Well, I posted this as a response to that blog, but I’ll also post here since my response is more specific to the question you’re asking.

Warning: LOGIC & SUPPORTING EVIDENCE INVOLVED

I have nothing against it, but I don’t agree that it’s necessarily healthy. 

Claim: masturbation increases risk for prostate cancer

(and potentially other health problems)

Supporting evidence here (all males should read this…you
don’t have to agree, but just know that there is evidence that supports
this). It makes sense because the development of the male sexual
organs, including the prostate, is dependent on levels of male sex
hormone…testosterone obviously. Athletes who take anabolic steroids
(chemically related to testosterone, which is really an anabolic steroid
naturally produced in the body – they have similar effects of causing
muscle and bone growth, but also share detrimental effects such as hair
loss) are at increased risk for prostate cancer…it’s not too hard to
believe that abnormally high levels of testosterone could put men at
similar risk.

Warning: Scientific discussion following…
I had a course where I learned something interesting about a type of
force (or tendency, if you will) known as sexual antagonistic
pleiotropy…much scientific evidence supports the idea that sexual
differentiation has a trade-off…gain genetic variation, but lose life
span and vitality, as the forces of natural selection are lost after the
reproductive age.

If you think about it, all animals have the
greatest vitality at reproductive age, but start to lose that vitality
after reproductive age, the reason being that natural selection favors
those who can produce an raise healthy offspring, but not necessarily
those who live the longest and healthiest, which is the reason that
after reproductive age, our immune systems slowly weaken, we are
significantly more susceptible to diseases, cancer, and we get all sorts
of age-associated problems as we grow older. 

Producing higher levels of sex hormones (testosterone for males, estrogen for females) is
indicative of greater sexual differentiation.  It is these hormones
that cause us to have our sex characteristics.  Males have higher levels
of testosterone and females have higher levels of estrogen.  Without
these hormones, male and female would be practically the same,
physically.  The same mechanism which drive our genders to be different
also cause us to expend “energy” (in the sense that our bodies put a lot
of effort into it) to make us most reproductively fertile, but evidence
*suggests* that it also has detrimental payoffs that manifest in the
forms of aging, cancer, and other age-associated problems.  Anyways, I
say that evidence points in this direction, but this is all not solid –
it is just what what it seems like, based on our incomplete knowledge.

I’m not trying to be negative… I just wanted to bring in another point of
view so this is not so one-sided because the facts listed under the
argument of masturbation being healthy comes from an extreme
over-simplification of the human body.  Also, I wanted to bring some
more logical points to the table, different from arguments with
arbitrary statements about the morality of it based on one’s own
religion (which is basically pushing one’s own religious values onto
others) or simply stating that it feels great which I imagine should be
common sense.

The human body is complex, so it doesn’t work to
oversimplify it.  Hormones are not either good for you or bad for you. 
Almost all mechanisms in the human body have some effects which are
beneficial to one aspect, but detrimental in another.  Painting
something as simply being “healthy” or “unhealthy” is a kind of naive
and erroneous way to think about it, in my opinion ;]

But yeah, all in all, take this with a grain of salt…I agree with most of the other things said in the post though.