Unveiling Lash Serums: What They Do, How They Work, and Potential Side Effects

Written by: Brilliant Staff

Fact checked by: Heather Snead, Licensed Esthetician

Unveiling Lash Serums: What They Do, How They Work, and Potential Side Effects

We all dream about owning a pair of glamorous lashes to elevate our beauty game. As a result the beauty industry introduced us to lash serums — a cosmetic shortcut to longer, fuller-looking, lashes. But are lash growth serums all they’re cracked up to be? In this article, we delve into the mechanics of lash serums, how they work,  and their potential side effects. 

What Are Lash Serums? 

A lash serum is a unique cosmetic formula intended to enhance the appearance of eyelashes. In addition to offering lengthier, denser, more voluminous lashes, many lash serums also are also designed to enrich, condition, and safeguard lashes from potential damage or breakage. Most lash serums are formulated with ingredients like peptides, vitamins, and nourishing extracts, which moisturize to help stimulate the production of keratin — a protein essential for hair, skin, and nails.

Why Do We Lose Volume in Our Lashes? 

Like any type of visible hair thinning, there are multiple factors behind why we lose volume in our lashes. 

1. Aging

Aging is one of the main drivers behind diminishing lash health. As you grow older, the hair all over your body — including your lashes — tends to thin due to decreased efficiency at the follicle level. 

2. Moisture Balance

Eyelashes, like other hair strands, require a certain level of moisture to remain healthy. When the skin in the eye area becomes excessively dry, it can cause lashes to become dry and brittle, making them prone to thinning and breakage.

3. Cosmetics and Improper Care

Excessive use of harsh makeup or negligent removal can lead to eyelash breakage. Furthermore, mechanical stress — like curling your lashes or using false ones — can lead to a visible reduction in hair volume and lash damage.

4. Allergies

Lash volume loss can also occur due to allergic reactions to specific eye-care products or even contact lens solutions.

The Science Behind Lash Serums

Over the years, lash serums have made significant improvements in formula efficacy.A higher percentage of subjects treated with bimatoprost 0.03% (78.1%) versus vehicle (18.4%) demonstrated at least a 1-grade increase in global eyelash assessment score at week 16 (P < .0001). Subjects in the bimatoprost 0.03% group also had statistically significantly greater increases in eyelash length, thickness, and darkness.

Since bimatoprost is a prescription drug, most over-the-counter lash serums don’t use it in their formulas, however, that doesn’t necessarily rule out their role in achieving longer-looking lashes. In one clinical trial, subjects who used poly-growth factor serum for 90 days observed improvements in length (10.52%), volume (9.3%), luster (11.43%), thickness (35%), and curl (50.83%).

Ingredients to Look for in an Over-The-Counter Lash Serum

When considering an over-the-counter lash serum, certain nourishing ingredients may hold the key to promoting healthier, more robust-looking lashes. Here are some ingredients to check for:

1. Biotin

Part of the B-vitamin family, biotin is widely recognized for its positive effects on hair health and is often used to help strengthen lashes and prevent breakage and thinning.

2. Panthenol

Also known as Provitamin B5, Panthenol helps condition and increase lash flexibility and durability. This ingredient is also used to add luster and volume to lashes.

3. Castor Oil

Rich in ricinoleic acid, a monounsaturated fatty acid, castor oil is a plant-derived ingredient that deeply penetrates to help nurture lashes. 

4. Aloe Vera

Used widely in skincare for its gentle, soothing properties, aloe vera's moisturizing benefits may also extend to nurturing lashes.

5. Bamboo and Green Tea Extracts

Bamboo and green tea extracts can offer a wealth of antioxidants and nutrients when applied topically. Green tea is an excellent way to achieve longer, darker lashes. A fabulous source of a polyphenol called epigallocatechin; this component can help in the growth of new lashes besides giving a boost to the old ones.

While these ingredients can bring lash-enhancing properties to your serum, it's still important to remember that what works for one person may not work for another. Always do a patch test when trying a new serum to check for any adverse reactions.

The Flip Side: Skepticism and Potential Side Effects

Despite strong anecdotal evidence and some promising preliminary research, there is not yet a scientific consensus on the efficacy of lash serums as continued research is needed.

Not all lash serums are manufactured equally; the purity and efficacy of formulations can vary significantly from product to product. It is imperative to conduct proper research and choose a product from a reputable brand that is upfront about the ingredients and realistic about the  results it claims to produce.

The Final Verdict

Many people have experienced success with lash serums, citing  noticeable improvements in length, thickness, and volume. But just like any other health or beauty product, they also harbor potential risks.

Is lash serum a miraculous solution for luxuriant lashes? According to mainstream science, serums may be a promising solution to improved lash health, however, it’s still too early to form a final consensus. If you’re considering using a serum to elevate your lash game, as always, do your research and consult a healthcare professional before buying. 


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