IPA: /ʌnˈhoʊlsəm/
KK: /ʌnˈhoʊlsəm/
Something that is harmful to health or well-being, either physically, mentally, or morally.
Eating too much junk food can lead to unwholesome habits.
Unwholesome → It is formed from "un-" (meaning not) and "wholesome" (from Old English "hal" meaning whole or healthy, and "some" meaning characterized by). The word "unwholesome" means not characterized by health or wholesomeness.
Think of 'not' ('un-') being added to 'healthy' ('wholesome') — that's why unwholesome means something that is not healthy.