So my Boyfriend has gained a lot of weight

Okay so girls ...

I love my boyfriend wholeheartedly! He is the most amazing, loving man that i hope to spend the rest of my life with.

We've been together for over a year now and everything is pretty good but his confidence has gone down quite a lot cause he has gained a lot of weight ..not a lot a lot to a point where he has a big tummy and rolls or anything but he's just chubby which is not too bad cause he's very tall so to me its okay...

Well i thought it was okay until recently I'm realising that as much as i love him im not too impressed by it. He still turns me on and i still love sleeping with him but he's weight is not exactly impressive too me as much now ..

What should i do?? Or what is the best way to address this without knowing his convidence?