fermentation and yeast and candida

Wondering about the yeast and if it causes candida?

Candida is a yeast (Candida albicans) that is a normal part of the human microflora but can grow out of balance. It is different that the yeasts used in fermentation (generally Saccharomyces cereviciae) but feeds on the same thing: carbohydrates. I am not a clinician, but I have heard many reports of people getting rid of Candida overgrowths by (1) avoiding carbohydrate-rich foods including ferments; and eating lots of live-culture bacterial ferments made from foods that are not especially carbohydrate-dense, specifically vegetable ferments like sauerkraut or kimchi and dairy ferments like kefir or yogurt.

Sandor Katz wrote:... yeasts used in fermentation (generally Saccharomyces cereviciae) ... live-culture bacterial ferments...

Something I find confusing...
Yeast and bacterias are not the same thing...
So what causes natural fermentation when nothing is added?