As much as advertising would have you believe that when you turn 30, you quit interacting with anybody other than your government-issued spouse and your hobbies narrow to leisurely jogging or preparing months in advance to do taxes, most people find that not much actually changes when they enter the new decade. Or so they think. In this thread on Twitter, people are revealing that while not all the ominous warnings they heard about aging are true, there are some of them that are, and they start early.
Here are some observations from people who are just reaching the big 3-0 and finding out what it has to offer, like the fact that even if you still feel like a teenage imposter in an adult suit, talking to an actual teenager will make you feel like your cultural literacy is a distant memory.

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People Human Interest
The Oregonian Public Safety
HealthDay
Mediaite
NBC Connecticut Entertainment
AlterNet
Daily Kos
The Week