If I were taking both, I would take them separately and perhaps up my normal amount of vitamin C. Even though Linus Pauling used to add baking soda to vitamin C to make an effervescent beverage, baking soda destroys vitamin C that has not been absorbed into the body. That means that the old wives tale of adding baking soda to boiling vegetables is NOT a good idea, since it destroys the vitamin C. Of course, we shouldn't be boiling our vegetables anyway for the most part, should we?