Does Having Dirty Hair Really Make It Grow Faster?

When it comes to maintaining strong and healthy hair, a regular wash and care routine is essential. In addition, things like letting freshly washed hair air dry, getting a trim, cutting down on chemical hair treatments, and using a heat protectant before styling can also strengthen your hair fibers and stimulate hair growth (per WebMD).

In fact, even though not washing your hair regularly might go against the grain, having dirty hair doesn't come entirely without perks, according to Erica Colon Makeup Artistry. For starters, unwashed hair makes hair styling much easier because the greasy accumulation of the hair's natural oils and product buildup gives the hairstyle a better hold. Additionally, having your hair strands a bit dirty right before a coloring treatment could protect your scalp from harsh chemicals and make the process less uncomfortable, explains L'Oréal Paris. So, if some sort of buildup can outshine clean hair in a few ways, does going greasy make your hair grow faster too? Here's what we know so far.

Turns out, dirty hair doesn't help with hair growth, celebrity hairstylist Kim Kimble tells Byrdie. If anything, prolonged periods of not washing can cause grime, impurities, and bacteria to accumulate on the scalp and clog pores, making your hair more vulnerable to breakage and leading to odor. Keep in mind, when bacteria grows on your scalp, it can cause irritation and diseases, accelerating hair shedding and hampering any hair growth attempts. If you have an oily scalp, for example, be sure to give it a good rinse every day or every other day with a balancing shampoo (per Sunday Edit). Those with dry textured hair, on the other hand, who are concerned with the idea that shampooing will dry out their hair even more, can wash it once a week using a moisturizing shampoo.

"Your washing routine does not negatively impact your hair growth," explains trichologist and founder of Colour Collective Kathy Yates to Sunday Edit. However, the scalp should be treated with the same consideration you give your face. Just as it is normal to wash your face and body every day, it doesn't hurt to cleanse your scalp daily. It's best not to go a long time between hair washes and still expect positive hair growth. Between the washes, tend to your scalp by giving it a good massage or coating your hair strands with a nourishing conditioner. In other words, a nice clean scalp is also essential for hair growth. 

To make your hair grow faster, start by choosing the right shampoo. "Pumpkin seed oil, yucca root, and saw palmetto are my favorite ingredients for promoting hair growth," says hair loss surgeon Dr. William Yates via Real Simple. In fact, due to the hampering of hair loss and stimulating hair growth, pumpkin seed oil extract and saw palmetto, in particular, are especially recommended by Yates. This is because the two ingredients reduce the effect of enzyme 5-alpha reductase, which converts testosterone to dihydrotestosterone (DHT), a hormone responsible for causing hair loss in men. Meanwhile, an anti-inflammatory ingredient with a high concentration of saponins, like Yucca root, can promote hair growth while relieving an itchy scalp.

In addition, a scalp massage with hot castor oil that is filled with antibacterial and antifungal properties can also stave off scalp infections and boost hair growth at cellular levels (per Byrdie). However, unhealthy lifestyle habits are the culprits of poor hair health and limited hair growth. Smoking, for instance, can eventually limit the oxygen and nutrients needed for an overall healthy mane, hair restoration surgeon Alan J. Bauman tells Byrdie. The toxins from smoking can hamper follicles and growth. To accelerate hair growth, stop smoking. Hair loss can also be brought on by certain medications, including some antidepressants and antihypertensives, among others. If you're having a hair loss problem, consult your healthcare provider to see if you can come off these medications.