If you have certain parasites, the immune system kills a lot of your bacteria. Much of these bacteria produce enzymes and vitamins esp. B types, that energize cells, and break food down during digestive processing. So, your bacteria is a big part of your body chemistry.
Yogurt are lactobacteria, which live higher up in the small intestine. Lactose intolerance and\or other imbalances may be present.
Have you been positively identified with problematic B. Hominis? Microscopic findings should reveal very high levels, or a type that is distinguishable by differentials in PH value. This can be observed as the B hominis with reddish halo around it. Shroom