体重が増えて

has gained weight

→ 体重
phrase Rare #34,001
has gained weight The て-form of 増える (“to increase”), used to connect to what follows. With 体重, it naturally means that someone has gained weight.
JA: 最近、体重が増えてきた。
EN: I've been gaining weight lately.

体重が増えています。

I'm gaining weight.

また体重が増えてきたのかな。

I wonder if I’m starting to gain weight again.

彼は以前よりもずいぶん体重が増えている。

He has gained a lot of weight compared to before.

急に体重が増えてきちゃったんだよ。

I've suddenly started gaining weight.

彼は体重が増えている。

He is gaining weight.