Hi Louise,
I'm Type 1 (35 years) and had to go onto high blood pressure meds in my early 20's (I'm now 46). I was on the meds for over 20 years and during that period nothing lowered my blood pressure, not even when I lost 4 stone in weight (low cal, low fat diet) and started exercising. In April this year I started the ketogenic diet and have been on it ever since. After 3 months of following the keto way of eating, my doctor had to take me off my blood pressure meds because I started suffering from dizzy spells and after monitoring my blood pressure every day I realised it was because my blood pressure had dropped so much it was actually bordering on being too low. I was gobsmacked!! Now, 3 months later after not having to take a single pill since, my blood pressure remains healthy and toward the lower end of normal. I can only put this down to the keto diet, but hey, I'm no medical expert so who knows!
Everyone is obviously different and I'm not saying the LCHF diet will help your husband with his blood pressure, but I just wanted to give you a little bit of hope. Stick with it, and fingers crossed for some good news!
Erin