Reviva Labs Skin Texturizing Day Creme with ALA -- 2 oz

Since a young age, you’ve been taught to avoid acids. The word itself is harsh and slightly irritating. Like most rules, though, there is an exception. In this case, it’s the acids in skin care. For decades, skincare products have been formulated with acids that are not only safe but remarkably effective. Skincare acids have been known to eradicate blemishes, fade dark spots, smooth fine lines and so much more. Different acids have different benefits, though. And it can be hard to keep them all straight, let alone know which ones are best for your skin type. This guide is here to clear the air – and, hopefully, help clear you of any pesky skin woes.

The Main Types of Acids in Skincare

Almost all acids in skin care can be categorized into three main buckets: alpha-hydroxy acids, (AHAs), beta-hydroxy acids (BHAs) and poly-hydroxy acids (PHAs). All three types of skincare acids work as chemical exfoliants, weakening the bonds between dead skin cells. However, there are some key differences between them. The most significant disparity is their chemical structure, as this affects how the acids interact with your skin.

Alpha-hydroxy acids

Alpha-hydroxy acids are chemical compounds that occur naturally in sugar cane, fruits and milk. These unique acids are made up of water-soluble molecules, which means a couple things. For one, their affinity for water helps improve skin’s moisture content. (Good news for dry or sun-damaged skin!) The other important note: they exfoliate by breaking down surface-level skin cells (and you know why you should exfoliate). While higher concentrations of AHAs result in a more intense exfoliation, the molecules rarely go deeper than the outer most layers of skin. This is why AHAs are primarily used for mild hyperpigmentation, surface wrinkles and dull, uneven skin tone.

Beta-hydroxy acids

Beta-hydroxy acids are typically derived from willow bark and sweet birch trees. Willow bark contains salicin, which is a compound used to create salicylic acid. You’ve probably seen salicylic acid in various acne-fighting products. This popular BHA works, because these acids are made of oil-soluble molecules. They penetrate much deeper than AHAs to effectively break up the dirt and excess oil that clogs pores. BHAs are beloved for their antibacterial and anti-inflammatory effects, as well.

Polyhydroxy acids

Frequently referred to as the “second generation of AHAs,” polyhydroxy acids have quickly picked up steam in the industry. These acids are made up of large water-soluble molecules, which prevents them from penetrating skin. They don’t even go as deep as AHAs. But that’s a good thing. PHAs offer a gentler exfoliation, making them suitable for ultra-sensitive skin types or those who simply can’t tolerate other exfoliants. PHAs have also been shown to have antioxidant powers.

The other guys

There are some common skincare ingredients that don’t fall under any of the hydroxy acid families. These include antioxidants, like vitamins A, C and E. These nutrients fight free radical damage, which can be brought on by stress, pollution, radiation, cigarette smoke and other toxic chemicals you may be exposed to on a regular basis. There are other acids not specifically categorized as an AHA, BHA or PHA. Think hyaluronic acid, azelaic acid and ferulic acid, to name a few. Keep an eye out for these “other guys” in your skincare products. The most notable mentions are discussed in the guide below.

A Comprehensive Guide: What the Acids in Skin Care Can do for You

Everything to this point was a broad overview of the different types of skincare acids. Now it’s time for the nitty-gritty details. Below is a list – from A to Z – of the most commonly used acids in skin care and their unique benefits. Find the ones that are right for you!

Azelaic acid

What’s it known for?

• Fighting acne
• Diminishing discoloration

Azelaic acid belongs to a group called dicarboxylic acids, which is related to carboxylic acids like AHAs and PHAs. The difference is that this particular acid offers antibacterial properties, specifically against p. acnes. It also inhibits discoloration by penetrating skin and slowing down the production of melanin. The best part is azelaic acid plays well with others. You may find it mixed with BHAs, retinoids, niacinamide or hyaluronic acid. If it’s singled out, expect high concentrations of azelaic acid – like 10%, 15% or even 20%. Who should use it and how? Anyone fighting blemishes caused by p. acnes would benefit from azelaic acid. It even helps with acne scars. On that same note, moms who developed mild melasma after having kids are good candidates for azelaic acid. When applied topically, it can help lighten and brighten different forms of hyperpigmentation. Where do I find it? For decades, azelaic acid was only available by prescription and was used to treat severe skin disorders. Now, it’s more widely available over the counter, but in lower concentrations. It’s mostly formulated into all-over skin creams that are, typically, designed to fight acne.

