While there is no such verb as "nawidzić", nienawidzić behaves as negated and therefore follows the usual rule of genitive(dopełniacz) with negations.
But as well as being the correct translation, "lies" is surely the idiomatic way to go. Not many people would say "I hate untruths", would they?
Though meaning the same, untruth(s) is often used as a euphemism for lie(s) in BrE conversational speech, because people often respond badly if directly accused of lying. The milder synonym fib(s) is used when speaking to young children.
In (British) Parliament, a political opponent may be described as being economical with the truth to avoid the "L" word which the Speaker of the House will admonish as "unparliamentary language".
In the 1970's Watergate Hearings in the US, the even more euphemistic terminological inexactitude was often heard, maybe to avoid provoking libel suits in that litigious country.