– Written by Dr. Roma Patil, Intern, BMCRI

Shampoo bottles usually mention a long list of complicated and confusing ingredients, making it difficult to decipher whether you are buying the right product with the right ingredients for your hair type. Nowadays, the topic of hair and skin care is in vogue, and all kinds of viral “routines” are making the rounds on social media. People are ready to pay hefty prices for their beauty products, which has created a huge industry selling lots of hair care products to fulfill the demand. To make things easier for you, I will dissect all the usual ingredients that go into a shampoo, so that you can make informed decisions for your crowing glory.

A shampoo is technically designed to clean the scalp of sebum and prevent the development of folliculitis and seborrheic dermatitis. Shampoos are intended to rid the hair of sebum, sweat components, skin debris, styling products, and environmental dirt. But modern shampoos are expected to be much more than mere cleansing agents. They are expected to not dry out the hair; to produce lather in hard and soft water; to be non-irritating to skin and mucous membranes; to be chemically and physically stable; to possess conditioning benefits; to be biodegradable; and affordable. Incidentally, the term shampoo entered the English language through India where the Hindi word “champoo” was used meaning to press or massage; it was used to denote cleaning through massage of the hair and skin.

The basic recipe for a shampoo is listed in Table 1.

DetergentsFunctions to remove environment dirt, styling products, sebum, and skin scales from the hair and scalp
Foaming agentsThis agent allows the shampoo to form suds, as consumers equate cleansing with foaming even though the two are unrelated
ConditionersLeave the hair soft and smooth after sebum removal by the detergent
ThickenersThicken the shampoo, as consumers feel that a thick shampoo works better than a thin shampoo
OpacifiersAdded to make a shampoo opaque as opposed to translucent for aesthetic purposes, unrelated to cleansing
Sequestering agentsFunctions to prevent soap scum from forming on the hair and scalp in the presence of hard water; The basic difference between a liquid shampoo and a bar cleanser
FragrancesAdded to give the shampoo a consumer-acceptable smell
PreservativesPrevent microbial and fungal contamination of the shampoo before and after opening
Specialty additivesTreatment ingredients or marketing aids added to impart other benefits to the shampoo, besides hair and scalp cleansing
Table 1


Shampoos usually contain synthetic detergents or surfactants as primary cleansers. A detergent or surfactant is amphiphilic, meaning the detergent molecules contains both lipophilic (oil-attracting) and hydrophilic (water-attracting) sites. The lipophilic sites help to bind sebum and oily dirt while hydrophilic end binds to water; allowing removal of the sebum while washing with water. 

There are five categories of shampoo detergents: Anionics, Cationics, Non-ionics, Amphoterics and Natural. Each of this group possesses different hair cleansing and conditioning qualities

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Anionic detergents are the most popular surfactants used in basic cleansing shampoos in the current market. Anionic detergents are exceptionally adept at removing sebum from the scalp and hair. But, hair devoid of all sebum is harsh, rough, subject to static electricity, dull, and hair that needs detangling. 

Lauryl sulfates: 

Examples: Sodium lauryl sulfate, triethanolamine lauryl sulfate, and ammonium lauryl sulfate

Most shampoos designed to produce good hair cleansing will contain lauryl sulfate as the second or third ingredient listed on the label, with water being the primary ingredient. They work well in both hard and soft water, produce rich foam, and are easily rinsed. 

Laureth sulfates 

Examples: Sodium laureth sulfate, triethanolamine laureth sulfate, and ammonium laureth sulfate.

Laureth sulfates are one of the most commonly used primary detergents in general shampoos designed for normal-to-dry hair. They provide excellent cleansing, but leave the hair in good condition. Consumers like these detergents, as they produce abundant foam. 


Examples: Lauryl sarcosine and sodium lauryl sarcosinate.

Sarcosines are generally not used as primary detergents, as they do not remove sebum well from the hair. However, they are excellent conditioners and commonly used as the second or third listed detergent on the shampoo ingredient list. Sarcosines are used in conditioning shampoos and dry hair shampoos. 


Examples: Disodium oleamine sulfosuccinate and sodium dioctyl sulfosuccinate.

Sulfosuccinates are a class of strong detergents useful in removing sebum from oily hair. For this reason, they are a common secondary surfactant in oily hair shampoos. 


Examples: Long-chain amino esters, ammonioesters, cetyltrimethylammonium chloride.

They are poor cleansers and do not lather well and are not compatible with anionic detergents, limiting their utility. However, they are excellent at imparting softness and manageability to chemically damaged hair and so are primarily used as daily shampoo for damaged hair such as in case of permanently dyed or chemically bleached hair. 


Examples: Polyoxyethylene fatty alcohols, polyoxyethylene sorbitol esters and alkanolamides.

The nonionic detergents are the second most popular surfactants, behind the anionic detergents. These are the mildest of all surfactants and are used in combination with ionic surfactants as a secondary cleanser.


Examples: Cocamidopropyl betaine and sodium lauraminopropionate.

