What if … Magnets attract the iron in our blood? – HSMAG makes a typical claim that magnets attract iron blood:

The extraordinary success of the scientifically-designed Genuine HSMAG magnetic underlay is because it improves your circulation so efficiently. The magnetic force stimulates nerve-endings to improve blood flow to injured or swollen joints. It does this by drawing trace elements, for instance, iron, towards the magnets. The human body contains about 5 grams of iron, much of it in the form of haemoglobin which plays a vital role moving oxygen from your lungs around your body. The improvement in blood circulation eases the swelling around injured or deteriorated joints, and thus the pain.
BioMag clearly states that iron in our blood in the form of haemoglobin is drawn towards the magnets. Part of this is true. Part of it is false. It is perfectly true that the haemoglobin in our blood contains iron. However it is completely false that magnets attract this iron. The iron in the haemoglobin is of a different configuration to that in an iron nail, a configuration that is not magnetic, and thus the magnets used in magnetic therapy products have no hope of attracting haemoglobin iron. The iron in your blood might as well be made of plastic for all the effect magnets have on it.
In fact, if magnets did have a noticeable effect on your blood flow, I believe they would cause more harm than good.

magnets-attract-iron-blood

magnets-attract-iron-blood

To explain this, let’s assume for a moment that magnets work exactly as magnet therapists say they do — they attract blood. Let’s assume that science is wrong, a view recently expressed to me as, “Scientists! What do they know?”

First let’s remember that ‘attract’ means to ‘pull towards’ the magnets. Assume you have an injury on your stomach and you sleep on your back, on top of a magnetic underlay. Since the magnetic therapists tell us that magnets attract the blood, all your blood will be pulled towards your back, towards the magnets, and away from the site of injury. All your blood would tend to pool at the back of your body, closest to the magnets. Rather than improve the blood flow to the injury, the magnets would reduce it. Likewise the magnets would pull all the blood to the back of your brain, starving the rest of your brain. This can’t be a good idea since we know that brain cells starved of oxygen enriched blood for greater than 5 minutes will result in brain damage. And yet people spend hours every night on these blood-sucking magnets.

No Underlay Magnetic Underlay

Also note that if magnets really do attract blood, this won’t do anything to improve blood circulation. Blood will simply be pulled towards the magnets, and if they are strong enough, it will stay there. The oxygen will be removed by the cells along the back of your body, but the blood will not be able to flow back to the heart and lungs to get more oxygen because it is being held there by the magnets. Every cell in your body will die. You will die.