What size

In my teens nothing bothered me,
Size 10 I could eat what I wanted,
My weight wasn’t something I worried about,

In my twenties and in my prime,
Size ten to twelve I watched what I ate,
Aerobics and weightlifting became my thing,
To keep my flat tum and tight bum,

In my thirties and two kids later now a twelve to fourteen,
My tum was bigger flabbier but not my bum,
I was always on one diet or another.

In my forties and now a size sixteen,
I have a big big tummy and slightly saggy bum,
Do I diet or exercise no not a lot,

Now in my fifties and a size !!!!!!!! eighteen,
I totally given up on the dieting,
With an underactive thyroid I dont see the point,
Now with a slight double chin and bingo wings,
Tum hanging low but bums ok it looks good in jeans 
I've not mentioned two things they flew south years ago.