Let’s talk about what ingredients to avoid in hair products!
Unfortunately, so many hair products contain harsh chemicals that have nasty side effects when used over time – even high-quality professional brands. 😱😱😱
So do you really know what’s in your shampoo?
I’m not gonna lie… it might even freak you out a little.
When I originally started this post, it took me about two months to finish writing it; it was so hard to learn the cosmetics industry’s evil truths.
But are you ready to find out what they are? Let’s dive into some of the absolute worst ingredients in hair products!
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#1: Polyethylene Glycol (PEG)
The first ingredient that you should avoid is Polyethylene Glycol or PEG for short. Let’s just start by saying that this ingredient can also be found in oven cleaner.
Common side effects include liver and kidney damage, birth defects, decreased sperm counts, and early breast development in girls and boys.
It can even cause premature aging of the skin if used over time and can leave the skin open to disease and bacteria.
#2: Dioxins
Dioxins aren’t usually listed in the ingredients, but they’re often present with emulsifiers, PEGs, and sulfates.
These nasty little things “literally modify the functioning and genetic mechanism of the cell, causing a wide range of effects, from cancer to reduced immunity to nervous system disorders to miscarriages and birth deformity.
“The tiniest amount can cause damage, and our bodies have no defense against it. The most visible example was Yushchenko, the new Ukrainian President, who suffered from dioxin poisoning and seemed to age overnight.” (RedFlag Skincare Toxins to Avoid)
#3: DEAs, MEAs, TEAs
DEAs (diethanolamine), MEAs (monoethanolamine), and TEAs (triethanolamine) are super common in shampoo. You can usually find them labeled as Cocamide MEA/DEA or Lauramide DEA.
Studies show that repeated skin applications of DEA-based detergents majorly increased liver or kidney cancer chances in animals and can likely cause cancer in humans (kids may have a greater risk).
They can disrupt chemicals in the body and form cancer-causing nitrates and nitrosamines.
TEAs balance pH levels but can cause allergic reactions, eye problems, and dry hair. They’re also toxic when absorbed into the body over time.

#4: Propylene Glycol
Propylene Glycol is a surfactant, solvent, and wetting agent. This ingredient breaks down protein and cellular structures in other chemicals.
…which as you can imagine, damages the protein in skin and hair, causing premature aging.
In fact, workers must wear protective gloves, clothing, and goggles when working with this chemical in industrial settings; exposure can cause brain, liver, and kidney abnormalities.
#5: Sulfates
Sulfates are the main cleansing agents found in shampoo and one of the worst ingredients for your hair’s health.
These nasty chemicals come from the salt of sulfuric acid. The most common sulfates found in shampoo are:
- Sodium Laureth Sulfate(SLS)
- Sodium Lauryl Sulfate(SLES)
- Ammonium Laureth Sulfate(ALES)
- Ammonium Lauryl Sulfate(ALS).
Detergents and surfactants pose serious health threats; they’re found in engine degreaser, car washes, garage floor cleaners, dishwashing soap, and in 90% of products that foam.
You can even often find SLS and SLES in conditioner.
The American College of Toxicology states that sulfates “cause malformation in children’s’ eyes” and have “a degenerative effect on the cell membranes because of its protein denaturing properties.”
They also added that “high levels of skin penetration may occur at even low use concentration” (source).
Other research indicates that it could cause immune system damage, causing layers to separate, inflame, and age.
SLS is not a carcinogen, but since it causes severe epidermal changes to the area it is applied, it can increase the risk of cancer.
There are significant correlations between SLS and contact dermatitis, which can cause reddening, soreness, or inflammation of the skin.
Other side effects include eye damage, depression, labored breathing, diarrhea, severe skin irritation, and even death. ALS and ALES are similar but more water-soluble.

#6: Isopropyl Alcohol
You probably know that hangovers are caused by dehydration, right?
This is because alcohol inhibits the kidneys’ anti-diuretic hormones, which leads to an interruption of the body’s Krebs cycle and causes swelling of the brain against the lining of the skull (Wikipedia: Hangover).
On the same token, rubbing alcohol can be used to absorb spilled water on a phone or computer.
So can you imagine what it does to your hair and scalp?
Lack of hydration is a main contributing cause to hair damage… yet, we massage alcohol into our hair and scalp every day in the shower…
Isopropyl alcohol is a petroleum-derived substance in antifreeze, a wood finish, and even a solvent found in shellac.
Side effects include headaches, flushing, dizziness, mental depression, nausea, vomiting, anesthesia, and even coma in the worst cases. The fatal ingested dose is less than one ounce.
Instead, look for hair products with good alcohols like:
- Cetyl alcohol
- Cetearyl alcohol
- Stearyl alcohol
- Lauryl alcohol
💡TIP: Love, Beauty & Planet is an inexpensive shampoo/conditioner line that uses the good alcohol.
#7: FD& C Color Pigments
Manufacturing companies add synthetic colors to shampoo and other hair products to make them visually appealing. They’re typically more concerned that their product is the perfect shade of pearly pink than the adverse health effects behind it.
Almost all synthetic colors contain coal-tar, which is a known carcinogen.
Furthermore, the absorption of specific colors will deplete the body’s oxygen supply and can even cause death in some rare cases.
On a smaller scale, these dyes also contain heavy metal salts (which isn’t an 80’s hairband) that deposit toxins in the skin and can cause major irritation.

