PH of urine vs. PH of saliva

Could someone please shed some light on this for me as I am puzzled: The PH of my first urine in the morning hangs around 6.0 ( low, I know...), while the saliva is around 7.5 to 8.00. Are they not supposed to be closer together?
My fiance's urinary PH is around 7.5, better than mine, although we eat the same main meals, except his diet is worse because he gets into candy, honey, chocolate bars, beer, while I stay away from these. He is also a carbohydrate junkie, will have a bowl of cereal before going to bed, I don't. Yet, look at his PH!
Both my fiance and I drink kombucha 3 times a day and also eat other fermented foods ( I make sauerkraut)and plenty of vegetables and fruit. He has a persistent form of skin cancer, squamous cell carcinoma, so we are aware of the importance of PH. His good PH does not eradicate the skin cancer...
Obviouosly, my body reacts differently than his.
So, what do I need to do to better my PH ? I don't want to change our joint diet as he seems to be doing fine on it. I have had a recent urinary tract infection; after taking herbs for it the discomfort is totally gone, but there is still some cloudiness and foam in the urine. (I took baking soda for a couple of days, but it upset my digestion, so I stopped).
Thanks in advance.