Yes, the two are related! It was a light bulb moment for me too because my partner's hands (fingertips and palms mainly) are sometimes just dreadful, all skinned and splitting and peeling. It would be great if he could make a good push forward after all he's done to improve the eczema on the rest of his body, which is all but completely gone.
Don't despair! It is a seemingly random group of mainly vegetable foods (wheat bran, lentils, almonds, oats etc) which shouldn't be too hard to avoid but it isn't intuitive in any way, so you will need to get used to a diet sheet. Anyway, if the diet helps you can always stray from it occasionally and take an antihistamine. Gardening with bare hands should also be avoided as there is nickel in soil. pennstatehershey.org/c/docu...
I can see a lot of people getting flummoxed because they've taken the trouble to avoid milk to fix their eczema, but if they're using almond, oat or soy milk they could be going back to square one. This is the part my husband is struggling with because he quite likes his soy milk and doesn't really want to have to get used to something else now.
I guess we should be glad he only has it on his hands and not his feet. Small mercies etc?
You've confirmed for me that gps aren't bothered about delineating the various sorts and causes, but so much misery could be avoided so simply if they would.