No one said it did. It is however very addictive, causing addicts to smoke/vape more, thus increasing the load of the other toxic and carcinogenic substances.
Wikipedia does raise some concerning points about nicotine:
> Although nicotine is classified as a non-carcinogenic substance, it can still promote tumor growth and metastasis. It induces several processes that contribute to cancer progression, including cell cycle progression, epithelial-to-mesenchymal transition, migration, invasion, angiogenesis, and evasion of apoptosis.
Wikipedia does raise some concerning points about nicotine:
> Although nicotine is classified as a non-carcinogenic substance, it can still promote tumor growth and metastasis. It induces several processes that contribute to cancer progression, including cell cycle progression, epithelial-to-mesenchymal transition, migration, invasion, angiogenesis, and evasion of apoptosis.