Isshi The Hair Milk Dx Deep Repair Moist Leave-In Treatment Versus Hair Theory Lab Milk Serum
Updated on April 24, 2025
Overview
What they are
These products are both reef safe . They have a total of 21 ingredients in common
Cool Features
They both contain ceramides and hyaluronic acid
Suited For
They're both likely to be good for anti aging, dry skin, brightening skin, sensitive skin and scar healing
Free From
They both do not contain any parabens
What's Inside
They both contain harsh alcohols, fragrances and silicones
We independently verify ingredients, and our claims are backed by peer-reviewed research. Spot a product that needs an update? Let us know.
Ingredient Info
Isshi The Hair Milk Dx Deep Repair Moist Leave-In Treatment 64 ingredients
Hair Theory Lab Milk Serum 40 ingredients
About this product
About this product
At a glance
Click on any of the items below to learn more
Isshi The Hair Milk Dx Deep Repair Moist Leave-In Treatment 64 ingredients
Hair Theory Lab Milk Serum 40 ingredients
Key Ingredients
Benefits
Concerns
Benefits
Concerns
Ingredients Side-by-side
Ingredients Explained
These ingredients are found in both products.
Ingredients higher up in an ingredient list are typically present in a larger amount.
Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.
So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.
You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Stay hydrated!
Learn more about WaterDimethicone is a type of synthetic silicone created from natural materials such as quartz.
What it does:
Dimethicone comes in different viscosities:
Depending on the viscosity, dimethicone has different properties.
Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.
This ingredient is unlikely to cause irritation because it does not get absorbed into skin. However, people with silicone allergies should be careful about using this ingredient.
Note: Dimethicone may contribute to pilling. This is because it is not oil or water soluble, so pilling may occur when layered with products. When mixed with heavy oils in a formula, the outcome is also quite greasy.
Learn more about DimethiconeDipropylene Glycol is a synthetically created stabilizer and solvent. It is a part of the glycol class in the alcohol family.
Dipropylene Glycol helps dissolve and evenly distribute ingredients. It also helps decrease viscosity and thin out texture.
As a masking agent, Dipropylene Glycol can be used to cover the smell of other ingredients. However, it does not have a scent.
Studies show Dipropylene Glycol is considered safe to use in skincare.
Learn more about Dipropylene GlycolAminopropyl Dimethicone is a type of silicone.
Heptanol is a fragrance.
Sodium Lauroyl Glutamate is the sodium salt from the lauric acid of glutamic acid.
It is a surfactant and helps cleanse the skin. Surfactants gather oil, dirt, and other pollutants from your skin so they may be washed away easily.
Dimethiconol is a silicone that resembles the popular dimethicone. Like other silicones, it is an emollient. Emollients create a thin film on skin to prevent moisture from escaping.
This ingredient helps to create a silky texture and improve spreadability. Due to its high molecular weight and thickness, it is often combined with cyclopentasiloxane.
This water-soluble silicone is used for its hydrating and softening properties. It is used to add a silky feel to skincare products and has great benefits for haircare.
In haircare, this ingredient:
- Adds shine
- Protects color
- Offers thermal protection
- Boosts hair strength
- Does not build up as easily
We don't have a description for Gamma-Docosalactone yet.
Sodium Hyaluronate is hyaluronic acid's salt form. It is commonly derived from the sodium salt of hyaluronic acid.
Like hyaluronic acid, it is great at holding water and acts as a humectant. This makes it a great skin hydrating ingredient.
Sodium Hyaluronate is naturally occurring in our bodies and is mostly found in eye fluid and joints.
These are some other common types of Hyaluronic Acid:
Learn more about Sodium HyaluronateHydrolyzed collagen has a misleading name because it is actually a mixture of various proteins/peptides. This ingredient has skin hydrating properties.
Collagen is the most abundant type of structural protein found in your body. In your skin, it is responsible for keeping it firm and youthful.
Hydrolyzed Collagen is created by breaking up proteins into smaller peptide bonds. These peptides act as humectants and emollients.
Humectants are great at holding onto water, keeping skin hydrated. Emollients create a thin barrier on the skin to prevent moisture from escaping.
There is ongoing debate about whether hydrolyzed collagen works because it increases skin hydration. Skin hydration is also linked to elasticity and the appearance of wrinkles.
Collagen or peptide ingredients can be used in the morning or night. They will not increase sun sensitivity, but you should always wear sunscreen during the day.
According to a manufacturer, this ingredient is a great hair conditioner as well.
This ingredient can be extracted from different sources, including:
Vegan collagen is derived from yeast, bacteria, or plant sources. Vegan collagen would go by a different INCI name, such as hydrolyzed soy protein.