Ascorbic acid (L-ascorbic acid/vitamin C)

What’s it known for?

• Antioxidant protection, particularly against UV radiation

This is another notable mention. L-ascorbic acid is the most commonly used, synthetic form of vitamin C. Between its highly researched antioxidant benefits and key role in collagen production, vitamin C is a must-have for healthy skin. Some studies have shown that topical application of ascorbic acid “may help prevent and treat ultraviolet-induced photodamage.” One hiccup, however, is that this water-soluble nutrient is very unstable. Exposure to air, heat or light can quickly compromise the integrity of your vitamin C skin care. Who should use it and how? Since ascorbic acid is so effective at protecting against UV radiation, it’s a no-brainer for people who spend lots of time in the sun. Another factor with excessive sun exposure is dry skin and wrinkles. Using ascorbic acid may help stimulate collagen production, which keeps skin looking firm and supple. Where do I find it? A standalone vitamin C serum is the popular choice and probably your best bet. In a serum, you’ll find higher concentrations of L-ascorbic acid. You want a concentration of at least 10% due to vitamin C’s vulnerability to degradation.

Citric acid (AHA)

What’s it known for?

• Antioxidant protection
• Improving texture and appearance

Not surprisingly, citric acid is an AHA derived from citrus fruits. Hence its potent antioxidant properties. Like other AHAs, citric acid exfoliates the top layers of skin and encourages cell turnover. This is essential for maintaining a smooth texture and appearance. In addition to its healthy skin benefits, citric acid is sometimes used in cosmetics to adjust or stabilize the product’s pH. Who should use it and how? This is one of the milder, less acidic AHAs, so don’t be afraid to use it on sensitive skin. Where do I find it? According to the U.S. Food and Drug Administration’s Voluntary Cosmetic Registration Program, citric acid was used in almost every category of cosmetic products. It’s not hard to find.

Ellagic acid

What’s it known for?

• Brightening skin
• Smoothing wrinkles
• Antioxidant protection, particular against UV-B exposure

Ellagic acid is another outlier. Chemically speaking, it’s a polyphenol found in fruits and vegetables, such as raspberries, strawberries, cranberries and pomegranates. Polyphenols offer potent antioxidant benefits. Specifically, ellagic is known for protecting skin against UV-B irradiation and the wrinkles that tend to form after prolonged exposure. These effects were seen in a 2010 study conducted on mice, which demonstrated that ellagic acid prevented collagen degradation and inflammation caused by UV-B rays. Who should use it and how? This polyphenol is best suited for those concerned with wrinkles or other photoaging effects, such as pigmentation, dryness or rough skin. Ellagic acid is safe for all skin types. Where do I find it? Its antioxidant benefits make ellagic acid the perfect complement to sun care products, as well as moisturizers and face serums.

Ferulic acid

What’s it known for?

• Brightening skin
• Smoothing fine lines and wrinkles
• Antioxidant protection
• Stabilizing other antioxidants

Ferulic acid is another antioxidant found naturally in fruit seeds, vegetables and nuts. Like all other antioxidants, it fights the damaging effects of free radicals. As you know, free radicals can break down skin’s collagen, cause hyperpigmentation and irritate skin in a number of other ways. Who should use it and how? Anyone spending time under the sun should consider ferulic acid. Apply it under your moisturizer and SPF. Where do I find it? Ferulic acid is most often used in nourishing face serums. It may be combined with retinol, niacinamide or other, less stable antioxidants. In fact, research says that incorporating ferulic acid with vitamins C and E stabilizes these nutrients and significantly enhances sun protection. Photoprotection actually doubled from four-fold to eight-fold with this trio of antioxidants in one formula.

Galactose (PHA)

What’s it known for?

• Promoting collagen production
• Contributing to wound healing

There’s limited research and knowledge surrounding galactose. But here’s what’s available so far: galactose is a naturally occurring sugar that skin uses to synthesize collagen. In vitro research also indicates “galactose may play a role in wound healing.” Who should use it and how? Galactose is considered a mild acid, most suitable for mature and sensitive skin types, particularly those needing to smooth skin tone and texture. Where do I find it? Despite the growing popularity of PHAs, galactose is not yet well-adopted by skincare companies. If and when it does get picked up, expect to find galactose in serums and face masks.

