Microplastics and the brain
Yes, I spent last week revamping my food storage and cookware collection
An article came out in Nature Medicine this month showing that microplastics are increasing in people’s brains as measured postmortem. It also showed that people with dementia at the time of death had significantly more microplastics in their brains than age-matched people without dementia.
Quote from that article:
"even greater accumulation of MNPs was observed in a cohort of decedent brains with documented dementia diagnosis, with notable deposition in cerebrovascular walls and immune cells. These results highlight a critical need to better understand the routes of exposure, uptake and clearance pathways and potential health consequences of plastics in human tissues, particularly in the brain."
The most common type of polymer found in the brain was Polyethylene or PE (orange bar in panel b. below).
About PE from Wikipedia:
”Polyethylene or polythene (abbreviated PE; IUPAC name polyethene or poly(methylene)) is the most commonly produced plastic.[7] It is a polymer, primarily used for packaging (plastic bags, plastic films, geomembranes and containers including bottles, cups, jars, etc.). As of 2017, over 100 million tonnes of polyethylene resins are being produced annually, accounting for 34% of the total plastics market.”
BPA, which many people try and eliminate, does not actually accumulate in the body. Concerns about BPA stem from its estrogen-like activity.
You can actually see microplastics in the brain. Below are microscope images of plastic in human brain from the Nature article:
A few people pointed out on LinkedIn that just because microplastics are seen in the brain more often in people with dementia, that doesn’t mean that the microplastics caused their dementia. It is true that people with dementia have “leakier” blood brain barriers on average so they may just have been more prone to having microplastics in their brain rather than microplastics causing their dementia.
The jury is still out on how harmful these microplastics are but these pictures were enough for me. Plastics in brains do not look good. I was already BPA-free but am now switching to eliminating as much plastic as possible from storage and cooking of my food and drink. It’s not that hard to switch to glass and it’s likely better for the environment anyway (see the discussion on that post).
Microplastics are more likely to leach out when heated but I’m not taking any chances even with cold storage. Apparently silicone ice cube trays don't leach micro-plastics and I found some glass storage jars with bamboo lids. I have given up my Nalgene water bottle for a glass bottle. I have also switched to steel and ceramic pots and pans to avoid microplastics leaching from the non-stick coating on some of my pans. One person on LinkedIn even went so far as to refit their dishwasher with metal instead of plastic parts.
In conclusion, while we don’t know definitively if microplastics are a risk factor for dementia, I think we know enough for me to recommend that people who are concerned about their brain health take steps to limit their microplastic exposure.