Unsupported: The volume of a COVID-19 vaccine dose is too small to contain a device strong enough to hold a magnet.
FULL CLAIM: COVID-19 vaccines contain metals or microchips that cause magnets to attach to the arm of vaccinated people
Around mid-May 2021, multiple videos (examples here, here, and here) claimed that COVID-19 vaccines caused magnetic reactions in vaccinated people. The videos purportedly showed that magnets attached to the arm where people received a COVID-19 vaccine, but not to the unvaccinated arm. The so-called “magnet challenge” went viral across social media platforms, including Instagram, Facebook, and Twitter, receiving hundreds of thousands of interactions.
While some posts didn’t try to explain the phenomenon, others claimed that COVID-19 vaccines contained metals or microchips that attracted the magnets. None of the videos provided verification that the people appearing in them were actually vaccinated against COVID-19. Regardless of whether they received the COVID-19 vaccine or not, the claim that COVID-19 vaccines “magnetize” people is inaccurate and unsupported by scientific evidence, as we explain below.
None of the authorized COVID-19 vaccines contain magnetic ingredients
All materials react to magnetic fields in some way. However, these magnetic forces are, in general, so weak that most of these materials are effectively non-magnetic. Only a few metals, including iron, cobalt, nickel, and some steels, are considered truly magnetic and are attracted to magnets.
Lists of the ingredients in all the COVID-19 vaccines authorized for emergency use by the U.S. Food and Drug Administration (FDA) are publicly available. The mRNA COVID-19 vaccines from Pfizer and BioNTech and Moderna contain mRNA, lipids, salts, sugar, and substances that keep the pH stable. The COVID-19 vaccine from Johnson & Johnson contains an adenovirus expressing the SARS-CoV-2 spike protein, amino acids, antioxidants, ethanol, an emulsifier, sugar, and salts. None of these ingredients are metals, and therefore, none of them are magnetic.
The Oxford/AstraZeneca COVID-19 vaccine contains similar ingredients to the Johnson & Johnson vaccine, but includes magnesium chloride as a preservative. Although magnesium is a metal, it is also non-magnetic, both in its elemental form and as magnesium chloride salt. In fact, higher amounts of magnesium are naturally present in the body, in many foods, and in dietary supplements, and they don’t cause magnetic reactions in people.
Finally, the volume of a COVID-19 vaccine dose is very small, ranging from 0.3 ml in the Pfizer-BioNTech vaccine to 0.5 ml in the Moderna and Johnson and Johnson vaccines. According to experts, even if the vaccines contained a magnetic ingredient, the total amount would be insufficient to hold a magnet through a person’s skin. Michael Coey, a physics professor at Trinity College Dublin, explained to Reuters:
“You would need about one gram of iron metal to attract and support a permanent magnet at the injection site, something you would ‘easily feel’ if it was there […] By the way, my wife was injected with her second dose of the Pfizer vaccine today, and I had mine over two weeks ago. I have checked that magnets are not attracted to our arms!”
This Instagram video illustrates how a magnet (or any other small object) can stick to people’s skin without the need for any magnetic force.
Claims that COVID-19 vaccines contain microchips are unfounded
The claim that COVID-19 vaccines are magnetic because they contain microchips or tracking devices traces its roots to a conspiracy theory that has persisted throughout the pandemic. Despite being debunked many times, the baseless theory that COVID-19 vaccines include secret devices for tracking the population emerges from time to time in different forms.
Such claims led the U.S. Centers for Disease Control and Prevention (CDC) to explain on its website that COVID-19 vaccines don’t contain microchips or tracking devices:
“No, the government is not using the vaccine to track you. There may be trackers on the vaccine shipment boxes to protect them from theft, but there are no trackers in the vaccines themselves. State governments track where you got the vaccine and which kind you received using a computerized database to make sure you get all recommended doses at the right time. You will also get a card showing that you have received a COVID-19 vaccine.”
The claims that the COVID-19 vaccines contain magnetic microchips are incorrect for multiple reasons. First, any microchip contained in a COVID-19 vaccine would need to be small enough to fit through the syringe needle. Vaccination generally uses 22 to 25-gauge needles. “Gauge” indicates the size of the hole that runs down the middle of the needle. The higher the gauge, the smaller the hole. These needles have a maximum inner diameter of 0.5 mm. Current microchips aren’t small enough to fit through the syringe needle. Second, even if a microchip of that size exists, it would be too small to hold a magnet through the skin, for the same reasons explained by Coey above.
Finally, all COVID-19 vaccines are supplied in multidose vials containing five to 15 doses, depending on the manufacturer (see dosing information from Pfizer and BioNTech, Moderna, and Johnson & Johnson). This would make it impossible to guarantee that all individuals receive a chip. Some people could receive several chips, while others receive none. Furthermore, many of the devices would likely remain in the vial or get stuck in the syringe.
Claims that COVID-19 vaccines cause magnetic reactions are unsubstantiated and implausible. COVID-19 vaccines authorized for emergency use by the FDA don’t contain metals or other magnetic ingredients that could cause a magnetic reaction in vaccinated individuals. Furthermore, no component or microchip that fits in the volume of a COVID-19 vaccine dose would be strong enough to hold a magnet through the skin.