Gluconolactone (PHA)

What’s it known for?

• Exfoliating dead skin cells
• Brightening skin
• Hydrating the outer layers of skin

Also known as gluconic acid, this PHA is a derivative of glucose – you know, the naturally occurring nutrient needed to power all cells in the human body. When topically applied, gluconolactone effectively accelerates cell turnover. Specifically, it helps dissolve dark, dead skin cells and produce a brighter, more even complexion. Its large molecules are also effective at pulling moisture from the air in order to soothe dry skin. These molecules, then, form a barrier on skin’s outermost layer to seal in the water. Who should use it and how? Gluconolactone is best suited for those with hyperpigmentation, with mature skin or those who are sensitive to AHAs. Like all PHAs, this one is well-tolerated by people with rosacea or eczema and can be used on a daily basis. Where do I find it? This PHA is commonly used in creams and serums. Note: gluconolactone may serve as an active ingredient or simply an additive that improves the overall quality and stability of the formula.

Glycolic acid (AHA)

What’s it known for?

• Exfoliating dead skin cells
• Evening skin tone
• Minimizing pores
• Fighting acne

Derived from sugar cane, glycolic acid is one of the smallest molecules in the AHA family. Being small and water-soluble helps it penetrate skin more deeply than the average AHA. This is why glycolic acid is so effective at sloughing off dead skin cells, promoting cell turnover and stopping acne at the comedone (blackhead) stage. Who should use it and how? A highly concentrated glycolic acid cream is a great alternative to retinol for women who are pregnant, nursing or who simply can’t tolerate retinol. If you have sensitive skin, it’s best to start with a low concentration of glycolic acid and low frequency. Once skin becomes conditioned, you can bump up either the concentration or number of times you use the product each week. Where do I find it? Many skin peels, creams and toners incorporate glycolic acid to boost their exfoliating efforts. At-home solutions will have a maximum concentration of 10%. But you can find stronger formulations at your dermatologist’s office, where they might use it with microdermabrasion or micro-needling treatments.

Hyaluronic acid

What’s it known for?

• Hydration, hydration, hydration!
• Effectively plumping skin for a more youthful appearance

Hyaluronic acid (HA) is a humectant derived from sugar. Hyaluronic acid’s magic trick is that it can hold up to 1,000 times its weight in water, which is exceptionally beneficial for skin health. It not only draws in moisture, but is able to retain it for a smoother, fresher appearance. Who should use it and how? Like collagen and elastin, natural production of HA decreases with age. The sooner you start incorporating it into your skincare regime, the better. Once you do, it won’t take much to keep skin hydrated. HA’s ability to hold water means skin stays nourished all day long. Where do I find it? If you use a moisturizer of any kind, chances are you’re already using hyaluronic acid. It’s a common addition to creams and serums, though it can also be found in facial cleansers that promise to hydrate. When shopping, look for a micronized or multi-molecular hyaluronic acid. HA is a large molecule that cannot penetrate deep into skin on its own. It must be modified or paired with a vehicle to reach below the epidermis.

Kojic acid

What’s it known for?

• Brightening skin

Interestingly enough, kojic acid is a byproduct in the fermentation of rice used for making sake. It’s produced by several fungi, most commonly Aspergillus oryzae, whose common name in Japanese is koji. It’s used in food as a natural preservative. In cosmetics, kojic acid is regarded as a skin-lightening agent, much like hydroquinone. Unlike hydroquinone, however, kojic acid has not been found to have negative effects on skin health. Who should use it? Small doses of kojic acid can help those with acne scars, sun-induced hyperpigmentation or age spots. It’s a potent acid, which means a little goes a long way. Sensitive skin types should beware of kojic acid’s strong effects. Where do I find it? Kojic acid is primarily used in brightening serums and sometimes cleansers. The concentration is very low due to limitations set by consumer safety groups.

Lactic acid (AHA)

What’s it known for?

