I have spent decades reading up about the body and weight gain. Blood sugar, insulin response, metabolism etc
I first gained weight age 13 when I grew past my mum and aunties who told me I was fat. I was a size 10 to 12 until I started gaining and was a size 16 at age 13 due to comfort eating.
It really affected me and lead to an eating disorder. That I no longer have preferring to be fat than to have bulimia. (Well hit rock bottom in late teens and early twenties after multiple feelings, stomach pains, bad it's and really in ill health due to bulimia.) Hg and vomiting 50 times a day literally also cured me of bulimia never wanting to vomit ever again. Laxative use was painful and also stopped.
However my auntie projectied onto me how they felt about weight and their insecurities and we're naturally size 6 and size 8. One had two kids and was now a size 10 and always going on about it. My mum would show me her size 6 trousers and lament not being able to wear them.
Also tell me that a size 10 now was a old size 14 etc. They also did not have the large boobs I got naturally, my first bra was a c cup. Like my 10 year old daughter. Big boobs make you look bigger.
They didn't consider that we are all different and I was not meant to be small and petite like them. The other side of my family were all much taller with curves and I fell into the middle 5 foot 6 and not under 5 foot 2 like them or 5 8 or 5 9 like the other side. Most of that side are under 5 foot.
This period of life affected my metabolism and it has never recovered. I eat much healthier now and I cook from scratch sometimes and I exercise when motivated and able.
However my family like the fat shamers on this thread are so sanctimonious and they act like they are doing a fat person a favour.
Believe being left alone to live a good life is doing a fat person a favour and they will get healthy when they are ready and able to.