I should preface this with "I'm a fiction writer."

If someone were to implant extremely strong magnets under their skin and attach an attracting magnet to the outside, how would that affect the skin and/or muscles between the two? I guess biohacking and magnetic implants are already a thing, but I'm imagining something stronger that would take some effort in separating if the two objects were already attracted.

I'm assuming it would lead to significant bruising as the blood vessels between the two magnets would probably break. Could it lead to permanent nerve damage? Could the person make a full recovery if the magnets were removed from their body?

Bonus question...would any of this change if the magnets were electromagnets...?

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    $\begingroup$ It wouldn't lead to bruising; the capillaries couldn't fill between the magnets if they were strong. That would lead to tissue necrosis. "Full recovery" depends on your definition. You certainly would not die. $\endgroup$ Commented Nov 18, 2021 at 21:18
  • $\begingroup$ @bob1 Cross-posting to multiple SE sites generally isn't allowed. meta.stackexchange.com/a/64069/166737. But I will migrate it there since it really doesn't meet prior research requirements here. $\endgroup$ Commented Nov 18, 2021 at 21:51
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    $\begingroup$ The magnets are a red herring; the source of the force is irrelevant. It would have exactly the same effect as crushing the tissues with pliers, with all the same risks. $\endgroup$
    – AlexP
    Commented Nov 18, 2021 at 22:42
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    $\begingroup$ @CareyGregory, thanks for the migration. I wasn't sure if it belonged in WB, because I asked something medical-related awhile ago that I thought was still WB related and was told it was posted in the wrong SE. I thought I'd correct my mistake this time, but I guess not. throws hands Still learning what allows something to be in one SE and not the other. Thanks for putting it where it belongs. $\endgroup$
    – Jay Dee
    Commented Nov 18, 2021 at 23:15
  • $\begingroup$ I think this one has just enough mad scientist, dystopian society qualities about it that it might pass the censors. You could probably edit to include cultural information like: is this really some kind of fascist-socialist dystopy where everyone has magnets in them; or is this just goober who shoved some magnets under his skin to see how many hits his magnet fail video compilation can get on the yootoobes? $\endgroup$
    – elemtilas
    Commented Nov 18, 2021 at 23:49

2 Answers 2



One of the great "practical experiments" we used to do, way back in the last century, was to cut the big magnets our of PC hard drives. They make fun toys, and since they were paired, you got two for the price of one. One of the first lessons learned playing with strong magnets is to not let the magnets smack together with any part of your body in between them.

Two kinds of natural forces do not care what parts of your anatomy are caught between them: strong magnets & door jambs. Pliers also rank up there pretty high as well.

At the very least, someone with a sufficiently strong implanted magnet would experience is the pain of magnetic things snapping onto their skin. A little sting here, a small bruise there. Hovering a strong magnet over the implanted magnet will almost certainly cause the character to lose control of the external magnet and will snap smartly onto his skin. Pain & hematoma are certainly possible outcomes. It's also possible to lacerate the skin or puncture it if the edge of the external magnet is at all angled and hits the skin the right way.


As you can see, there is not a lot of tissue above this pacemaker battery pack. If it were a magnet and a strong magnet were brought close enough, they would snap together.

Very few implants are placed under muscle (certain breast implants and almost all orthopedic implants are common exceptions). They're designed not to interfere with the nerves & muscles above. Most implants are nestled cosily in the subcutaneous fat. If you did implant a magnet under the muscle, your character would risk damage to the muscle as well as skin & subcutaneous tissues when the magnets smash together like two miniature planets.


Nerve damage is a possibility if the implanted magnet is under a nerve and the external magnet presses on it for an extended period of time (like a couple hours or more). Unless you are proposing some kind of crazy dystopy, no good surgeon will place an implant under a muscle or major nerve, e.g. in the arm or hand. Implants are frequently placed in the arm (non-magnetic / titanium orthopedic plates & screws; A-V fistula grafts, some hormone therapy delivery mechanisms) but none are intended to interact with external forces, including MRI machines or HDD magnets.

Very strong magnets can indeed cause devastating crush injuries. Strong enough magnets could fairly easily break bone as well as crush soft tissues.

Implant removal is a fairly trivial procedure and is done frequently (removal of orthopedic hardware, removal of breast implants, exchange of pacemaker battery packs). If the implant is done right, and not as the brainchild of some mad scientist, then getting it our should post no difficulty for recovery.

I don't think it would make any difference if the magnets were electromagnets, except that obviously your character would have to activate the internal magnet to be affected by the external magnet.

Phile Under Phun!

Small magnets such as your mad scientician might implant in a character aren't very powerful ... but if your character has a magnetic implant of some kind and comes into the range of a real magnet, then the fun times really begin!

Here's how strong an MRI magnet is, for example. Probably not strong enough to suck your character in, unless the implants are large, but it is possible that it might get torn out of his body or cause pain and discomfort while it's trying to escape the confines of the skin!

  • $\begingroup$ Everything about this hurts. haha. Thanks for this. A couple of clarifying questions: could you explain what your second image is? I understand the pacemaker, but not the diagram. Also, with electromagnets, if electricity has to be running through them in order to work, would that shock or electrocute the person/tissue? Or is that not how electromagnets work? $\endgroup$
    – Jay Dee
    Commented Nov 18, 2021 at 23:33
  • $\begingroup$ The second image is a titanium plate -- it's designed to hold broken bones together without causing a) damage to the muscles and nerves that lie on top of it and b) problems with MRI magnets. Electromagnets: no, the electricity runs through a coil of coated wire. No electrocution there! $\endgroup$
    – elemtilas
    Commented Nov 18, 2021 at 23:55
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    $\begingroup$ MRIs can be fun for a variety of reasons, as well, because they use magnetic fields that rapidly change polarity. This can be a real risk for people who suffered major trauma obscuring a piercing (genitals or belly-button are common problems) because small enough magnetic or ferromagnetic materials will heat up in such a field. Small magnets seem much worse from this perspective. $\endgroup$
    – jdunlop
    Commented Nov 19, 2021 at 0:58

The fact that they are magnets, in itself, has no negative effect on the body. Arguably it would have beneficial effect if you listen to those who put magnets into casts to speed bone healing (placebos work for some people).

As mentioned, you would have crushing damage between the two magnets.

There is a possibility that a strong enough magnet near the brain would cause some disruption but, quite frankly, I'd be more concerned with the 50+ pounds of metal that you shoved under someone's scalp.

The only medical drawback that I can see has nothing to do with magnetism. It depends on what the magnet is made of or coated with. There may be chemicals in the material that leaches into the skin or, like any foreign body, it could trigger an immune response.

The magnet being an electro magnet has no effect other than it is now bulkier and requires a power source. "Yeah, I'm fine with the magnets in me. Please don't trip over the cables running across the floor."


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