• Exfoliating dead skin cells
• Hydrating

Lactic acid is another popular AHA. It’s made up of large, water-soluble molecules that are limited to the outer layers of skin. As its name implies, lactic acid is commonly derived from lactose found in milk, though it can also come from fruit sugars. Because of its molecular structure, lactic acid is able to effectively remove dead skin cells while also providing moisture to those outer layers. Who should use it and how? Fortunately, lactic acid is suitable for all skin types, especially those looking for a more radiant complexion. Depending on the concentration of lactic acid in your skin care, it’s generally safe for everyday use. It is, however, temperamental to pH. Try to use lactic acid products with a pH of 3.5 to 4. And while it can be combined with nourishing ingredients, like hyaluronic acid, avoid layering lactic acid with benzoyl peroxide, retinol or even other AHAs. Where do I find it? Lactic acid is commonly found in peels and exfoliating serums. Over-the-counter skin care treatments can go up to 12% lactic acid concentration, but you probably won’t need anything above 10%.

Lactobionic acid (PHA)

What’s it known for?

• Hydrating skin cells
• Firming and thickening skin
• Antioxidant protection

Lactobionic is the second most common PHA, next to gluconolactone. It comes from oxidized milk sugar – usually that found in cow’s milk. Lactobionic acid is a strong humectant and antioxidant. Working as an antioxidant chelating substance, lactobionic acid was shown to suppress “matrix metalloproteinase enzymatic activity.” In layman’s terms, it protects against further sun damage and significantly increases skin firmness and thickness. Who should use it and how? If your skin could use a good moisture boost, lactobionic acid is a great addition to your skin care routine. It’s a true PHA, gentle and nourishing. That said, lactobionic acid should not be mixed with other hydroxy acids. And avoid using any exfoliating treatments – peels, pads, brushes – with lactobionic acid. It’s best applied to clean, bare skin. Where do I find it? There’s a growing number of scrubs, serums, peels and masks formulated with lactobionic acid. Typically, it’s an acid you’ll find in the skincare products you use at night.

Malic acid (AHA)

What’s it known for?

• Exfoliating dead skin cells
• Brightening skin
• Fighting acne

Malic acid is an AHA that tends to fly under the radar, primarily because it doesn’t have too much power on its own. It’s often combined with other AHAs, BHAs and hydrating ingredients like hyaluronic acid. Like other AHAs, malic acid is naturally found in fruits and vegetables. It gently exfoliates skin’s outermost layer, which promotes a brighter complexion and clearer pores. Who should use it and how? It’s safe to use malic acid products up to twice daily to achieve glowing skin. It’s a good choice for the acne-prone and sensitive skin types, which may be irritated by other acids. Where do I find it? Daily face peels and overnight creams are often formulated with a combination of malic acid, glycolic acid and/or lactic acid. Derma e Essentials Overnight Peel, for example, is teeming with 5% AHAs and a pH of 3 for the most effective exfoliation.

Mandelic acid (AHA)

What’s it known for?

• Improving texture
• Hydrating skin cells
• Soothing irritated skin
• Reducing hyperpigmentation

Mandelic acid is another lesser-known AHA made up of large molecules. It’s derived from bitter almonds, but has a sweet, gentle approach to exfoliation. As a result, mandelic acid promotes skin cell turnover, which leads to a smoother, more even texture. A 2013 study evaluated mandelic acid for its anti-aging benefits. Researchers discovered it can, in fact, help perimenopausal women with dryness and irritation. Other studies have proven it effective for treating melasma due to its anti-inflammatory effect, as well as improving skin firmness by almost 24%. Mandelic acid also has antioxidant properties. Who should use it and how? Mandelic acid is so gentle it can be used on all skin types, including sensitive skin. Apply a mandelic acid product at night after washing your face. Gently pat the solution into skin and give it a few minutes to settle before adding a moisturizer over top. Where do I find it? Mandelic acid is often formulated with other AHAs to enhance exfoliation. Look for it in at-home facial peels and cleansers.

Phytic acid (AHA)

What’s it known for?

• Antioxidant protection
• Brightening skin

If you’ve read about the nutritional benefits of beans, you may have learned about phytic acid. It’s the substance in beans that causes flatulence (yeah, not cool). In the skincare industry, though, phytic acid is an esteemed ingredient. It’s touted for its antioxidant functions (super cool!). Though technically considered an AHA, phytic acid does not specifically exfoliate skin. Instead, it reduces free radical damage and brightens skin. Who should use it and how? Most skin types are receptive to phytic acid. That said, those with UV damage or acne-prone skin benefit the most. If your skin is sensitive, stick to pure phytic acid formulas. The mixing of acids is more likely to irritate skin. Where do I find it? Most likely, phytic acid is already in some of the skincare products you know and love. It’s often formulated with other AHAs and BHAs, which is why you’ll find it in everything from peels and moisturizers to pore purifiers and blemish treatments. Salicylic acid (BHA) What’s it known for?

