CGM-Approved vs. Banned Ingredients: The Full List

What Are CGM-Approved and Banned Ingredients?

The Curly Girl Method (CGM) is a hair care framework developed by stylist Lorraine Massey, first published in her 2001 book Curly Girl: The Handbook. Its core premise is that conventional shampoo formulations — especially sulfate-based ones — strip curly and wavy hair of the natural oils it needs, while silicone-based conditioners create buildup that only those same harsh shampoos can remove. Breaking this cycle, Massey argued, allows hair's natural curl pattern to emerge.

Understanding why certain ingredients are banned or approved requires understanding the science of hair structure and the chemistry of what these ingredients actually do.

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Hair Structure: Why Curly Hair Is Different

Hair is a three-layered biomaterial: an outer cuticle of overlapping scales, a cortex containing the bulk of the fiber's keratin proteins, and a medulla at the center. The cuticle surface is coated with 18-methyleicosanoic acid (18-MEA), a lipid layer that makes hair naturally hydrophobic and gives it slip and shine.

Curly and coily hair has an elliptical cross-section rather than a round one, which causes the cuticle to lie less flat and creates natural points of weakness along each bend. Sebum — the scalp's natural oil — travels down a straight shaft easily but distributes slowly along a curly one, leaving the lengths and ends naturally drier. This structural reality is why curly hair is disproportionately affected by harsh cleansing and why the CGM argument has scientific grounding.

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Banned Ingredients

Sulfates

Sulfates are anionic surfactants — negatively charged detergent molecules that create lather and remove oil and dirt. The most common in shampoos are:

• Sodium lauryl sulfate (SLS)
• Sodium laureth sulfate (SLES)
• Ammonium lauryl sulfate (ALS)
• Ammonium laureth sulfate (ALES)
• Sodium myreth sulfate

SLS is the more aggressive of the two primary sulfates. Research published in Colloids and Surfaces B found that immersing hair in a sulfate solution caused twice as much protein loss as immersing it in water alone — a direct measure of structural damage. Anionic surfactants also deposit negative charges on the hair fiber surface. Because hair is already negatively charged (particularly when damaged), this charge repulsion raises the cuticle, increases surface roughness, and amplifies frizz. A 2015 review in the International Journal of Trichology confirmed that anionic surfactants can increase frizz and friction.

SLES is meaningfully milder than SLS because an additional ethoxylation step reduces its irritation potential — the European Scientific Committee on Consumer Safety (SCCS) distinguishes the two on safety grounds. For people with straight, oily hair who wash frequently, SLES is generally well tolerated. For curly, dry, or chemically treated hair where sebum distribution is already uneven, even SLES can over-strip.

How to spot sulfates on a label: Look for ingredients ending in -sulfate: sodium lauryl sulfate, sodium laureth sulfate, ammonium lauryl sulfate. They appear in the first five ingredients of most conventional shampoos.

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Water-Insoluble Silicones

Silicones form a thin film over the hair cuticle that reduces friction, blocks humidity, adds shine, and detangles. The problem the CGM identifies is specific: water-insoluble silicones cannot be rinsed off with water or mild surfactants. They require sulfate-based cleansers to remove — which reintroduces exactly what the method eliminates. The result is cumulative buildup that weighs hair down, dulls curl definition, and blocks moisture absorption.

A 2025 peer-reviewed review in Skin Appendage Disorders (Karger) confirmed that "prolonged use of water-insoluble silicones, such as dimethicone, can lead to accumulation on the hair shaft" and that their removal requires potent cleansing agents that may themselves cause dryness.

Banned (water-insoluble) silicones include:

Gray area — water-soluble silicones: Some CGM practitioners accept water-soluble silicones because they rinse cleanly without sulfates. The key water-soluble variant is:

• Dimethicone copolyol (also called PEG-modified dimethicone)

Whether to include water-soluble silicones is a practitioner decision; strict CGM excludes all silicones; modified CGM accepts soluble variants.

How to spot silicones on a label: Most end in -cone, -conol, -xane, or -siloxane: dimethicone, cyclomethicone, dimethiconol, cyclopentasiloxane, amodimethicone.

