is encased by the transferrin molecule and distributed through the body as appropriate. Otherwise the iron remains in the enterocytes, which regularly die and pass from the body, bringing the unabsorbed iron along. Average daily iron loss though mechanisms such as sweating, urination, and the regular sloughing of integumentary components is around 0.9 mg (pre-menopausal women may lose an additional 15-20 mg per month through menstruation). These losses are easily covered by anything that remotely resembles a decent diet.

So in theory, this combination of controlled absorption and regular dietary replenishment should maintain ideal iron levels in the body. Unfortunately it's not a flawless system, particularly when challenged by unnatural modern factors.

Nearly all grain foods in the US are fortified with easily absorbable iron. Many people take daily multivitamin/mineral supplements with sometimes enormous amounts of iron. High-fructose corn syrup is used to sweeten nearly every packaged food in addition to soda. In short, there is an epic assortment of variables that can potentially override the body's controlled absorption system and leave us with more iron in storage than we need.

The body has no internal mechanism for excreting excess iron. It simply contains it in protective protein molecules and stores it in tissues, preferentially glandular tissue such as that of the liver and pancreas. In the past, humans did have a way of dropping excess iron—we were full of parasites, creating continuous minor gastrointestinal bleeding—iron contained in the hemoglobin was in this fashion dumped from the body. This constant blood loss was likely the reason we evolved with mechanisms to protect iron and none to eliminate it.

Those of us living in developed areas of the world are now free of the parasitic bleeding that reduces iron stores, but also subject to unnatural foods that are either fortified with iron, enhance the absorption of iron, or both. Over years, this can result in dangerously high levels of iron in the body.


So What's the Problem?

The primary problem with iron is its pro-oxidant characteristics: it's very good at helping create free radicals—molecules with unpaired electrons with consequently low stability and high reactivity—such as the hydroxyl radical.

In heart attacks and strokes, the bulk of the tissue damage is actually not due to oxygen deprivation, but instead to the re-introduction of oxygen. When an artery is occluded, tissues beyond the blood's reach are deprived of the accompanying oxygen and begin dying. Necrotic cell death is not orderly—pieces essentially fall apart freely—and this allows the free exposure of formerly safely stored iron. When the vessel occlusion is repaired, whether medically or naturally, a huge influx of blood bathes these broken tissues and the exposed iron, which reacts with the new oxygen. This violent reaction can result in severe tissue damage.

Excessive iron storage may also be a factor in the development of certain cancers such as of the liver, atherosclerosis, reduced insulin production and insulin resistance. The research on which these ideas are founded is—like almost all research in similar areas—not conclusive, but does appear relatively convincing.

Regular flushing and replacement of iron also means the body will have fresh material for hemoglobin and other iron-dependent structures instead of relying on continual recycling. The benefit of this is entirely speculative, but no potential drawbacks seem to exist.


Testing Your Iron Level

If you're interested in having your stored iron level tested, don't let your doctor test your hemoglobin level—this is common but inaccurate method. Instead, ask for a serum ferritin test, which measures the amount of ferritin in the blood. This number is 10 times lower than your iron level; that is, if your serum ferritin number is 70, you have 700 mg of stored iron. Certain individuals may show inaccurately high ferritin levels, including alcoholics and those with infections, severe inflammation, and cancer.

A healthy amount of stored iron is around 500 mg. 1000 mg may be problematic. 150 mg is a safe low-end threshold. Less than 100 mg is indicative of iron-deficiency anemia.


Donating Blood

Getting rid of blood is not hard—there are a lot of people out there more than happy to relieve you of some. They won't even charge you for it.

My own blood donations have been consistently positive experiences. Aside from enjoying scintillating conversation with the lovely phlebotomists and volunteer post-drainage babysitters who like to remind me I was born in 1980 while making continual subtle advances toward my defiant position with the donut tray, I've noticed a significant improvement in energy in the days following the donations. I've also been perfectly able to train at adequate intensity and volume within several hours of donation, despite my repeated and convincing assurances to my concerned caretakers that I would never dream of engaging in such reckless behavior—but of course my longstanding habit of lying to women is not relevant to this particular discussion. Performance in high-metabolic-demand training such as CrossFit will be below average with a pint less blood in your system, but generally donation frequency is limited to eight weeks—a regular blood donation schedule that coincides with a week of limited training volume and intensity could be a simple method of ensuring periodic active recovery in your long-term training strategy.

The bottom line is actually very simple: while the potential health benefits of regularly donating blood have yet to be demonstrated conclusively, with proper nutrition and lifestyle, and with consideration of known contraindications, blood donation poses little if any risk. That being the case, the prudent course of action is to make regular blood donation a habit. The worst case scenario is that your blood helps save the life of some cute little baby and your metabolic conditioning is compromised for a week every two months.


American Red Cross
www.givelife.org