Lab Notes

Skincare ingredients that target redness

Redness in skincare is a common issue caused by factors like UV exposure, barrier damage, over-exfoliation, and genetics. While removing the root cause can help, redness-prone skin often requires a multi-faceted approach. Key players in redness include Toll-like Receptor-2 (TLR-2), which triggers inflammation, and serine proteases, enzymes that overreact in sensitive skin, causing irritation. Other contributors like Protease-Activated Receptor-2 (PAR-2) and inflammatory cytokines also amplify redness. By using ingredients that target these pathways, you can reduce inflammation and calm redness for healthier, balanced skin.

Redness is a common skincare issue, especially for beginners who are still figuring out the right products and routines. It can result from a variety of factors, including UV exposure, damage to the skin barrier, over-exfoliation, physical irritation, allergic reactions, stress, heat, and even genetics. With so many possible causes, redness is often the result of trial and error, making it tricky to address.

The first and most effective way to reduce redness is by identifying and eliminating the root cause. However, for people with skin that is naturally prone to redness, this may not be enough. Reducing or controlling redness often requires a multi-faceted approach because it involves a variety of skin processes working together.

In this guide, we’ll break down the key biological mechanisms involved in redness and inflammation in the skin and list ingredients that target each of these pathways.

Toll-like Receptor-2 (TLR-2) “Skin’s Airport Customs Officer”

Toll-like receptors (TLRs) are a critical part of your skin’s defense system. Think of TLR-2 as the "airport customs officer" of your skin—it inspects everything that tries to pass through, distinguishing between friendly substances (naturally occurring elements in your skin) and harmful invaders (like bacteria, mites, and UV damage).

When TLR-2 detects a potential threat, it triggers an inflammatory response to fight off the danger. While this is a helpful defense mechanism, in people with conditions like rosacea, TLR-2 can become overactive, causing the skin to react to even minor irritants. It's like having an overly strict customs officer who flags even the smallest issue. This can lead to excessive redness and inflammation.

Luckily, certain skincare ingredients can help calm down an overactive TLR-2, reducing unnecessary inflammation.

  • Phospholipids like Phosphatidylglycerol
  • Ellagitannins from Alchemilla vulgaris
  • Alpha Arbutin
  • Some Flavonoids like Xanthohumol from Hops
  • Salicylates from Willow bark
  • Curcumin and Tetrahydrocurcumin from Turmeric
  • Emodin from Rhubarb root
  • Polyphenols like Resveratrol
  • Niacinamide
  • Retinoids

Serine Proteases “Skin’s Airport Police”

Serine proteases are enzymes that regulate many important skin functions, including exfoliation (the shedding of dead skin cells), maintaining the skin’s barrier, controlling inflammation, and managing pigmentation. They play a crucial role in keeping your skin balanced and healthy.

Think of serine proteases as the "airport police." When TLR-2 (the customs officer) detects something wrong, it calls for backup, and serine proteases respond to handle the situation. However, in conditions like rosacea or eczema, the serine proteases overreact and call in too much help, leading to an exaggerated inflammatory response—like sending in a SWAT team for a minor security breach.

This overreaction causes redness, irritation, and inflammation. Fortunately, certain topical ingredients can reduce serine protease activity and prevent them from calling in the unnecessary backup.

  • Azelaic acid
  • Niacinamide
  • Tranexamic acid

Protease Activated Receptor-2 (PAR-2) “911 Operator”

Protease-Activated Receptors (PARs) are communication hubs between different types of skin cells. PAR-2, in particular, acts like the "911 operator" of your skin. It facilitates communication between keratinocytes (the main type of skin cell) and other cells such as melanocytes (pigment-producing cells) and immune cells.

When skin damage occurs, serine proteases can "call" PAR-2 for help. The problem is, like an overzealous 911 operator, PAR-2 sometimes sends an excessive response—leading to symptoms like hyperpigmentation, barrier damage, itching, and, most significantly, increased inflammation.

By using ingredients that target PAR-2, we can reduce this exaggerated response and prevent unnecessary inflammation and redness.

  • Niacinamide
  • Nordihydroguaiaretic acid (NDGA)
  • Paeonol from Peony root
  • Punicalagin from Pomegranate

Inflammatory Cytokines 

Cytokines are small proteins that act as messengers in the immune system. They’re responsible for coordinating the body's response to injury or infection. In the context of skin inflammation, certain cytokines, such as IL-1, IL-8, IL-17, and TNF-a, play key roles in driving redness and inflammation.

These cytokines signal immune cells to leave the bloodstream and go to the site of injury, which results in increased blood flow and redness. While this is a normal immune response, in people with rosacea or other inflammatory skin conditions, these cytokines are often overactive, leading to chronic redness.

Many plant-based ingredients and botanicals have been studied for their ability to inhibit these inflammatory cytokines, making them popular choices in redness-reducing skincare formulations.

  • Bisabolol
  • Quercetin
  • Kaempferol
  • Baicalein
  • Rutin
  • Ginsenoside
  • Avenanthramides
  • Withanolides
  • Ursolic acid
  • Naringenin
  • Apigenin
  • Gingerol
  • Paradol
  • Glycyrrhetinic acid
  • Boswellic acid
  • Allantoin
  • Paeoniflorin
  • Paeonol
  • Madecassoside
  • Asiaticoside
  • A heck ton of botanicals like Boerhavia diffusa, Epilobium angustifolium

Peroxisome Proliferator-Activated Receptor (PPAR)

PPARs are nuclear hormone receptors, which means they work inside the nucleus of cells to regulate gene expression. They play a key role in maintaining the skin’s barrier, reducing inflammation, and controlling pigmentation.

If you think of retinoids (vitamin A-based products) as targeting skin cell turnover and rejuvenation, PPARs are more focused on maintaining balance in the skin’s barrier and keeping inflammation under control. Targeting PPARs can help soothe inflammation and redness, especially for people with skin conditions like rosacea.

  • Linoleic acid
  • Azelaic acid
  • Pterostilbene
  • Palmitoylethanolamide
  • Hydroxystearic acid
  • Ximenynic acid
  • Oleanolic acid
  • Ursolic acid

Vascular Endothelial Growth Factor (VEGF)

VEGF is a growth factor that promotes the growth of new blood vessels. This process is essential for healing, but in some cases—especially in people with rosacea or sun-damaged skin—VEGF can be overactive, leading to the development of visible, tiny blood vessels (telangiectasia) on the skin’s surface.

Once these blood vessels form, they cannot be removed by topical treatments; laser therapy is typically required. However, we can use skincare ingredients to inhibit VEGF activity and prevent these blood vessels from forming in the first place.

UV exposure, genetics, and overuse of topical steroids can all trigger VEGF, making it important to use protective and calming ingredients to keep VEGF under control and prevent persistent redness.

  • Naringenin
  • Naringin
  • Oleuropein
  • Ursolic acid
  • Ellagic acid
  • Mangostin
  • Mangiferin
  • Baicalin
  • Scutellarein
  • Rosmarinic acid
  • Ginsenoside
  • Artemisinin
  • Stigmasterol
  • Sulforaphane
  • Apigenin
  • Nobiletin
  • Myricetin
  • Hydroxytyrosol

By understanding how these different skin processes contribute to redness and inflammation, you can choose topical treatments that specifically target the root causes. Although managing redness can be complex, combining products that address each of these mechanisms can make a significant difference in calming your skin and keeping it healthy.

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