These Are The Worst Chemical Hair Straightening Treatments, According To A Doctor

November 7, 2016 by Lisa Fogarty
shefinds | beauty

Natural hair texture and even a bit of frizz may be en vogue this season, but that doesn’t mean chemical hair straightening treatments aren’t still in demand amongst many women. The allure of a smooth mane can not be denied, no matter what we’ve seen on runways–but at what cost? With so much controversy surrounding hair treatments like Japanese Thermal Hair Straightening, it’s natural to wonder and worry about the chemicals being used in these treatments and how they can affect our health.

Dr. Ken L. Williams, surgeon, founder of Orange County Hair Restoration and author of Hair Transplant 360, says relaxing the hair shaft can give you easier-to-manage curls, but it can also potentially damage both your hair and scalp–resulting in permanent hair loss in some cases.

“Chemical straightening or hair relaxers are in essence a reverse perm,” Williams says. “Instead of making straight hair curly, you are making curly hair straight by breaking the hair follicle’s disulfide bond. Disulfide bonds are the key factors in supplying the hair it’s strength and durability. Straightening hair is actually more damaging to hair then a perm because of the frequency of treatments. Straightening is done approximately every eight weeks, where as a perm is approximately every four months. The more often straightening of the hair is performed, the more overlapping of previously processed hair resulting in more damage and breakage.”

While relaxing treatments are damaging, if done correctly and the frequency of treatments reduced, they may actually be beneficial since they eliminate the need to use damaging tools such as flat irons, hot combs, pressing, and hot oils, Williams says. With that in mind, Williams reminds us that the chemicals used in relaxing treatments are very strong and must be applied at scalp level to have the desired effect. If done incorrectly, you can get chemical burns on your scalp, and this can result in infection, scarring and/or permanent hair loss–so it’s really important to visit a well-regarded stylist.

As for the chemicals you can expect to find, Williams says there are two basic types of hair relaxers: hydroxide, which contain lye, and thioglycolate.

“The main active ingredient in a lye relaxer is sodium hydroxide,” Williams says. “Sodium hydroxide relaxers are very effective in breaking down the hair’s bonds, which straighten the hair quickly. Because it processes quickly, it is also the most commonly used relaxers by cosmetologists. Through speedy and precise application, professional stylists are able to apply the relaxer evenly, process the relaxer in a timely manner, and rinse thoroughly with a neutralizing shampoo to avoid damage and potential irritation during the chemical process.”

As for the second option, which contains no lye and counts hydroxide as its active ingredients, Williams says this option is better for people with sensitive scalps because the chemicals and pH level of these types of relaxers are milder. Ah, but there is one catch.

“No-lye relaxers are commonly associated to dryer hair due to calcium buildup,” Williams says. “This can easily be addressed through the use of a clarifying shampoo to remove dull deposits and a deep conditioning treatment to add moisture back to the hair.”

Finally, no conversation about chemical straighteners would be complete without mentioning the F-word: formaldehyde.

Keratin hair straighteners or Brazilian blowout products are always a concern among experts because they contain formaldehyde, which is a toxic chemical ingredient, says Dr. Luz Claudio,  Tenured Professor of Department of Preventive Medicine.

“It can cause irritation to the skin nose and eyes and it is known as a sensitizer, meaning that it can trigger allergic reactions and asthma like symptoms,” Claudio. “It can also cause cancer when people are exposed to it for longer periods of time. One of the concerns that we have in the field of environmental medicine is that even products that are labeled as “formaldehyde free” can contain methylene glycol, which can release formaldehyde.”

If all of this sounds so scary you’re considering canceling your next salon appointment, peruse photos of your favorite models and celebs rocking natural hair and remember: if Cara Delevingne can feel the frizz, so can you.

For more hair tips, check out hair static 101 and are ponytails really bad for your hair? 

Follow me at @lisacfogarty on Twitter.



Beauty, hair


Lisa Fogarty is a lifestyle writer and reporter based in New York who covers health, wellness, relationships, sex, beauty, and parenting.

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