A part of my theory...but also fact: parasites can manipulate their host to varying degrees. For instance: there's a worm that inhabits crustaceans like lobsters, crayfish....and when the worm has finished laying her eggs, (so the crayfish is full of live, hatching parasites) the worm somehow changes the crayfish's behavior so that crayfish commits suicide, basically. Against all common sense, the crayfish ventures into the sunlight, where it is instantly eaten by a bird, which is the parasite's secondary obligate host. It gets complicated....
How does this relate? I think OUR parasites manipulate Our preferences. For example: I get salt CRAVINGS and I get deficient easily. I must have envt temp exactly correct (73?) or I get hot/cold intolerably fast and extreme. If I'm getting dehydrated, I get parched. If I'm hungry, I can be RAVENOUS but I get full after three bites of food.
They keep me where they want me....it's much like being a veal calf.
So, it seems my revulsion at watching films about parasites could be one such manipulation by my parasite. Certainly, my bugs don't benefit from my research. lol