#8: Parabens
You’ve probably noticed that many products advertise being paraben-free on their packaging.
Even though I didn’t know what parabens were initially, I could have guessed that they weren’t good.
So here’s the deal… parabens are a class of fungicidal and bactericidal chemicals… and they can also be found inside breast cancer tumors.
These chemicals mimic estrogen (the primary hormone involved in breast cancer), which can also lower puberty age in girls and cause other hormonal disruptions.
Finally, parabens may also cause premature aging if used with UVB light… which is awesome since many tanning lotions have parabens in them.
Common types of parabens found in hair products:
- methylparaben
- ethylparaben
- propylparaben
- butylparaben
💡TIP: Just avoid them altogether! Look for a quality paraben-free product like Verb Hydrating Shampoo!
#9: Fragrance
Good luck trying to find a shampoo that doesn’t contain fragrance.
The thing is… a lot of people choose products based on how good they smell. In fact, I kind of always thought it was weird that people looked for fragrance-free products.
But guess what? Certain fragrances, known as “phthalates” are known to cause cancer.
Did you know that phthalates have been banned in certain areas (like California) since they are known to cause birth defects, liver cancer, and hormonal disruptions?
On top of that, headaches, dizziness, rashes, skin discoloration, violent coughing, vomiting, and allergic skin irritation have all been reported to the FDA with exposure.
Clinical observation has shown that fragrance exposure can affect the central nervous system, causing depression, hyperactivity, irritability, or other behavioral changes.
💡TIP: Try adding essential oils to unscented products for a natural, healthier option.

#10: Ureas and DMDM Hydantoin
Did you know that most shampoos have formaldehyde in them?
You should definitely try to avoid ureas and DMDM Hydantoin… but unfortunately, they’re in everything.
Urea chemicals often come as Imidazolindinyl urea, and its brother, Diazolidinyl urea.
Have you noticed that the word urea sounds similar to urine?
It’s not a coincidence. Urea is the main nitrogen-containing component of urine in mammals.
The good news is that the ureas found in hair products are synthetic… and not harvested from porta-potties, thank God.
The bad news is that both ureas and DMDM Hydantoin are formaldehyde-releasers.
Formaldehyde in Hair Products
These ingredients are added to cosmetics as preservatives; they’re meant to kill bacteria.
However, formaldehyde is a known carcinogen and comes in other names like Quaternium-15 and Bronopol. The FDA deems these ingredients safe in small doses, but several other countries have banned them.
On top of that, formaldehyde is a “volatile organic compound,” which means that it can become breathable gas under warm, wet conditions (like in the shower). It irritates eyes and respiratory systems, causes heart palpitations, and inflammation of the skin.
Exposure to formaldehyde can also cause joint pain, allergies, depression, headaches, chest pains, ear infections, chronic fatigue, dizziness, and sleep loss.
It can aggravate coughs, colds, and trigger asthma.
In serious conditions, it can weaken the immune system and cause cancer.
FAQ

Formaldehyde, parabens, sulfates, fragrances, artificial color, and alcohols are all ingredients to avoid in hair products.
Alcohols, sulfates, and parabens are some chemicals found in hair products that can dry the hair and cause hair loss.
Sulfates are harsh detergents that strip the hair’s natural oils and dry it out, leading to damage and hair loss, among other side effects.
Final Thoughts

Most of us are entirely unaware of the dangers lurking in our everyday products. Unfortunately, hair products and cosmetics are no exception to this.
The good news is that most of these ingredients are safe to use in small amounts. However, it’s still always best to avoid them when you can.
It’s becoming more common to see products formulated without these ingredients, so keep your eyes peeled.
Until next time,

Your Turn: Do you know of any other ingredients to avoid in hair products? Have you ever had any reactions to these chemicals? Drop your thoughts in the comments section below! 👇🏼👇🏼👇🏼
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Timantha
Friday 19th of February 2021
Why is bat poOp in mascara??? I was wandering if you knew that???
Vicki
Tuesday 4th of August 2015
So give us a list of recommend hair products that don't contain any of those things...
kanesha
Monday 20th of October 2014
Thanks for posting. This was very helpful.
Lavoire Beauty Co.
Wednesday 30th of October 2013
Great list. Thanks for posting this information.
Wednesday 10th of July 2013
this stuff can be scary