Source : WordNet®

unhealthy
     adj 1: not in or exhibiting good health in body or mind; "unhealthy
            ulcers" [ant: {healthy}]
     2: detrimental to health [syn: {insalubrious}, {unhealthful}]
     3: not conducive to good health; "an unhealthy diet of fast
        foods"; "an unhealthy climate"
     [also: {unhealthiest}, {unhealthier}]

unhealthiest
     See {unhealthy}