The word healthgiving means something that promotes health or has a beneficial effect on the body or mind. Antonyms for this word would therefore be terms that have a negative impact on one's health, both mentally and physically. These could include words such as harmful, damaging, and unhealthy. Other antonyms could be substances or behaviors that are addictive, such as alcohol or drugs, or lifestyles that involve poor diet, lack of exercise, and stress. Essentially, anything that stands in the way of good health could be considered an antonym for the word healthgiving.