But I'm at a healthy BMI already (and all things BMI)

No one can assign you a specific goal weight, not even you.

Your body has an optimal weight set point and we all sit on a bell curve of a natural human weight range. You are only healthy at your body's specific optimal weight.

There is no such thing as a healthy body mass index range, although we have all been told it is 18.5 to 24.9. Sadly, there is absolutely no science behind suggesting that that range offers maximum health benefits.

In fact the science suggests it is actually BMI 25-30 that offers the lowest incidence of illness and death.

For all the clinical data on body mass index, please read Women and Men of Substance