Vitamin D3 supplementation boosts the immune system or get 30 min of full sun half naked. I have seen the incidence of colon cancer plotted on a US map which shows more incidence in the northeast.
Supplementation with resverotrol.
Sprinting tabata wind sprint style.
Edit: Now that I see you are in Canada...Vit D3 is even more important.
Paleo, a good sleep schedule, and a lot of hard exercise left me basically immune to ever getting sick, but it didn't happen right away. Perhaps you could keep trying to improve your lifestyle and just see what happens?
To me, it seems like a bad idea to start messing with supplements and shit when you still (probably) have a lot of improvement to make with your basic lifestyle, and a lot of damage to heal from your past life. IMO, just be patient and keep working on getting more paleo, and doing more exercise, etc. Don't get antsy and try to accelerate the process with weird shit like supplements.
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