How to prevent my grey from developing a curved foot as he ages?

I've seen people on here discuss a potential issue African Greys can develop a curved foot from their perches, and I'm wondering what steps I can take to prevent it?

My grey has several perches in his cage, but at times he tends to favour a thinner branch that his feet curve around almost fully.

Is there are any steps I can take or things I can be aware of to prevent it becoming an issue as he ages?