Several months ago I saw a study claiming that decaf coffee prevents withdrawal symptoms, even if you know it's decaf. I was getting headaches pre-coffee in the morning, and tried it, and it worked so well I quit caffeinated coffee without any trouble. Just felt a little slow and sleepy the first week.
Sorry, I misspoke, and that's my experience. I still had slight symptoms, but they were reduced by at least 90%. I'd found it pretty difficult to quit coffee before, but switching to decaf was effortless.
https://www.sydney.edu.au/news-opinion/news/2023/02/14/decaf...