Why did butternut squash make my fingers dry and yellow?

It's definitely a very real reaction. I'm not sure exactly what in the squash it is that causes it, but since different people react differently - some people have strong reactions like you, some people have mild ones, and some have no problem at all - it seems to be some sort of mild allergic reaction. It's often called contact dermatitis, but that's a very generic term and doesn't really mean anything you don't already know. I'm not sure exactly what component of the squash it is that causes it, but I don't think it's carotene or potassium. It's likely some more complex molecule that tends to be present in various winter squashes.

Images from http://foodworld-eva.blogspot.com/2010/01/squash-reaction-on-skin.html.

You can avoid it by completely wearing gloves while working with the squash, or if you're lucky, you have someone else with you who can handle the squash without problems. For many purposes, like soup, you can also simply cut the squash in half, roast it, then scoop out the good stuff. But if you do really need to peel it and cut into chunks, your best hope is just to try to avoid touching it too much. You'll also want to wash your hands immediately after, or even a few times while you're cutting if it takes a while.

If you do end up with this despite your best efforts, cortisone cream can help relieve the reaction afterward.

(And as for your soup, there's nothing wrong with letting more moisture escape in exchange for browning. You can always just add more water or stock back into the soup. This can even be a good thing, since it lets you replace water with a more flavorful liquid.)

Okay happened to me too. I did notice a clear gel like substance coming from the squash when I chopped and peeled it, I read that's a natural substance to "protect" itself from damage, like sealing up a cut or wound. I cut up 4 of them, only the first one had this. So may be from varying ripeness. I washed my hands after cutting them all up,(since they were so orange) as soon as my hands began drying they started reacting... slick film, tightening, a little numbness. I started washing them again and really scrubbing them, can't tell if it is the film or layer of skin that comes off I think it's the dried film from the squash. It takes some hard scrubbing but it will come off, hands very dried out afterwards.

I've had this happen before after preparing butternut squash. Once, I also found that my fingers turned shiny. I realized that the wax that was on the butternut squash had gotten on my hands since I had rinsed the squash under hot water before peeling.

It was impossible to wash away this wax coating on my fingers, so I just left it on my hands even though it was annoying. After a day the wax was gone, but my fingers still felt tight and looked yellow for another day, most likely due to dermatitis.

Since then I'm careful to not rinse my butternut squash (or anything else covered in wax) under hot water. Instead I just give it a cold water rinse. I still get the dermatitis, but at least there is no wax!

I am a violinist and whenever I cut of butternut squash, my skin peels and is so tight that i cannot play. I didn't know how to get it off, but then my daughter came and told me to use packing tape. Surprisingly, it worked! A few peices of packing tape later, 90% of the it was off my hands.

This happens to me every time I make butternut squash. I am not sure what it is, but it comes off if you scrub it hard enough. I usually just take a sponge or something rough and scrub for like 5 minutes until its all off. Then I usually put lotion on afterwards. I am pretty sure it is not a skin reaction, its some kind of coating. Reading the other answers, I can't believe you guys leave your hands like that for days! I can't stand it!

the wax develops naturally from the sun. make sure the squash is fully ripe before handling and cutting/preparing. unripened squash have a chemical that can, and usually does attack the skin. Thats why unripened squash is usually fed to chickens or discarded.

I think its the wax. I took a box cutter and scraped most of it off. It felt horrible