I have serious auto-immune conditions related to a gene called HLA-B27. Over my life they have got worse and worse. People with my set of conditions have a mean life expectancy of 10 years less than the mean. I'm going to live a lot less than that as mine kicked in early and my inflammation has become so bad it causes seizures.

Rheumatoid arthritis is linked to HLA-DRB1 and there is increased risk with other factors - PTPN22 and STAT4.

It's possible that microplastics are one potential trigger of auto-immune diseases. Various viruses and bacteria can trigger it. - several types of flu - H1N1 (bird flu), Covid - when people talk about long Covid and the overwhelming exhaustion and brain fog they are the primary symptoms of many auto-immune conditions.

I originally trained in physiology (neurophysiology to be precise) and I have put in a lot of private study into this. The gut biome is definitely involved as probiotics reduce inflammation. The natural probiotic that I have had the most success with is Kefir as it contains the greatest variety of bacteria, it's good to take others as they provide even more variety.

I have also looked at the timeline and when this type of condition started getting more and more prevalent. My conclusion is that antibiotics are almost certainly contributive factor. They can totally kill off the biome in your gut and freak it out. The fact that antibiotics are given to farmed animals on pretty much a permanent basis means that antibiotics are in pretty much all meat which means there is no avoiding it if you are a meat eater or live around farmed animals.

Vegetable oils are possibly another factor as they can mess with the biome too. They are a modern development and have caused the omega6:omega3 ratio to scoot up to 30:1 when it should be 1:1. That causes serious imbalances in the biome. That means being a vegan doesn't help either.

When things get really bad I go on a long fast - 3 days minimum, up to 2 weeks. Re-introduce food gently starting with kefir and other fermented stuff first. The first few days are hard but you actually start to feel healthy after that. The fast must be zero food otherwise you can never reach the repair phase where your body burns fat.

Another thing that helps is gardening, especially getting on all fours and doing weeding by hand. I get lots of cuts and scratches and it gives my immune system something to do rather than attack me.

Some types of plastic do mess with the biome whereas others are hormone disruptors so microplastics probably do add to the problem.

Try your mother out on some kefir before thinking about a fast as fasts can be risky. Lot's of omega 3 too.