Swallowing vitamins like horse pills, getting bad breath. Are pills not good?

Vitamins & Halitosis. Vitamins and supplements can cause gastrointestinal upset and can exacerbate bad breath. Gastrointestinal upset may not be evident. Best to get your nutrients from a balanced, healthy diet. Look at http://www.Hsph.Harvard.Edu/nutritionsource/healthy-eating-plate/ for great guidelines on foods to eat.
Maybe. The vitamins may be causing some acid reflux which can cause bad breath. The two problems could also not be related at all. I would try different vitamins to see what happens.