Having both positively and negatively charged polar group, they behave differently at lower pH (as cationic detergent) and at higher pH (as anionic detergent). Subgroups include the betaines, sultaines, and imidazolinium derivatives. They are used in baby shampoo and for those with fine and damaged hair because they don’t cause stinging in the eyes in children, foam well and leave hair in manageable state. 


Examples: Sarsaparilla, soapwort, soap bark, and ivy agave

These natural saponins have excellent lathering capabilities, but are poor cleansers thus must be present at high concentration. Usually, they are combined with other synthetic detergents that provide most of the hair and scalp cleansing, while the botanicals are largely added for marketing purposes.


Example: Cocodiethanolamide

They introduce gas bubbles into the water but have nothing to do with cleansing, a common myth among general population that a product which foams better cleans better. Inclusion of foam boosters help to satisfy this customer psyche, though it does help spread the detergent over the hair and scalp. Sebum inhibits the bubble formulation; therefore, there is more foam during second shampooing.



Opacifier: Glycol distearate

Thickener: Sodium chloride, PEG-150 distearate

These ingredients are used to change the physical and optical properties of the shampoo. Thickeners increase the product viscosity, which many consumers feel makes a better shampoo. Opacifiers are used to make shampoos have a pearly shine, which offers no improved cleansing, only an optical effect.


Example: Polyphosphates and ethylenediaminetetra-acetic acid

Sequestering agent used to chelate magnesium and calcium ions. Presence of these ions form insoluble soaps called “scum” over the scalp and hair, may cause itching and exacerbate the symptoms of seborrheic dermatitis while making the hair dull


To address the treatment of the scalp; shampoos must not have a pH higher than 5.5, which is also scalp pH. Hair shaft swelling which occurs due to alkalization of hair shaft after use of most detergents can be prevented by “pH balancing” the shampoo by the addition of an acidic substance, such as glycolic acid or citric acid to adjust the pH down to approximately 5.5. Use of “neutral pH” shampoo helps for chemically treated hair, from either permanent dyeing or permanent waving.


Example: Sodium benzoate, parabens, 1,3-dimethylol-5,5-dimethyl (DMDM) hydantoin, tetrasodium EDTA, methylisothiazolinone, or MIT and Quaternium-15.

Preservatives resist germs and prevent decomposition of the shampoos. They also prevent various other health risks that accompany contamination by germs and bacteria. 


Example: Hydrolyzed animal protein, glycerin, dimethicone, simethicone, polyvinylpyrrolidone, propylene glycol, and stearalkonium chloride 

The conditioner functions to impart manageability, gloss, and antistatic properties to the hair. Protein-derived substances are popular conditioners for damaged hair, as they can temporarily mend split ends, also medically known as trichoptilosis.


  • Sulfates: They increase skin sensitivity and strip hair of their natural oils, causing dryness
  • Parabens: They increase the risk of skin cancer
  • Sodium Chloride: It can make an already-sensitive scalp dry and itchy, which can eventually cause hair loss.
  • Synthetic Fragrances: Products that have “fragrance” on their label can contain thousands of hidden chemicals. Some ingredients in fragranced cosmetic products can disrupt the reproductive system and cause cancer or asthma. They can also irritate the skin and scalp, which can lead to hair loss.
  • Synthetic Colors: Most shampoos and conditioners are dyed with a synthetic color to make them look nice. These colors come from petroleum or coal-tar sources, all of which come with harmful health effects. Synthetic colors will normally go by FD&C or D&C combined with a number.
  • Phthalates:They are dangerous to the environment and cause hormonal disruptions
  • Formaldehyde: Is carcinogenic and easily absorbed by the skin
  • Dimethicone: It prevents moisture from entering the hair and clogs pores over time
  • Retinyl palmitate: Causes itching, scaling, and peeling
  • Alcohol: Makes your hair dry and brittle
  • Toluene: Can hamper the immune system and cause congenital problems
  • Cocamidopropyl Betaine: Although it’s derived from coconut oil, it can have negative effects. This surfactant is used in hair products along with dimethylaminopropylamine, which can cause skin irritation, allergies, rosacea, and eczema.
  • Triclosan: Triclosan was banned from being used in antibacterial soaps in 2016 but is still allowed in toothpaste, shampoos, and deodorants. It’s a chemical antibacterial agent known to cause hormone disruptions, which can lead to cancer and affect fetal development, among other things.


  1. Trüeb, R. M. (2007). Shampoos: Ingredients, efficacy and adverse effects. JDDG, 5(5), 356–365. doi:10.1111/j.1610-0387.2007.06304.x 
  2. Draelos ZD. Essentials of Hair Care often Neglected: Hair Cleansing. Int J Trichology. 2010;2(1):24-29. doi:10.4103/0974-7753.66909
  3. D’Souza P, Rathi SK. Shampoo and Conditioners: What a Dermatologist Should Know?. Indian J Dermatol. 2015;60(3):248-254. doi:10.4103/0019-5154.156355

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