Which hair treatment is best for naturally curly hair seeking to reduce frizz?

A smoothing treatment is the best choice for naturally curly hair that aims to reduce frizz. This type of treatment typically involves the application of products that seal the hair cuticles, making the hair smoother and reducing the likelihood of frizz caused by humidity and environmental factors. Smoothing treatments often use ingredients like keratin or amino acids, which help to enhance the hair's structure and provide a sleek appearance.

While the other options may offer benefits for different hair needs, they do not specifically target frizz reduction in naturally curly hair. A volume perm adds curls and texture rather than smoothing, hair gloss provides shine but does not necessarily reduce frizz, and a texturizing treatment is used to enhance waves or curls rather than to control frizz. Therefore, a smoothing treatment is clearly the most effective choice for addressing the specific issue of frizz in naturally curly hair.