Agree with the posters who say "don't worry about sizes" it is eating healthily, keeping active and testing whether we are overweight (fat is an unhelpful word) against the medical criteria, nothing else.
I am 64, love my food and having always struggled with my weight - increasingly as I age.
Got to my heaviest earlier this year at 15:5 (5ft 5in). Woke up one morning and decided drastic action was required.
Now on 800 calories a day (anything more than that and I simply do not lose weight!) fully supported diet - not a fad - and I have lost 2 stone now. Aiming for another stone at least, probably 2.
However, am aware that as I am older, losing too much can leave you haggard and with the dreaded saggy skin, so taking it all a stone at a time!
Can now get into size 14 which is thrilling for me! So I find it genuinely distressing to see posters talking about anything over a 12 as being "fat", even at 6ft!! That is ridiculous. It may/may not be overweight, depending on your shape and where you carry your weight, but that should not be a matter of subjective self-assessment!!!
People talking about how the sizes have changed have lost sight of the fact that a good part of this is because modern women's frames have changed, not just their weight. Women are taller and broader in their bone shapes than historically.
I am an hourglass shape and I would have to be very light indeed to get into some sizes as my hips (bone not fat) are quite wide, no matter my weight. I am lucky in that I don't carry my weight on my middle.