Boyfriend slacking on hygiene and self image?

I’ve been with my boyfriend 3 years. When we first started dating he was fit, carried himself with confidence, and had perfect hygiene. 3 years later he’s gained about 30 pounds, slacks off on hygiene, and doesn’t have that boost in his step anymore. Also he’s 19 it’s not like he’s an older male. I’ve kept myself up, if anything I look better now. it’s getting to where it’s turning me off...I’ve tried to hint to him what should I do?