Truology C-Boost Intense Defense Serum
The hero of the range — 20% Tetrahexyldecyl Ascorbate at a concentration built for sensitive skin without sacrificing potency.
Sensitivity, dryness, and visible redness often rule out standard vitamin C serums. C-Boost addresses this with a lipid-soluble, highly stable form of vitamin C that integrates into the skin's lipid matrix rather than sitting on the surface, supported by a 15-antioxidant defense system for broad-spectrum protection against free radicals, UV-induced lipid peroxidation, blue light, and pollution.
Truology products are cosmetic skincare formulations. Results vary between individuals depending on skin type, routine, and lifestyle. Product information is provided for general informational purposes and is not intended to diagnose, treat, cure, or prevent any disease or condition.
- 20% Tetrahexyldecyl Ascorbate — a lipid-soluble, highly stable vitamin C that penetrates deeply and stimulates collagen synthesis.
- 15-Antioxidant Defense System — astaxanthin, ferulic acid, glutathione, ergothioneine, and green tea polyphenols.
- Bisabolol, Licorice Root & Turmeric Extract — calm visible redness and support barrier resilience.
- Squalane & Sodium Hyaluronate — maintain optimal hydration and skin suppleness.
- Improves overall skin health, brightness, dryness, and redness
- Broad-spectrum protection against free radicals, UV, blue light, and pollution
- Gentle enough for sensitive skin and under-eye use
- Non-tacky, non-irritating, fragrance-free
33 women, 6 weeks, used with Barrier Restore twice daily and A² Retinal Serum nightly: 85.71% improved overall skin health · 78.57% improved brightness · 75.00% improved dryness · 67.86% improved background redness.
Use every morning and evening after cleansing. Apply to dry face, neck, and décolletage.
Water, Tetrahexyldecyl Ascorbate, Squalane, Glycerin, Propanediol, Caprylic/Capric Triglyceride, Cetearyl Alcohol, Sodium Hyaluronate, Tripeptide-2, Astaxanthin, Bisabolol, Glutathione, Ergothioneine, Cetearyl Olivate, Sorbitan Olivate, Ceteareth-20, Ferulic Acid, Fulvic Acid, Plankton Extract, Chlorella Vulgaris Extract, Zingiber Officinale (Ginger) Root Extract, Camellia Sinensis (Green Tea) Leaf Extract, Vitis Vinifera (Grape) Seed Extract, Curcuma Longa (Turmeric) Root Extract, Glycyrrhiza Glabra (Licorice) Root Extract, Arctostaphylos Uva-Ursi-Leaf (Bearberry) Extract, Tocopherol, Magnesium Ascorbyl Phosphate, Lecithin, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Carbomer, Phenoxyethanol, Ethylhexylglycerin, Sodium Hydroxide
Fast & Free Shipping on U.S. Orders Over $75
Order Processing & Shipping
We ship via USPS, UPS, DHL, and FedEx.
Most expedited orders are processed and shipped within 1 business day.
Standard orders containing in-stock items typically ship within 1–3 business days.
Please note that processing times may be extended during promotional events, product launches, holidays, and other periods of high order volume.
Once your order ships, you will receive a shipping confirmation email that includes tracking information. Most U.S. orders arrive within 5–10 business days after shipment, though transit times may vary based on carrier performance and destination.
Our warehouse operates Monday–Friday, 8:00 AM–4:00 PM PST and orders are processed and shipped during business days only.
We strive to process wholesale orders within 48 hours of purchase during our business hours. Please note that processing times may vary during peak shipping periods.
Shipping Delays & Delivery Responsibility
While we strive to ensure timely delivery, shipping timelines may occasionally be impacted by circumstances beyond our control, including but not limited to carrier delays, transportation disruptions, weather events, postal service issues, or other unforeseen circumstances.
Once a shipment has been marked as shipped by the carrier, Truology's fulfillment obligation has been completed. If a package is lost, stolen, or missing after being marked as delivered:
Customers who purchased shipping protection should file a claim directly with the shipping insurance provider.
Customers who declined shipping protection should contact the shipping carrier directly to initiate an investigation or claim.
We appreciate your understanding and are always happy to assist with questions regarding your order status.
Package Protection:
Truology is not responsible for packages that are lost, stolen, or damaged after being successfully delivered to the shipping address provided at checkout.
To help protect your order, we offer Delivery Guarantee powered by Corso during checkout. Corso Shipping Protection provides coverage for packages that are lost, stolen, or damaged in transit.
Customers who decline shipping protection assume full responsibility for any loss, theft, or damage that may occur after the order has shipped. Once an order is transferred to the shipping carrier, responsibility for the shipment passes to the carrier and the recipient.
If you purchased Delivery Guarantee and need to file a claim, the process is quick and easy through Corso:
http://reorder.corso.com/
Incorrect Shipping Address
Please confirm your shipping address is correct before you check out; we do not offer refunds or reships on orders that were shipped to the wrong address and cannot guarantee that an address can be updated once an order has been placed.
If you did not include the correct shipping information and the package is marked as undeliverable or is returned to sender, then the customer is responsible for the $10 shipping fee to reship.
Receipt of Incorrect Product
If you receive the incorrect product in your order, please notify us within 24 hours of delivery. We will provide you with a return label via email to ship the product back to us. Once we receive the returned product, we will immediately inspect and ship the correct product to you.
