See subject line. Body hair (in this case, the hair under my arms) is easier to pull out during a hot shower. Why is this?
I don’t have a factual answer, I just wondered if it’s possible that hair isn’t easier to pull out when wet; rather it’s easier to break when it’s wet; which would give the appearance of pulling out if it broke under or near the skin. In which case that makes sense as it’s widely known that hair is softer when it’s wet as is proven by the difference between dry shaving and wet shaving.
I was out on a film shoot one day where we had to stand in the hot sun for several hours on a very humid day. I rarely ever sweat at my underarms but this day I was. I noticed my underarm hair would come out with just the slightest pull. Kind of spooked me out.
If it is softer, then it is MORE difficult for it to break, because it is more pliable. To break more easily, you want something that is more brittle, not more soft.
If that’s the case, then it’s very consistently breaking off below the skin; there’s no stubble.
Perhaps it’s easier to get a good grip on the hair because the oil on it has been washed away, or because wet skin has more friction than dry skin.
Not correct. It’s not a matter of brittle vs. soft; those are two extremes for hair caused by different things. You can have very brittle, dry hair that is in no way made less brittle by having it soaking wet. (Nor, for the most part, by slathering goo on it. Moisturizers don’t really fix brittleness much.)
The caution against brushing your hair when wet is because water absorption weakens hair - a different process from being brittle. Being wet also increases the drag of the brush or comb. The result is that if you have brittle hair, it will tend to break easily. If you have wet hair, it will tend to break easily. If you have brittle, wet hair, it will break that much more easily.
If you think hair is pulling out, all you have to do is look closely to see if there’s any trace of the follicle on the end. None: it broke, possibly right at the scalp.