How long is a sim a young adult/adult?

"kiwi84;d-1005248" wrote:
I am trying to decide at what age a sim will go over to be an adult from young adult, and I think for me it would be about 40 years old. Only problem I feel like the sims make the adults look so much older than 40. How do you define the ages in sims 4?

In my own head canon, a YA is 18, since here in America Teens of this age were given the right to vote and to sign contracts. I also think of them as Adults at about 35 years of age. (Middle age, a life stage largely ignored would begin around 40-ish.) Elders become so at age 65, because that's when we're forced into using Medicare, for health insurance. I don't find the adults looking older than 40, they don't even look old. Trust me 40 is still quite young. I have a daughter and son-in-law and my oldest son all in their forties. None of them look old. What I find laughable is that the minute a Sim becomes an "Elder" suddenly they have gray hair and are all bent over! That's simply not the case for many of us. I have a few streaks of white hair, but I walk upright, as I always have. Yes, there are aches and pains, but it's all good. I may just have to change the color of the hair for some of my Sims. And I don't dye my hair, either. I refuse.

That being said, there are no real guidelines.