Spraying a few drops of perfume on your hair before going out is part of many women's routine. The scent lasts longer, follows you all day, and leaves a pleasant sense of freshness. But that very common move can have a little-known effect on hair health - and it's worth knowing before it becomes a habit.

According to pharmacist Katrina Riera, the main problem lies in the composition of classic perfumes. "Most perfumes and colognes contain a high percentage of alcohol," she says. That alcohol "can dry out the fibrous structure of the hair, making it more brittle, coarser, and prone to breakage." And when perfume is sprayed close to the roots, "it can also irritate the scalp." Some aromatic compounds further sensitize the skin in predisposed people, but alcohol remains the main culprit.

So why do so many women do it? Because hair holds a scent much longer than skin - the strands act as a natural diffuser and, with every movement, release a little of the perfume's notes. Precisely because of that ability, more and more brands are developing special hair mists, designed to smell good without drying, often with ingredients that hydrate and add shine.

If you do want scented hair, the difference is in the product and the way it's applied. The best option is perfumes designed specifically for hair, applied "from the mid-lengths to the ends and from a certain distance, avoiding the roots and scalp." If you only have a classic cologne, there's a safer alternative: spray the perfume onto your brush, wait a few seconds for some of the alcohol to evaporate, then gently comb through your hair.

Alcohol harms some hair types more than others - the effect shows fastest on faded, dyed, dry, or heat-damaged hair. Curly hair also handles it worse. And three common mistakes: don't spray directly on the roots, don't apply several times a day, and don't perfume your hair right before a flat iron or blow-dryer. Heat and alcohol together are a recipe for dry, brittle strands. Sometimes the smallest habit carries the biggest cost - and no perfume seller will tell you that.