I took an extra daily dose of folic acid yesterday and today i developed heartburn, can that cause heartburn?

Could depend on dose: I've had patients tell me that Folic Acid sometimes causes some gastrointestinal distress and heartburn, and it is a listed side effect. Higher doses seem to do it more. That being said, most people taking extra Folic Acid are also pregnant - which is prime time for developing heartburn symptoms, independent of Folic Acid use.

Poor digestion: Heart burn is a sign of undigested food increasing Lactic Acid and peroxide in stomach - to ease the issue take betaine hcl with bromelain it will help digestion and pain.