What's inside
What's inside
Key Ingredients
Benefits
Concerns
Ingredients Side-by-side
Reviews
Ingredients Explained
These ingredients are found in both products.
Ingredients higher up in an ingredient list are typically present in a larger amount.
Methylparaben is a synthetic preservative and one of the most widely used in the world. It has a simple, but important job: prevent your products from going bad by stopping bacteria, yeast, and mold from growing.
Typical use levels are low, often 0.1-0.3%.
This is also one of the most heavily studied preservatives out there and major regulatory bodies have repeatedly given it the green light.
In 2023, the EU's Scientific Committee on Consumer Safety (SCCS) confirmed that this ingredient is safe up to 0.4% on its own, of up to 0.8% when mixed with other paraben esters.
Here's the science behind the noise behind parabens/hormones as well:
Methylparaben shows very weak estrogen-like activity in vitro tests (more than 1,000x weaker than your body's own estradiol). In vivo (live-organism) studies don't support a meaningful endocrine-disrupting effect either.
It's also a low sensitizer and allergic reactions are uncommon; they usually happen on damage or broken skin.
There is a caveat: France has proposed to formally re-examine its endocrine classification in 2025 so the regulatory conversation isn't fully closed as of yet.
But as it stands today, this ingredient is considered safe at permitted levels.
Learn more about MethylparabenPropylene Glycol is a synthetic, colorless, odorless liquid that has been a staple in cosmetics for decades. It is a skin conditioning agent, humectant, and solvent.
As a humectant, it draw water to the skin to reduce flaking and restore suppleness. It's also a solvent that helps dissolve other actives and keeps formulas stable across temperature changes.
The CIR Expert Panel has confirmed this ingredient to be nontoxic and clinical studies show no sensitization at cosmetic use concentrations.
True allergic reactions are quite rare: a 15-year retrospective study of 6,751 patients found only 0.31% had a positive reaction (and less than half were considered clinically relevant).
It seemed that when sensitization does occur, it's most commonly linked to topical medication (like corticosteroids) and not cosmetics. Allergic contact dermatitis also appears largely limited to individuals with underlying skin conditions.
Overall, propylene glycol is a well-studied ingredient that most people can tolerate without issue.
Learn more about Propylene GlycolTretinoin is the best retinoid due to its proven skin benefits. It only available with a prescription in many countries.
All retinoids goes through a conversion line until it can become effective. The final step of conversion is retinoic acid; retinoic acid IS Tretinoin.
This is why tretinoin is so effective; it gets to work immediately on the skin.
Research on tretinoin has found it to be incredibly effective for reducing the signs of aging. It helps improve damage from the sun, even the skin tone, and smooth out wrinkles. It is also an effective acne treatment by reducing and balancing out sebum production in pores.
Tretinoin, like other forms of Vitamin A, increases the turnover cycle of skin cells. This helps the skin create newer and healthier skin cells faster.
It can cause irritation, redness, and dry skin because it is considered a "strong" ingredient. Those with sensitive skin should consult a professional about using tretinoin.
Using retinoids will increase sun-sensitivity in the first few weeks of use. Though studies show retinoids increase your skin's natural SPF with continuous use, it is best to always wear sunscreen and sun-protection.
Read about a form of retinoid you can purchase at the store, retinol.
Learn more about Tretinoin
