The word "pure" is critical. In an age where "nude content" is algorithmically linked to adult entertainment, pure nudism distinguishes itself through intention.
There is a biological logic to "skin hungry." Natural sunlight on the skin synthesizes Vitamin D. The absence of restrictive clothing lowers cortisol (stress hormone). The feeling of wind or water over the entire body triggers a somatic release that clothed swimming cannot replicate. Pure Nudism