Ingredient review
Isostearic/Myristic Glycerides
INCI: ISOSTEARIC/MYRISTIC GLYCERIDES
A gentle, semi-synthetic emollient that softens and smooths skin without clogging pores, ideal for sensitive and dry skin types.
In plain English
Isostearic/Myristic Glycerides are a blend of fatty compounds derived from plant oils (like coconut or palm) and then modified to be more stable and spreadable. In skincare, they act like a skin-softening agent that fills in the tiny gaps between skin cells, making your skin feel smoother and look more hydrated. Think of them as a lightweight, non-greasy oil that helps your moisturizer glide on easily and keeps your skin barrier healthy.
Review score
Safety, usefulness, and evidence
Potentially useful with some tradeoffs
The evidence base is useful, but some claims depend heavily on the formula.
Risk flags are low for most users, though the finished product can still irritate.
- Source
- semi synthetic
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Useful, but context matters
Isostearic/Myristic Glycerides is generally a lower-concern ingredient when the full formula suits your skin.
Plain-English read
Treat this as a practical screening step before you compare products that contain this ingredient.
- Step 1Start with the score, then check the irritation and clogging risk before judging Isostearic/Myristic Glycerides.
- Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
- Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.
Score terms in plain English
Irritation risk
lowLess likely to sting, burn, or bother most users, though sensitive skin can still react.
Clogging risk
lowLess likely to feel heavy or contribute to clogged pores for most skin types.
Evidence level
moderateThere is useful support, but formula details and claim strength still matter.
What it is
A mixture of glycerides (glycerol bound to fatty acids) from isostearic and myristic acids, typically produced from vegetable oils through esterification. It is a semi-synthetic ingredient, meaning it starts from natural sources but is chemically processed to improve performance.
How it works
It forms a thin, breathable film on the skin's surface that reduces water loss (transepidermal water loss, or TEWL) and helps other ingredients penetrate better. Its molecular structure mimics the skin's natural lipids, so it integrates into the skin barrier to improve softness and flexibility.
Pros
Gentle on sensitive skin
With a low irritation risk, it's unlikely to cause redness or stinging, making it a safe choice for those with eczema or rosacea.
Non-comedogenic
It has a low comedogenic rating, meaning it won't clog pores or contribute to acne breakouts, even for oily skin types.
Cons and cautions
Sustainability concerns
If sourced from palm oil, it may contribute to deforestation unless certified sustainable. Look for RSPO-certified products.
Limited research
Compared to more common emollients like glycerin, there are fewer peer-reviewed studies specifically on this ingredient blend.
Best for
- People with dry or dehydrated skin needing gentle moisture
- Those with sensitive or reactive skin looking for a low-irritation emollient
Use caution if
- Individuals with a known allergy to fatty acid derivatives (rare)
Usage tips
Safety summary
Isostearic/Myristic Glycerides are considered safe for topical use in cosmetics. They have low irritation and comedogenic potential, and no significant toxicity has been reported in standard safety assessments. However, as with any ingredient, patch testing is recommended for those with extremely sensitive skin.
Research notes
Research on this specific blend is limited, but the individual fatty acids (isostearic and myristic) are well-studied and recognized as safe emollients. The Cosmetic Ingredient Review (CIR) panel has evaluated similar glycerides and found them safe for use in cosmetics.
Common label clues
- Typical concentration
- 1% to 10%
- Regulatory status
- Approved for use in cosmetics by the FDA and EU CosIng database as a skin-conditioning agent with no known restrictions.
- Common uses
- Moisturizers, Creams, Lotions, Lip products, Hair conditioners
- Environmental note
- May be derived from palm oil; choose products with RSPO certification or plant-based alternatives to support sustainable sourcing.
Good to know
- It is often used as a replacement for mineral oil in 'natural' formulations.
- The ingredient is stable and has a long shelf life in products.
Common questions
What is Isostearic/Myristic Glycerides in beauty products?
Isostearic/Myristic Glycerides are a blend of fatty compounds derived from plant oils (like coconut or palm) and then modified to be more stable and spreadable. In skincare, they act like a skin-softening agent that fills in the tiny gaps between skin cells, making your skin feel smoother and look more hydrated. Think of them as a lightweight, non-greasy oil that helps your moisturizer glide on easily and keeps your skin barrier healthy.
What does Isostearic/Myristic Glycerides do in a beauty product?
It forms a thin, breathable film on the skin's surface that reduces water loss (transepidermal water loss, or TEWL) and helps other ingredients penetrate better. Its molecular structure mimics the skin's natural lipids, so it integrates into the skin barrier to improve softness and flexibility.
Is Isostearic/Myristic Glycerides safe for most people?
Isostearic/Myristic Glycerides are considered safe for topical use in cosmetics. They have low irritation and comedogenic potential, and no significant toxicity has been reported in standard safety assessments. However, as with any ingredient, patch testing is recommended for those with extremely sensitive skin.
Who should be careful with Isostearic/Myristic Glycerides?
Individuals with a known allergy to fatty acid derivatives (rare)
Research sources
Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.