• Fighting acne

Salicylic acid is a BHA that occurs naturally in willow bark. This particular BHA is both keratolytic and comedolytic, meaning it can shed dead skin cells and resolve comedones (aka blackheads). Salicylic acid gets deep into pores to dissolve dirt and oil that leads to breakouts. It also has mild antibacterial and anti-inflammatory properties. Don’t expect salicylic acid to be your only acne attacker, though. It has not been shown to kill p. acnes, the bacteria most commonly associated with acne. You’ll get better results pairing salicylic acid with a stronger antibacterial, such as benzoyl peroxide. Who should use it and how? If you have acne-prone skin, chances are you’ve used a product with salicylic acid. Despite its mild antibacterial effects, regular use of salicylic acid is great at clearing blemishes. In fact, its mild nature is what makes it safe for all skin types and skin tones. Where do I find it? Because salicylic acid is so well-studied and well-understood, there’s no shortage of it in skincare products. It can be found in everything from skin-clearing foundation to acne-fighting body wash. On the product label, it might be identified as willow bark extract. You may also find properties of salicylic acid in other forms. Salicylate, for instance, is a salt or ester of salicylic acid. Note: the FDA points out that, chemically speaking, salicylic acid is not a true BHA. “However, cosmetic companies often refer to it as a BHA and, consequently, many consumers think of it as one.”

Tartaric acid (AHA)

What’s it known for?

• Exfoliating dead skin cells
• Improving texture
• Stabilizing skin pH
• Antioxidant protection

You may not have heard of tartaric acid, but it works just as well as more popular AHAs. It comes from fruits, most notably grapes, bananas and citrus. Tartaric acid has many of the same properties as glycolic acid and lactic acid, meaning it effectively sloughs off dead skin cells to improve texture and reduce signs of aging. Who should use it and how? Tartaric acid is considered safe and a low risk for all skin types. In fact, it has shown fewer signs of irritation than other AHAs. Where do I find it? Tartaric acid is commonly found in formulations with glycolic acid and/or lactic acid. It enhances their effectiveness. Most of these products are chemical peels or resurfacing solutions, which promise a brighter, more even skin tone.

5 Tips for Using Different Acids in Your Skincare Routine

1. Consult a dermatologist. While this is a comprehensive skin care acids guide, it doesn’t have all the answers. For more clarity on the exact products you should be using, consult a certified dermatologist. They will perform a thorough assessment in order to lay out the most effective routine for your skin type. 2. Always patch test. Anytime you use a new skincare product, take the time to test it out. Apply a pea-sized amount on the back of your hand or earlobe. Wait a few minutes and observe any reactions – good or bad. Be mindful that higher concentrations are more likely to irritate skin. You may need to gradually build a tolerance for these formulations. Start by using the product twice a week. If your skin doesn’t become irritated with that cadence, bump it up to three or four times per week. 3. Don’t mix and match. Most of the hydroxy acids don’t mesh well together. You may occasionally see AHAs and BHAs formulated together in one product. These usually provide lower concentrations and are meant to be used sparingly (not daily!). The worst thing you can do is layer one potent AHA on top of a single BHA. The combined power of these chemical exfoliators easily irritates skin. A smarter strategy: use different hydroxy acids on alternating days. Or, use one in the morning and another at night. 4. Use (sun) protection. Acids in skin care are designed to strip the top layer of skin, which makes you more sensitive to UV exposure. If you apply any chemical exfoliant during your morning beauty routine, make sure it goes below a broad-spectrum sunscreen. Your sunscreen should protect against UVB and UVA rays with at least SPF 15. Only using vitamin C or hyaluronic acid? This applies to you, too. Harmful UV exposure can enhance cellular oxidation, thereby reducing the effectiveness of your skincare solutions. 5. Re-evaluate if you become pregnant. Canadian researchers concluded most problem-solving skincare products are safe to use during pregnancy, with the exception of hydroquinone and retinoids. That said, human studies of topically applied skincare acids are limited. Your healthcare provider will likely recommend avoiding BHAs, particularly salicylic acid. Be sure to discuss your skincare routine in detail, so your healthcare provider can guide you in the right direction.