Hello Johnny,
Given that each product is intended for completely different cleaning
tasks - one is for treating dandruff, one is for cutting through
grease and oils on dishes - determining which is best is largely
dependent on what you want to do. Both will clean your hair equally
well, but Dawn won't treat your dandruff. Denorex will take care of
your dandruff, but Dawn will do a better job of getting oils out.
Each has its own cleansing advantage, so we're left to look at which
is more harsh.
Looking over the ingredients, each has potential to be drying (due to
the surfactants), but it would seem that the addition of conditioning
agents to the Denorex give it a slight edge over Dawn in the "not as
drying" department.
I went back to previous answers for the ingredient lists:
***Denorex Advanced Formula***
Active Ingredients: Pyrithione Zinc 2%
Inactive Ingredients: Citric Acid, Cocamide MEA, Cocamidopropyl
Betaine, FD&C Blue No. 1, FD&C Yellow No. 5, Fragrance, Glycol
Stearate, Magnesium Aluminum Silicate, Menthol,
Methylchloroisothiazolinone, Panthenol (Pro-Vitamin B5),
Polyquaternium-10, Propylene Glycol, Purified Water, Sodium Laureth
Sulfate, Vitamin E, May Contain Sodium Hydroxide
Chemicals
http://answers.google.com/answers/main?cmd=threadview&id=149134
***Dawn, Original Formula***
water, sodium lauryl sulfate, sodium pareth-23, sulfate C-12-14-16,
dimethyl amine oxide, SD alcohol, undeceth-9, propylene glycol,
cyclohexandiamine, polyacetate, protease, fragrance, FD&C blue, no
phosphate
Non-Ultra Dawn
http://answers.google.com/answers/main?cmd=threadview&id=219255
So, what do we know about these ingredients? Both products contain
propylene glycol, a humectant (a product which promotes moisture
retention):
"Propylene Glycol - Combination of glycerin and water, an organic
humectant similar to Butylene Glycol used in cosmetics. Clear,
colorless liquids that are among the most common moisture-carrying
vehicles in skin care. It delivers superb permeation through the skin
and excellent humectant properties (softens and moisturizes the
skin)."
Make Your Own Cosmetics Glossary
http://www.makingcosmetics.com/makingcosmetics/glossary/16_glossary_p.html
Both contain fragrance and dyes (neither of which do more than make
the product look and smell nice), and both contain water and
thickeners to improve pourability.
What about the "rough stuff"?
We know that both Sodium Lauryl Sulfate and Sodium Laureth Sulfate are
surfactants - cleansing agents - of debateably varying degrees of
harshness:
"Lauryl sulfates (sodium lauryl sulfate, triethanolamine lauryl
sulfate, ammonium lauryl sulfate) are found in most shampoos as the
main surfactant since they work well in both hard and soft water,
produce rich foam, and are easy to remove. This group produces good
cleansing but is hard on the hair.
Laureth sulfates (sodium laureth sulfate, triethanolamine laureth
sulfate, ammonium laureth sulfate) produce rich foam, provide good
cleansing, and leave hair in good condition. They also are a common
main surfactant."
eMedicine - Hair Cleansing
http://www.emedicine.com/derm/topic508.htm#section~hair_cleansing"
Dawn also contains undeceth-9 and dimethyl amine oxide, non-ionic
surfactants commonly used in shampoos *and* dish detergents.
Undecth-9 is specifically recommended for cleaning up oil:
"Excellent choice for hard surface cleaning, particularly oily soils"
Tomadol 1-9 (CTFA Name: Undeceth-9)
http://www.tomah3.com/products/show.asp?ProdID=117
Though this alone would make it appear that Dawn is harsher, the fact
is, there are more surfactants in the Denorex, one of which is known
to cause excess drying and "contact dermatitis":
**Cocamide MEA - a surfactant derived from coconut. Makes shampoo
foamy
Specialty Surfactants
http://www.alzointernational.com/surfactants.htm
"Cocamide MEA (from coconut)"
Skin and Hair Care
http://www.greatplainsgifts.com/Skin_zg_Hair_Care.html
**Cocamidopropyl Betaine - a surfactant. A foaming agent and foam
liquid stabilizer.
Cocamidopropyl Betaine
http://www.chemistrystore.com/cocamidopropyl_betaine.htm
Cocamidopropyl Betaine appears to be linked to some cases of "shampoo
dermatitis", a condition in which the scalp becomes dry and irritated:
"The dermatitis cleared up after she changed to another shampoo. We
diagnosed her condition as an allergic contact dermatitis from
cocoamidopropyl betaine and lauryl dimethyl aminoacetic acid betaine."
Case report: Shampoo dermatitis due to cocamidopropyl betaine and
lauryl dimethyl aminoacetic acid betaine
http://www.med.nagoya-u.ac.jp/Environderm/edj/vol7/71-1600.htm
Where Denorex claims the slight advantage is in the conditioning
agents.
Dawn, being manufactured with the intention of getting your pots and
pans clean, doesn't concern itself with conditioning agents - its
strong points are non-ionic surfactants undeceth-9 and dimethyl amine
oxide, as well as amino acid protease for getting rid of the grease on
your dishes. It doesn't concern itself in the slightest with keeping
your hair from drying out (but does concern itself with your hands -
propylene glycol keeps your skin soft).
Denorex, on the other hand, is specifically made to be used on hair.
It needs the surfactants to clean, but just to make sure that your
hair retains moisture, it contains some conditioning agents
*specifically* meant to keep your hair happy:
**Panthenol (Pro-Vitamin B5) - a "pro-vitamin", used as a moisturizing
agent.
"D-Panthenol is the most used pro-vitamin in the cosmetics industry.
Because of its physical properties it is easily incorporated into all
normal cosmetic formulations. It is penetrates the skin, hair and
nails and generally fulfills all the expectations of both the producer
and consumer."
Panthenol
http://www.roche.com/vitamins/pdf/dpanth.pdf
**Polyquaternium-10 - a conditioning agent
Functionalities of Amerchol Conditioning Polymers at a Glance
http://www.dow.com/amerchol/overview/con_poly.htm
Bottom line: Both products will clean your hair equally well, both
have the potential for drying, but the Denorex takes the additional
step of adding conditioners to help offset the drying properties of
its surfactants.
I hope this answers your question! As ever, please don't hestitate to
ask for clarification if you need additional information.
--Missy |
