We put Sunday Riley’s Good Genes Lactic Acid Treatment to the test after receiving a complimentary sample from the brand. Keep reading for our full product review.
Lactic acid is one of the most popular alpha-hydroxy acids used in skincare—and with good reason. Much gentler than many other AHAs, this radiance-boosting acid is derived from soured milk and is known for its surface exfoliating properties, clearing away dead skin cells while diminishing the appearance of lines and discoloration. Being a lactic acid newbie myself, I tested one of the most-loved products out there, not to mention a Byrdie HQ fave: Sunday Riley’s Good Genes All-In-One Lactic Acid Treatment.
I applied it daily over the course of two weeks, noting any change in my skin’s texture, radiance, and moisture levels, as well as improvement to my dark spots and fine lines. Has this exfoliating, plumping serum treatment earned its status as a cult-favorite? Read on to find out.
Sunday Riley Good Genes All-In-One Lactic Acid Treatment
Star Rating: 4.7 / 5
Best for: Normal, dry, combination, and oily skin
Uses: Clarifying, smoothing, and retexturizing the skin; diminishing the appearance of pores and dark spots
Active Ingredients: Lactic acid, licorice, lemongrass, prickly pear extract, arnica, aloe
Potential allergens: Lactic acid, Cyclomethicone, Dimethicone, phenoxyethanol
Byrdie Clean?: Yes
About the Brand: Sunday Riley creates powerful skincare products with high-tech formulas that deliver fast, visible results. The brand also stands by its Green Technology Commitment, its pledge to only produce clean, safe products and use green practices such as producing in small batches and without artificial fragrances, mineral oil, and sulfate cleansers.
About My Skin: Normal to oily with faint fine lines
My skin’s condition varies from season to season, and summer is when it tends to bounce between normal and oily and is more prone to clogged pores and blemishes—especially now that I’m wearing a mask every time I go outdoors. I also struggle with texture and find that regardless of whether my skin is dry, oily, or somewhere in between, it’s rarely smooth. I also have noticeable sun damage from years spent tanning on the beach as a teen, showing up as small, freckly dark spots all over my cheeks.
I typically shy away from acids due to a past bad reaction to stronger ingredients and therefore had never consistently used a lactic acid treatment before now. Considering the current state of my skin and the fact that I’m beginning to notice subtle lines forming around my eyes (hello, turning 30!), Good Genes seemed like the perfect choice for my first foray into a daily AHA.
Since this product can be used day or night, I decided to incorporate it into my nighttime routine. After spritzing my clean skin with Maison Jacynthe’s Rose Floral Water, I applied Good Genes all over my face and neck and let it sink in before applying my heavier nighttime moisturizer, Haoma’s Recovery Night Cream. This product is gentle enough to apply daily so I used it every night for the duration of the two-week testing period.
Ingredients: Lactic acid works with plant botanicals to refine the skin
The key ingredient in Good Genes All-In-One Lactic Acid Treatment is, of course, lactic acid, which exfoliates pore-clogging dead skin cells on the surface of the skin and reduces the look of lines, wrinkles, and dark spots to reveal fresh, radiant skin. Lactic acid is also known to kill acne-causing bacteria, increase cell turnover, and help skin retain moisture. Additionally, licorice and lemongrass work to brighten the appearance of dark spots and other skin discoloration, while prickly pear extract, arnica, and aloe soothe the skin and calm redness.
Lactic acid is the second ingredient listed, while prickly pear extract and aloe are part of the brand’s botanical extract blend (containing other extracts and water), which is listed as the first ingredient, indicating they are all present in effective concentrations. It’s worth noting that arnica, lemongrass, and licorice are listed as the 14th, 16th, and 17th ingredients respectively, however, they aren’t the very last ingredients in the formula.
The product is considered clean by Byrdie’s standards. While it does contain some PEGs, the brand’s lab assistant has confirmed with Byrdie that any PEGs used have been stripped of contaminants and impurities. It’s also vegan, cruelty-free, gluten-free, and comes in recyclable packaging.
The Feel: Light and quick to absorb
Good Genes dispenses as a white creamy serum, but it quickly melts into the skin once applied. It’s light yet hydrating and leaves the skin feeling smooth, plump, and dewy without much of a residue. Even though I chose to use it as a nighttime treatment, its instant texture-improving benefits make it a great base for makeup.
The Scent: Citrus and floral
Sunday Riley doesn’t use any artificial fragrance in its products, but the natural botanicals in Good Genes’ formulation lend this product a delightful citrusy floral aroma.