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Drying Short-Chain Alcohols

Alcohols divide sharply into two groups in hair care. The CGM bans short-chain, volatile alcohols that evaporate quickly and draw moisture from the hair shaft with them:

• Ethanol / Ethyl alcohol / SD alcohol / Alcohol denat.
• Isopropyl alcohol / Isopropanol
• Propanol
• Propyl alcohol

These appear in hairsprays, some gels, and many conventional styling products to speed drying and improve spreadability. They dehydrate the hair fiber. The higher they appear in an ingredient list, the greater the concentration and concern.

Do not confuse these with fatty alcohols (see Approved section below), which share the word "alcohol" but are chemically and functionally opposite.

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Waxes and Mineral Oils

Mineral oil, petrolatum (petroleum jelly), and waxes are large, occlusive molecules that coat the hair shaft. They provide shine and manageability in the short term but create buildup that mild cleansers cannot shift. Like insoluble silicones, they trap the CGM practitioner in a dependence on sulfate shampoos to clarify.

Commonly banned in CGM:

• Mineral oil (paraffinum liquidum)
• Petrolatum / petroleum jelly / Vaseline
• Beeswax (cera alba)
• Carnauba wax
• Microcrystalline wax
• Lanolin (debated — some practitioners accept it as a natural oil)

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Approved Ingredients

Sulfate-Free Cleansers

CGM-approved cleansers use milder surfactant classes that lift dirt and sebum without the aggressive stripping of SLS. These include:

A 2018 article in Skin Appendage Disorders characterized co-washing — using a conditioner with cetyl alcohol as its primary cleanser — as "good for dry, sensitive, overprocessed, and textured hair," while noting it cannot remove silicones, mineral oil, or petrolatum, which is exactly why those are banned.

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Fatty Alcohols (Emollients)

Despite the word "alcohol," fatty alcohols are long-chain molecules derived from plant fats (commonly coconut and palm) that are CGM's primary conditioner base. They are emollients and emulsifiers, not drying solvents. The FDA permits products labeled "alcohol-free" to contain cetearyl alcohol — recognition that it is categorically distinct from ethanol.

CGM-approved fatty alcohols:

• Cetyl alcohol (C16)
• Cetearyl alcohol (C16/C18 blend)
• Stearyl alcohol (C18)
• Behenyl alcohol (C22)

Studies show no irritation or sensitization with cetyl alcohol at concentrations up to 8.4% in formulations. The International Journal of Trichology (2015) classified these as nonionic surfactants with "excellent dermatological properties." They appear in nearly every CGM-approved conditioner.

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Humectants

Humectants attract water molecules and hold them in the hair shaft, improving softness and definition. CGM approves them, but with an important climate caveat.

Common CGM-approved humectants:

• Glycerin (glycerol) — the most widely used; highly effective in moderate humidity
• Propylene glycol — similar to glycerin; smaller molecule
• Sorbitol — sugar-derived humectant
• Honey — natural sugar-based humectant
• Aloe vera — contains multiple humectant sugars plus polysaccharides
• Hyaluronic acid — film-forming; holds water more broadly
• Panthenol (pro-vitamin B5) — penetrates the cortex; improves elasticity

The dew point complication: Humectants draw moisture from whichever source is most abundant — the atmosphere if humidity is high, or the hair shaft itself if the air is dry. In low dew-point conditions (cold winters, heated indoor air, arid climates), glycerin and similar humectants can pull moisture out of the hair. During these periods, CGM practitioners reduce or eliminate glycerin-heavy products, or pair them with heavier sealants (oils, shea butter) to offset the moisture draw. In moderate and high dew-point conditions, glycerin excels.

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Cationic Conditioning Polymers

Cationic (positively charged) polymers are attracted to the negative surface charge of hair and deposit conditioning agents along the fiber. They are the backbone of most rinse-out and leave-in conditioners. The Polymers (Basel) 2023 review confirmed that cationic conditioners work by "neutralization of the electrical negative charge of the hair fiber," reducing friction and improving manageability.

