It's whenever perimenopause begins for you. For some it's 35 (or earlier if medical problems), for some it's late 40's. For me it was late 30's.

When I was young I could eat a box of donuts and as long as I was in a calorie deficit I was good. Now it's hormones and macros and getting enough exercise - but not too much because if my cortisol levels rise I gain weight even if everything else is perfect. And I can't eat too little or my body thinks I'm starving and gains weight.

If it really was calories in vs calories out, I'd be 100 pounds.

If you're interested you can check out @drmaryclaire on IG. I honestly wish someone had prepared me. In fact my test results are only now showing I'm in perimenopause (I'm 44) even though I went through estrogen dominance years ago and other symptoms for the past 5 years or so. You're about to find out that the female body has not been studied so even doctors don't know wtf is going on with us or how to help us feel better. Dr. Mary Claire and others like her are trying to change that, though.