Age is like wine or cheese, it only gets better

Age is something that is brought up almost daily in Japan. It makes me feel like I have some sort of expiration date; as if my quality will steadily decline with age. Upon questioning why it's so important, I was told it is important for people to know how old you are in order to know how to act towards you. I am 26 years old. What does that mean exactly? How should people act towards me? Maybe the better question is how should I act? I'm past the winding forest of a teenager and over the party hill of my early twenties. I wonder if there is a chart somewhere that says how people should act when they're a certain age. I asked the one source that has all the immediate answers: Yahoo. I discovered that there are other people out there that asked the exact same question as me. HA! I knew I wasn't the only one. Perhaps that's what 26-yr-olds do, ask questions. So here is what one entry said:

QUESTION: How Do You Act Like A 26 Year Old? I know this sounds like a dumb question, but I'm not sure where I should be at this point in life or how I'm expected to act. Anyone older than 30 that could tell me what the difference between 26 and your 30s is?
ANSWER: 25/26 is about that age all your friends have moved away or are getting engaged. Thats also the age you should start making some big risk taking moves with your life. By time your 30 you really should be in a career and the older you get after 30 the less risk you can take and the less options you have.
You should be in a job and looking for a marriage-track relationship. You are expected to have some control of your emotions and consideration for others. You should remain positive. Your dress and hairstyle should match "normal" people of your age. [Maybe I should take notes and read lots of magazines?] You probably should start phasing out cartoons, comics and teen-oriented music. [Btw Japanese young and old are in love with cartoons (anime), comics (manga) and teen music (J-Pop). ]

Basically what I learned from my online research is that 1) Efficiency of my organ systems begins to diminish at the rate of about 1% a year after age 20 [I am dying after age 20] and 2) People should try to be like everyone else their age and that is how one knows how old they are. But do I really want to act like everyone else does just to satisfy my age litmus test? I think Yahoo Answers captured what most people in America think about 26-year-olds. But somehow that answer doesn't satisfy me.