What does the cryptic crossword clue "Make less attractive men diet, needing ages to change (11)" mean?

The wordplay uses an anagram. anagram of MEN + DIET, + AGES = DEMAGNETISE The answer is DEMAGNETISE.

Make less attractive men diet, needing ages to change (11)

Times Cryptic #28902 | 6 Down | 2024-04-27 flower