Date: September 25, 2019 Source: American Chemical Society
researchers have engineered genetically encoded protein crystals that can generate magnetic forces many times stronger than those already reported.
Each crystal contained about five billion iron atoms and generated magnetic forces that were nine orders of magnitude stronger than single ferritin cages. By introducing crystals that were pre-loaded with iron to living cells, the researchers could move the cells around with a magnet.
https://www.sciencedaily.com/releases/2019/09/190925083802.htm
Hat tip Jimstone.is
Yes, there are multiple references on this page. Jimstone.is is the website for the investigative reporter. He has his own ideas based on his research, and he posted a link to the article at the top. He also referenced a study on rat brains that had magnetism modifying behavior. I did an image search looking for related information and came across the article that referenced scientists having superpowers like Magneto and the Dark Crystal ballet.
The commonality between the three papers besides magnetism is the stated design of them controlling bodies, or behavior modification.
We can assume the anemia wasn't their primary goal. :)