CGM-approved cationic ingredients:

• Behentrimonium chloride (BTAC) — gentle, detangling; the standard in natural/CGM conditioners
• Behentrimonium methosulfate (BTMS) — a fatty quaternary used as an emulsifier; very mild
• Polyquaternium-10, -11, -28 — film-forming; widely used; low buildup risk at typical concentrations
• Guar hydroxypropyltrimonium chloride — plant-derived from guar bean; conditioning + slip
• Hydrolyzed proteins (hydrolyzed keratin, silk, rice, wheat, quinoa protein) — penetrate the cortex at low molecular weight; temporarily reinforce the hair shaft

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Plant Oils and Butters

Light and medium-weight plant oils are CGM-approved sealants and emollients. They do not build up in the same way as mineral oil or silicones because they are metabolized or absorbed differently and can be removed by mild surfactants.

CGM-approved oils (most to least penetrating):

• Coconut oil — the deepest-penetrating hair oil; reduces protein loss (confirmed in Journal of Cosmetic Science, 2003)
• Argan oil — light; high oleic acid content; adds shine
• Jojoba oil — wax ester; closely resembles sebum; non-greasy
• Avocado oil — rich in oleic acid; penetrates cortex
• Sweet almond oil — lighter emollient; good for fine hair
• Castor oil — heavy; best used sparingly on ends only (buildup risk with excess)
• Shea butter — rich butter; best for coarse/high-porosity hair; sealant

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Hold and Defining Ingredients

Curly hair gels and creams use film-forming polymers to cast the curl and reduce frizz. CGM-approved hold agents are water-soluble and wash out cleanly.

CGM-approved hold ingredients:

• Flaxseed (linseed) extract — natural gel with polysaccharides; strong hold; fully CGM-approved
• Aloe vera gel — light hold + humectancy
• Polyquaternium-4, -10, -11 — conditioning hold polymers
• Carbomer — gel-forming polymer (water-soluble; rinses cleanly)
• Hydroxyethylcellulose (HEC) — plant cellulose derivative; light hold; water-soluble

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Quick-Reference Tables

Banned Ingredients Cheat Sheet

Approved Ingredients Cheat Sheet

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Reading an Ingredient List: Practical Rules

1. Scan the first five ingredients first. Ingredients are listed in descending order of concentration. If SLS or dimethicone appears in the top five, it dominates the formula.
2. Look for -sulfate (sodium lauryl sulfate, ammonium lauryl sulfate) — this catches most banned cleansers.
3. Look for -cone, -conol, -xane, -siloxane — this catches most banned silicones.
4. Distinguish alcohols. Ethanol, isopropyl alcohol = banned. Cetyl alcohol, cetearyl alcohol = approved. The chemical name "SD alcohol" is always a drying alcohol.
5. Waxes are listed as "wax," "cera," or "microcrystalline." Mineral oil appears as "paraffinum liquidum" in INCI nomenclature.
6. Free tools such as isitcg.com allow ingredient list scanning and will flag non-CGM-approved components automatically.

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The Nuance: What the Evidence Actually Supports

The CGM's core logic — that harsh cleansers combined with non-removable silicones trap curly hair in a damage-frizz cycle — is directionally supported by peer-reviewed hair science. The Skin Appendage Disorders (2018) review confirmed that sulfates "have been associated with an increase in frizz, hair fragility, and scalp dryness" and that co-washing is "good for dry, sensitive, overprocessed, and textured hair."

However, the same review also noted that "there are no scientific data to prove" co-washing alone prevents breakage or regulates sebum production, and that it "cannot provide a good level of cleanliness for the hair and scalp" — requiring clarifying every 15 days with a stronger cleanser to remove excess sebum and residue.

The scientific consensus supports:

• Sulfate-free cleansing for dry/curly/chemically treated hair — well evidenced
• Avoiding water-insoluble silicone buildup — mechanistically sound
• Using fatty alcohols and mild cationic conditioners — strongly supported
• Avoiding all silicones categorically — overstated; water-soluble silicones do not build up and can provide genuine conditioning benefits

The method is best understood as a framework that works very well for many people with dry, textured, or chemically treated hair — not a rigid rulebook whose every prohibition is equally supported by evidence.

For related guidance on how to build a CGM routine, see CGM for wavy hair and the foundational Curly Girl Method guide. If scalp oiliness is a concern, CGM for oily scalp addresses the cleansing compromise. For the co-washing vs. low-poo decision specifically, see low-poo vs. co-wash.