My die - off (strong flu like symptoms) was very specifically at the start of using Kefir when my diet was very strict and I was slowly introducing Kefir. It lasted a week. I'm ok now.
Sorry if I didn't make this clear.
I've been cleansing (both candida and parasite) for a long time now (years!) and my food sensitivities are greatly reduced. I can tolerate small amounts of fruit/sugar/carbs/dairy as long as I rotate the foods and don't consume too much.
But I did have a strong reaction to the introduction of Kefir which these days (for me anyway) is unusual. If I continue to improve healthwise it will all be worth it!