I have two 40's babies, I m very active and don't feel old at all. For years I thought I was obese, due to my health club saying at 141 lbs and 5'2" I was at 26 BMI. Last week weighed myself on a friend's scale, it had BMI on, mine was 15.9! I am relieved I don't have to worry about weight, my doctor always says I'm fined, it's off for short people.
I can go out today and run a 5K, or go skiing on the blacks, or stay up late. I listen to the radio with my kids, and keep up on some trends. My blood pressure is low, usually about 122/65.
Two ways I know I'm older- it's easier to nurse these babies, gravity has a few good effects! and sometimes I had to get out a knife and pound on the itty bitty baby food lids to open them. If that's the worst I have to deal with, I'm very happy.
Dh is on blood pressure meds, he has more physical signs of aging, I think. He is more tired.
I hope I have lots more years, you never know, but in the meantime I feel very healthy and young at heart.
VNW, I've been on synthoid for 12 yeaars, the only bother is not eating for an hour, although I do have coffee with creamer, probably not supposed to, but I have for years, decaf with coffemate flavored creamer.