Oh, to give an alternative bent (since being alternative is my specialty). . .I have found regular fasting to increase vascularity all around and libido in myself.
That's a research study of 1 subject - me - totally unblinded, unscientfic, and unfunded by a pharmaceutical co., lol.
However, there is some good research indicating fasting elicits a secretion of growth hormone.
HGH (Human growth hormone) is a "youth hormone" with broad reaching consequences (all hormones are potent - many of these exist in the blood at 1 ppm and cause all kinds of changes).
So. . .there is some intellectual sense to indicate that humans who engage in some regular fasting are reversing the aging process somewhat internally (doesnt' cause wrinkles or gray to go away). And let's face it - youth = libido.
If you aren't insulin dependent diabetic or some other contraindication, I do recommend periodic fasting to my patients.
But then again, chiropractors are always a bit kooky and quacky. You either dig us or hate us.
Here is my website (also co-authored with a nephrologist): Fasting Basics: Your Guide To The Practice of Fasting
Haven't worked on it in ages - one of the things on my "To-Do" list.