Muscle testing has helped me a lot with this. In 2014 I tried gelatin at night for sleep because of its high glycine content. It hit me like a truck with a severe detox reaction - very tired, spacey, etc. At that time I was detoxing a lot - I reacted to anything that could possibly have a "cleansing" action - e.g., cayenne, apple cider vinegar, chlorella, and lot of stuff that for most people is pretty benign. So my initial thought with the gelatin was, okay, that's bad for me. It made me feel horrible, I'd better stop it.
Then I did some reading about glycine and learned it was important for Phase II liver detoxification. So that explained my reaction. I was detoxing in response to something just about every week, not intentionally. So I had my chiropractor test me (via muscle testing) on glycine, and to my surprise, I reacted positively to it, but in a much smaller dose. So I started taking glycine (instead of gelatin) starting with a very small dose over the next 6 months. I started with a dose I could tolerate without too much discomfort. I gradually increased it over the 6 months and my detox reactions got less and less, and by the end of 6 months I no longer reacted to the glycine in a negative way.
It's a long story but the same thing happened at the same time with inositol and glutamine, though my reaction to them was much milder. But the end of 6 months, no more detox reaction.
But what really surprised me at the end of the 6 months was that I no longer reacted badly to cayenne, apple cider vinegar and everything else that used to make me feel sick. I believe the glycine especially plus the other two things got my detox pathways working properly. What used to be a huge continual problem for me was gone. And I still take glycine and inositol to help with sleep.
So I'm not advising
@sb4 or anyone to do what I did or take something that makes them feel crappy. But I did want to point out that it's very possible this is what was happening. Detoxing is a known initial reaction to Cellfood.
Muscle testing has helped me with a lot of other things - e.g., one glass of wine used to make me sick for an entire day, and 2 glasses would leave me feeling sick for 3 days. This was in the early 2000's. Well, my chiropractor again was extremely helpful with muscle testing. He said my liver was overloaded with toxins from a job I'd had a few decades before (heavy exposure to chemical solvents) so it had trouble processing the wine. I did a liver detox under his supervision for a month - I felt like crap the entire month - and afterwards I was able to drink wine again like a normal person without getting sick. This was really nice for me. Also, my digestion was much improved. Before the detox, I had trouble eating in morning, I felt sick most of the time. And that horrible sick feeling disappeared after the detox.
