And before you started keto your blood pressure was normal even when you drank your coffee?
no.
I had been low carbing (c.80g carbs/day) for years before I started keto (less than 20g carbs/day), and my bp was always high, and I drank 1 cup of coffee, usually decaf, each morning, over a 10-15 year period.
I know you are desperate to avoid giving up coffee, but it was definitely coffee that sent my bp high.
Maybe that isn’t the case for you, but you will never know if you don’t test it.
I did an exhaustive series of self tests over a couple of months, using both caff and decaf coffees.
They both send my bp high. The rise started about 5 hrs after drinking one cup, was at its highest at around 10-12 hours and then took 3-4 days - yes, DAYS - to drop back down to the start point. The peak was consistently in the 160/105 area, but had never been picked up at docs or at the clinic because I do not attend appts during the early evening. A few times I clocked 185+ and over 110
I ran the test repeatedly, because, like you, I didn’t want to have to give up coffee, and I was very reluctant to accept that decaf was almost as bad as caf.
If you want to know whether coffee affects you, then you need to run similar tests. Doctors won’t run then for you.
I was happy to run them because I would rather drop coffee than have a series of totally unnecessary, debilitating and possibly terminal strokes.
All you need to test things yourself is a home bp monitor, some caf and some decaf, and a willingness to give up coffee for 7-10 days before each round of tests.
hopefully you will find that coffee can be, for you, eliminated as the cause of you raised bp.