LÉ Blog

Is petrolatum bad for skin?

Petrolatum is an ubiquitous skincare ingredient perhaps popularized by good ol’ Vaseline. As common and historied as it is, it’s also one that often finds itself on top of many “dirty” lists. The two main reasons you might hear about petralatum nay-sayers are “it’s a carcinogen” and “it’ll clog your pores!”. These are some pretty serious accusations! But, as cosmetic chemists who have worked with petrolatum in formulas for years, we can say that these claims are not nearly as scary as they so...

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How much niacinamide is too much niacinamide

As a skincare enthusiast, you’ve probably already heard of the irritation potential of heavy-hitting active ingredients such as retinol and glycolic acid. Niacinamide, on the other hand, gets touted as a highly efficacious yet vanilla, and gentle ingredient. But! When it comes to any ingredients, dose makes the poison… and the elixir. Most active ingredients have a tested effective range. Within that range, the ingredient should deliver those long-term benefits they promise without causing in...

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What is combination skin?

All of us have had to watch a commercial in which a smiling model applies a single product to their already-perfect skin? But you know this. We know this. Skincare commercials can definitely be fake news! There’s no magic cure-all formula that will be perfect for every inch of every single person’s face. More importantly, our skin is a dynamic creature, both person-to-person and zone-to-zone. In fact, most of us will experience skin change and experience different skin types in our lifetime. ...

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Should You Be Using PHA Gluconolactone Instead of Glycolic Acid?

There’s a (relatively) new chemical exfoliant in town – PHA (poly hydroxy acid) gluconolactone! It’s no secret that we love our AHAs (alpha hydroxy acid). These chemical exfoliants are tried and true ingredients, and we’re big proponents of them being used as staples in anyone’s routine to tackle anything from dry skin to wrinkles. That said, the gold standard AHA glycolic acid is not really made for everyone. For many people, glycolic acid may simply be too aggressive, leading to irritation,...

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RESULTS SUMMARY FOR OUR 2024 30-FOR-30 SUNSCREEN CHALLENGE

In celebration of summer, we decided to test 30 different sunscreens over 30 days to see how these applied, how they held up over time, and even how they wash off. Please head to our TikTok and Instagram channel if you want to see the visuals. Otherwise here’s the running list of sunscreens we’ve tried, our rating, and why: *To help readers learn more about products showcased in this challenge, we built out and organized these results in Shop My Shelf. We do receive a small commission for usi...

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The Chemists' Oily Skin Routine Guide

When you’re dealing with oily skin, it can end up feeling like a constant battle. Managing the shiny T-zone, worrying about breakouts, and feeling frustrated trying out new products is so common and can be a lot to deal with. However, understanding the biology behind oily skin and implementing a science-based, tailored skincare routine can help manage all your oily skin woes. So let’s delve into the root cause of oily skin, the essentials of your daily and weekly skincare routine goals, and w...

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Madecassoside - the real hero in Centella Asiatica "Cica" Skincare

Centella asiatica (a.k.a. All things “cica” in skinare) is a popular skincare ingredient that touts soothing benefits. You might be wondering what sets centella apart when it seems like every plant extract you hear about in skincare touts “soothing”, “anti-inflammatory (a big no-no since this is a drug claim but it’s out there)”, and “antioxidant” benefits. But hear it from the chemists! – very few of these ingredients actually have clinical evidence proving that they work in skincare. From t...

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Results Summary for our 2023 30-for-30 Sunscreen Challenge

In celebration of summer, we decided to test 30 different sunscreens over 30 days to see how these applied, how they held up over time, and even how they wash off. Please head to our TikTok and Instagram channel if you want to see the visuals. Otherwise here’s the running list of sunscreens we’ve tried, our rating, and why: *To help readers learn more about products showcased in this challenge, we built out and organized these results in Shop My Shelf. We do receive a small commission for usi...

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Which Vitamin C Derivative is the Best For My Skin?

We have talked about the science behind vitamin C skincare, we have even tested a bunch of CE Ferulic dupes - yet there’s still more for us to cover in the vitamin C serum landscape. Vitamin C is actually a whole family of related molecules that all behave slightly differently. The OG vitamin C with the glitzy skin benefits that you often hear of is L-ascorbic acid. But since ascorbic acid is notoriously unstable in the presence of light, water, and air, many have turned to derivative compoun...

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Your Cleansing Questions Answered: Any Scientific Takeaways Here?

In this blog post: How helpful are acne cleansers? Is there such thing as over-washing? Cleanser Formulation for Dry Skin Cleanser Impact on Rosacea Why Personal Cleanser Preference is Valid Chemists' Skin Type & Cleanser Preferences Takeaways References It would be nice if there was some scientific formula that could tell us what cleanser would best suit our skin. Most of us have spent a fair part of our adult (and young adult) lives jumping from one brand to another, hoping to find the magi...

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Mandelic Acid - Should You Choose It Over Salicylic Acid or Glycolic Acid?

AHAs (alpha hydroxy acids) such as glycolic and lactic acid have long enjoyed the spotlight - and for good reason! These are your proven chemical exfoliants essential to most anti-aging, hyperpigmentation skin routines. Beyond these two, there are plenty of “new age” AHAs that get touted for similar skin benefits, and one of the newer kids on the block we want to shine a spotlight on is mandelic acid. As chemists, we always have to look at the available clinical evidence on these newer ingred...

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