Nothing is always healthy, and I question any attempt to deem something unnatural. Such arguments inevitably lead to senseless moralizing.
Does a man who films himself masturbating degrade himself? How about male porn actors - do you assume that they do it because they don't have alternatives?
A large number of men and women like BDSM, as part of a healthy sex life - is that unnatural? Degrading? Tons of couples film their own porn... why are women assumed to be passive in that decision?
This is a classic second vs. third wave disagreement. Your assumptions are based on an understanding of women that is nearly obsolete. No offense, really, I just think that perhaps your opinions are informed by experiences that took place many moon's ago, and haven't really accounted for how things have changed. Many of the new generation of female pornstars do it because they want too, not because they need too.