Some time ago there was a post about a study which shows a small amount of baking soda (1/4 tsp) per day has been shown to work on the spleen and lower inflammation. I have tried this for four months and the result, for my version of PMR is absolute zilch. In fact my inflammation markers are as high as I've ever known them to be, and I'm dealing with an unprecedentedly severe and intransigent flare.
Rating: no stars out of five.
Edit: Additionally it had no beneficial effect on the swollen knee and osteoarthritis I've suffered from since last summer.
Further edit. Lots of info on internet, from reputable sources. This is a clear overview: