If weight loss is simply cals in / cals out, why do post menopausal women have a harder time losing weight?

Question

Same goes for older people in general. Is it harder to lose weight because they simply move less? What’s happening that makes weight loss so much harder in 30s and above?

In: Biology

Answer 1

Your body is composed of an ecosystem of many different critters, all of whom are eating different stuff, and pooping different stuff. ‘calories in’ is only calories if something in your gut eats it. Same for calories out. The idea that we are a single organism that consumes and burns calories is just wrong. So no two people will get the same calories from the same meal, or burn the same calories working out.