Can shampoo really repair hair? Experts debunk common myths.

For many, hair is the silent thermometer of well-being. It reflects both the body's internal rhythms and the external habits that surround it. However, a tangle of beliefs has grown around its care that, rather than strengthening it, actually weaken it.

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From daily shampoo use to the supposed miracles of natural products, myths abound that confuse more than they guide. Understanding the true hair cycle, its nutrient availability, and its relationship with stress, climate, and diet is key to stopping relying on unsupported homemade formulas and starting to make informed decisions about your hair's health and maintenance.

Cold water and shine

Two trichologists consulted by the BBC pointed out that it's not true that using ice water makes hair shiny. In fact, the care factor lies in how the scalp is protected from heat, chemicals, and environmental conditions.

However, this does not mean that you should wash with water that is too hot, as it can dehydrate you.

Magic formula?

The experts explained to the media that no product can repair damaged hair. In fact, the only solution is to cut it.

"Market products act as a kind of glue that binds hair together so it looks better. Don't be fooled into spending a lot of money on products that promise a solution," she said, noting that haircuts don't accelerate growth.

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There is no self-cleaning

This is a belief that hair cleans itself, allowing you to wash it infrequently or not at all. However, this claim is false.

"The scalp has 180,000 sebaceous glands and accumulates dirt and debris if not washed regularly," the experts noted, adding that not washing it can cause unpleasant odor and worsen scalp conditions like dandruff.

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Dry shampoo

This type of product is no substitute for washing. While it's a good alternative for improving your hair's appearance, the problem arises when it's used for several days in a row without rinsing.

"The scalp's natural oil absorbs into the shampoo, and yeast feeds on that buildup. If you're not careful, you'll end up with an itchy, flaky scalp," they emphasize.

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