yes , in italian THE LIFE AND THE WAIST is the same word and the same pronunciation. you can differentiate them by topics , dipends on the context of the sentence. If i say only the word " LA VITA" i mean both meanings. COME VA LA VITA? or LA VITA E' PROPRIO DURA! LA TUA VITA E' MOLTO PICCOLA! or QUANTO MISURA LA TUA VITA?

Yes "vita" can be uset to express both "life" and "waist". However, in Italian we often use "girovita" to express both "waistline" and "waist", i think that "girovita" can be used to avoid the misunderstanding. "Hai una vita sottile" = "Hai un girovita sottile" both are correct, though the second is more immediate to understand