First I need to justify my usage of the term "youth" - having reached the "age of reason", I have the perspective of the years to make valid (i.e. experiencially substantiated) comparisons. That is all. And now to the topic at hand.
I have always felt this to be true, as when observing teen dynamics or some of my young university collegues who are still in their early twenties. In the latter case, usually when a group engages in a discussion of even something remote and theoretical, what seems to dominate is the character of the delivered statements, not their content alone. Nicely wrapped and eloquently delivered packages, with suprisingly average content. This is not an evaluative statement, merely an observation; it appears that we tend to learn how to send envelopes, before we learn what they should contain.
Last week, as I was leaving a train station, and upon approaching the stairs leading down to the underpass I noticed a group of four 18-20 year old women. One of them slipped on the wet stairs (as it was raining earlier), and as she landed on her backside - which looked quite painful - I was amazed how she started laughing unnaturally and nervously, obviously giving her girlfirends a sign that nothing had happened. Fiercely blushed cheeks however, betrayed her embarassement. Her social status as a "non cluts" was more important (and of immediate value) to her than her physical wellbeing, apparently. You don't see this kind of behavior equally prevalent in adults or the elderly. I can imagine fear in their eyes in such situations, if anything.
Why this apparently irrelevant embarassement in cases of small, physical danger? Embarassement is certainly an unpleasant sensation. It is a hormonally induced state telling us "you look less attractive (i.e. less fit)". Since our social bonds are fundamentally being shaped and often established in our youth, and also due to the fact that this is the peak of our sexual activity, it is imperative that we project an image of a fit, healthy, socially sophisticated and mentally capable individual. Embarassement tells us when we fail to maintain that image.