Drying & Irritation: LA is much gentler than other acids
Compared to some of the other acids on the market, lactic acid is one of the more gentle options to choose from. Because its molecule is larger than others in comparison, it doesn’t penetrate the skin as deeply, acting as more of a surface exfoliating and polishing treatment with firming effects. Plus, it won’t disrupt the pH of your skin. I didn’t experience any irritation or dryness while using this product—in fact, I experienced quite the opposite, aside from greater sensitivity to the sun.
Sensitivity: Be wary of sun exposure and other acids
Even though lactic acid is a gentler acid, it’s still an AHA, which means it may increase your sensitivity to the sun and leave you more susceptible to sunburn. While using this product and for a week afterward, it’s best to limit sun exposure and be sure to always apply (and reapply!) SPF. However, avoiding the sun as much as possible is best, as I developed a mild sunburn after spending a day at the beach, even after consistently slathering on SPF—something I don’t typically experience.
You should also avoid mixing lactic acid with other acids and exfoliants (such as other AHAs or benzoyl peroxide) as well as retinol; this can cause redness or dryness. If your skin is particularly sensitive, the brand recommends using Good Genes as a 15-minute mask rather than a leave-on treatment.
The Results: Instantly firmer, dewier skin with radiance and texture improvement over time
Immediately after applying Good Genes the first time, my skin felt firmer, softer, and more hydrated once the product had fully absorbed. While I could feel these results more than see them, I did have a more dewy, radiant glow overall. The brand promises that the product can instantly plump fine lines and wrinkles in as little as three minutes. Up close, I did notice a slight difference in the faint lines under my eyes, though not drastic enough for someone else to notice or for my phone camera to capture. Still, a definite plus! Having used this product as a night treatment, I woke up each morning with smooth, glowing skin.
By the end of my testing period, my skin was much more radiant and had a much smoother texture. I didn’t notice any significant improvement of my sun spots or fine lines in two weeks, but I love this product for its exfoliating effects and will continue to use it. If it happens to brighten my sun spots and fade lines over time, then that’s an added bonus!
The Value: You get what you pay for
Earlier this year, Sunday Riley lowered the price of Good Genes by 20%, dropping it to $85 per fluid ounce from $105. While $85 isn’t cheap—and there are certainly plenty of affordable lactic acid products on the market—Sunday Riley prides itself on using clean, high-quality ingredients and science-based, green formulations. In my opinion, you’re getting what you pay for.
Similar Products: There’s competition
The Ordinary Lactic Acid 5% + HA 2%: There are plenty of Good Genes dupes on the market available at a range of price points, but one of the most popular is The Ordinary’s Lactic Acid 5% + HA 2% serum, a liquid serum with a mild exfoliating effect. Both products contain ingredients that soothe the skin and help combat the redness and irritation associated with acids. (Good Genes uses prickly pear extract, arnica, and aloe, while The Ordinary uses a derivative from the Tasmanian pepperberry plant.) The Ordinary offers an extra hydration boost with hyaluronic acid, while Good Genes is formulated with licorice and lemongrass to help brighten the appearance of dark spots and discolorations.
While I haven’t tested The Ordinary’s serum personally, both products have rave reviews. If you’re new to acids and are hesitant to shell out on an introductory product, The Ordinary’s serum is significantly less expensive (we’re talking $6.50 for one fluid ounce), so it might be the better option for you. And if you’re looking for something a bit more powerful, The Ordinary offers a 10% lactic acid version for a mere 20 cents more.
Sunday Riley Good Genes Glycolic Acid Treatment: If you’re looking for a deeper treatment, Sunday Riley also offers a glycolic acid version of Good Genes. Glycolic acid is a stronger acid than lactic acid, penetrating the surface of the skin to unclog pores and repair sun-damaged, congested, wrinkled, or dull skin. It also contains potassium lactate, a member of the lactic acid family, so it still provides the gentle surface exfoliation and a hydration boost of the Good Genes Lactic Acid Treatment. And, like its sister product, it contains prickly pear extract to soothe and calm the complexion from the effects of using acids.
While I haven’t tried this one yet myself, it’s next on my list—especially now that I’m no longer afraid of incorporating acids into my routine.
Our Verdict: An effective radiance-boosting treatment
Overall, Sunday Riley's Good Genes All-in-One Lactic Acid Treatment was the perfect skin pick-me-up, leaving me with a visibly more radiant, soft, and plump complexion in just two weeks. It’s earned itself a permanent spot in my bedtime routine, and I’m looking forward to seeing if it has any effect on my sun spots and fine lines.