Yes, deodorant is safe to use.
Changes to hormones, sweat and oil glands during puberty cause armpit smell changes. Wearing a clean shirt and washing armpits every day can help people feel and smell healthy. Some people use deodorant, which “covers up” the smell, antiperspirants which cover up the smell and stop some sweating or baking soda which absorbs some of the moisture and smell. Talk to your parents or health care provider about what products might be right for you.
The Canadian Cancer Society has never found proof that deodorant or antiperspirants increase the risk of cancer. Using deodorant or an antiperspirant is a personal choice.