If you’re allergic to everything, it may interest you to look into mast cell activation or histamine intolerance. There’s also a theory in alternative medicine circles (and an entire Ray Peat forum which is simultaneously informative and nonsensical) about how your lymph, which carries a lot of your fat-soluble vitamins in chylomicrons, is involved with autoimmune issues and cam be out of whack. And so their answer is to take larger amounts of fat soluble vitamins. This can be dangerous if done with animal derived sources of vitamin A, like your skin can start sloughing off and you get wicked nausea and diarrhea and headaches. Theoretically, these symptoms in the Ray Peat world mean you need more vitamins D, E, and K to balance the vitamin A toxicity effects.

I have an issue with absorbing fats/good and my allergies are worse when I’m having flare ups, so I do see some merit in this theory. I have found that supplementing fat soluble vitamins, (+omega 3 and 9, and various other B vitamins and vitamin C, and zinc and iron and copper and selenium), has helped my allergies out a ton. I really really recommend that if you have systemic allergies like this, to see if supplements/vitamins help.