Healthy eating is easy for me.

What gets eaten at nine in the evening was decided on Saturday morning in a supermarket, by a calmer person with different priorities and more time.

Ease here is rarely willpower. It is logistics. The nine o'clock version of anyone is tired and has no interest in chopping anything, and expecting that person to negotiate is a design problem rather than a character one.

So the useful question is not how to be more disciplined at nine. It is what the Saturday person could leave in the fridge, already washed, at eye level.