The results are varied.
A study from 2021 found hydrolyzed collagen increased elasticity and improved wrinkles in 1,125 participants between age 20 and 70. Another study found increased skin thickness in participants between the ages of 45 to 59.
However, It is difficult to prove that oral collagen will end up working on your skin. Many of the studies using hydrolyzed collagen also add several vitamins and nutrients into the test mixture as well.
Further studies are needed at this time.
Learn more about Hydrolyzed CollagenCeramide NG is a type of Ceramide. The NG stands for a sphinganine base.
Ceramides are intercellular lipids naturally found in our skin that bonds dead skin cells together to create a barrier. They are known for their ability to hold water and thus are a great ingredient for dry skin.
Ceramides are an important building block for our skin barrier. A stronger barrier helps the skin look more firm and hydrated. By bolstering the skin ceramides act as a barrier against irritating ingredients. This can help with inflammation as well.
If you would like to eat ceramides, sweet potatoes contain a small amount.
Read more about other common types of ceramides here: Ceramide AP Ceramide EOP Ceramide NP
Learn more about Ceramide NgSteartrimonium Chloride is a preservative.
We don't have a description for Dicocodimonium Chloride yet.
We don't have a description for Ceteth-20 yet.
Cetearyl alcohol is a mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is mainly used as an emulsifier. Emulsifiers help prevent the separation of oils and products. Due to its composition, it can also be used to thicken a product or help create foam.
Cetearyl alcohol is an emollient. Emollients help soothe and hydrate the skin by trapping moisture.
Studies show Cetearyl alcohol is non-toxic and non-irritating. The FDA allows products labeled "alcohol-free" to have fatty alcohols.
This ingredient is usually derived from plant oils such as palm, vegetable, or coconut oils. There is debate on whether this ingredient will cause acne.
Due to the fatty acid base, this ingredient may not be Malassezia folliculitis safe.
Learn more about Cetearyl AlcoholButylene Glycol (or BG) is used within cosmetic products for a few different reasons:
- It is a solvent, meaning that it helps to dissolve other ingredients. This also enhances the absorption of the product into one's skin.
- It is a humectant, which means that it helps attract moisture into the skin.
- It helps improve product application.
- It has mild preservative properties.
Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
Pentylene glycol is typically used within a product to thicken it. It also adds a smooth, soft, and moisturizing feel to the product. It is naturally found in plants such as sugar beets.
The hydrophilic trait of Pentylene Glycol makes it a humectant. As a humectant, Pentylene Glycol helps draw moisture from the air to your skin. This can help keep your skin hydrated.
This property also makes Pentylene Glycol a great texture enhancer. It can also help thicken or stabilize a product.
Pentylene Glycol also acts as a mild preservative and helps to keep a product microbe-free.
Some people may experience mild eye and skin irritation from Pentylene Glycol. We always recommend speaking with a professional about using this ingredient in your routine.
Pentylene Glycol has a low molecular weight and is part of the 1,2-glycol family.
Learn more about Pentylene GlycolDisodium EDTA plays a role in making products more stable by aiding other preservatives.
It is a chelating agent, meaning it neutralizes metal ions that may be found in a product.
Disodium EDTA is a salt of edetic acid and is found to be safe in cosmetic ingredients.
Learn more about Disodium EDTAPhenoxyethanol is a preservative that has germicide, antimicrobial, and aromatic properties. Studies show that phenoxyethanol can prevent microbial growth. By itself, it has a scent that is similar to that of a rose.
It's often used in formulations along with Caprylyl Glycol to preserve the shelf life of products.
Parfum is a catch-all term for an ingredient or more that is used to give a scent to products.
Also called "fragrance", this ingredient can be a blend of hundreds of chemicals or plant oils. This means every product with "fragrance" or "parfum" in the ingredients list is a different mixture.
For instance, Habanolide is a proprietary trade name for a specific aroma chemical. When used as a fragrance ingredient in cosmetics, most aroma chemicals fall under the broad labeling category of “FRAGRANCE” or “PARFUM” according to EU and US regulations.
The term 'parfum' or 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term.
For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance by INCI standards.
One example is Calendula flower extract. Calendula is an essential oil that still imparts a scent or 'fragrance'.
Depending on the blend, the ingredients in the mixture can cause allergies and sensitivities on the skin. Some ingredients that are known EU allergens include linalool and citronellol.
Parfum can also be used to mask or cover an unpleasant scent.
The bottom line is: not all fragrances/parfum/ingredients are created equally. If you are worried about fragrances, we recommend taking a closer look at an ingredient. And of course, we always recommend speaking with a professional.
Learn more about ParfumIngredient Ratings
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