I was really low on serotonin by the time i saw my naturopath (and i have had candida probs and now have leaky gut).
I found eating kefir initially gave me a significant mood boost (feelings of calm, well-being etc), i think because it contains tryptophan, a precursor to serotonin.
I found i was reacting to a lot of candida diet and protocol foods and supplements. My naturopath tested me for food and supplement allergies and i now eat by this safe list (which is quite close to a candida diet anyway). I think my gut is getting a little better as i am tolerating a few more foods but it’s taking a while.
(Also, i had other parasites and bad bacteria in my gut, so a candida diet alone wasn’t going to get rid of these.)