Returned products must be unopened and unused. If a product is returned, opened and/or used, we are no longer obligated to ship the correct product.
We aim to provide the best service possible but we can sometimes make a mistake and send you the wrong product. It’s never our intention to disappoint our customers and offer our sincerest apologies if this ever happens.
Defective or Damaged Product (USA ONLY)
If a product exchange needs to be made due to a defect, please email us at support@truologyskin.com within 24 hours of receipt to notify us of the defect. A replacement will be sent to you when the original has been received and inspected by our warehouse team This process can take up to 5 business days. Notification of a product defect after the 24-hour period renders the product ineligible for return or exchange. Truology reserves the right to charge a reshipment fee.
If you are covered by Corso Package Protection, claims are easily filed using this link: http://reorder.corso.com/
Refused Packages
Orders returned to us because they were refused are subject to a credit on account after the return has reached us and is deemed unopened and in sellable condition.
A fee of $20 for postage and transaction fees will be deducted from the credit. The package can be reshipped after the postage has been paid.
Freight Forwarding Services
If you ship your order to a freight forwarding company, Truology cannot be held liable for any transaction with the forwarding company. Once delivery is confirmed by the carrier, Truology will no longer be liable for the package. If you purchased Corso Package Protection, their coverage only extends to the shipping address on your order, not any location where it may be forwarded to. Please be aware that items purchased from Truology are only warranted within the United States. All sales to freight forwarders are final. Truology is not liable for any issues from a freight forwarding company.
International Shipping
Outside of the U.S., we currently ship to Australia, Canada, Germany, New Zealand, UK, and Sweden. Non-U.S. customers will be responsible for paying duties and taxes upon receipt of their shipment. We do not charge duties or taxes on checkout.
We do not accept refunds on any international orders. ALL SALES ARE FINAL.
If the shipment is marked as undeliverable, is returned to sender, or you do not pay duties and taxes, 20% of the order value and shipping fees will be excluded from your refund to cover our restocking fee.
Wholesale orders
We do not accept returns on any wholesale orders. All sales are final.
C-Boost: Clinical Levels. Visible Change.
Most Vitamin C Irritates. This One Doesn't.
L-ascorbic acid is notoriously unstable and harsh on sensitive skin — C-Boost was built to deliver the benefits without the sting.
20% Tetrahexyldecyl Ascorbate
A lipid-soluble, highly stable form of vitamin C that penetrates deeply and stimulates collagen synthesis without the irritation of traditional L-ascorbic acid.
15-Antioxidant Defense System
Astaxanthin, ferulic acid, glutathione, ergothioneine, and green tea polyphenols layer broad-spectrum protection against free radicals, UV, and pollution.
"Light, Absorbs Well"
“I have mature, oily, acne prone skin and have found that I just prefer a 20% THD Ascorbate over other forms of Vitamin C. This serum is light, absorbs well and layers very easily with other products.” — Sarah W., verified buyer
Real People, Real Results
I am so impressed with the new barrier restore ultra. It is so hydrating but doesn’t feel heavy at all. The texture is so silky feels amazing on the skin. The ingredients are top tier for anti aging as always. It pairs amazing with the Epicutis SPF definitely recommend.
I absolutely LOVE this new version and this is coming from someone who loved the OG. It's a little richer but in the silkiest way. It feels so good on my skin. I was a little afraid it would be too heavy but I couldn't have been more mistaken. My skin drinks it up immediately and feels more hydrated. Thank you for an even better version! I've never loved moisturizers. I've always preferred serums . . . until now.
This product is VERY good! Love the texture and how it applies. It leaves my skin smooth and glowing. I have noticed a slit disappearance of discoloration of old pimple marks and a small spot of hyperpigmentation i have, fading away. I have purchased a back up, as i would like to see this product continue to work. Consistency is KEY! Great job, Bri! Can't wait for the next product. You and your chemist, are AMAZING!
FANTASTIC serum! Leaves my skin so dewy and hydrated. Too soon to know if it is perfecting my skin, but it looks amazing upon application and feels like my skin becomes more youthful instantly . . . so for this alone, it gets my 5 stars!
Love this product. I apply it every night over my Isdin serum. My skin looks amazing. I get many compliments. I believe the Truology Barrier Restore has improved my skin and gives me a youthful appearance.Published date12/24/25
On my 4/5 bottle of this! Cannot like without this in my routine. Love this product. Zero irritation or dryness and get all the benefits of retinol product. My skin just glows!
I Absolutely Love This Skincare Product and I Absolutely LOVE The New Delivery System Of The Product, Much Better Than The Original Version, Great Product, Great Quality and My Skin Thanks You. I Can’t Remember the Last Time I Had Any Botox, I Get Compliments All The Time On How Great My Skin Is For My 65 Year Old Self And Even People Will Compliment Me In Front Of My Husband Lol 😂
I've used this (alternating with another strong Retinal product) for over a year now and it is one of my favorite Retinal products. I have mature, oily, acne prone skin and am very picky with my skincare regimen. I prefer a stronger strength Retinal and this doesn't cause any irritation. It also plays well with other products and doesn't leave any stain on my white bedlinen.
My favorite vitamin C. I’ve used 2 bottles so far. My skin is brighter and I love all the ingredients in this. The serum layers well with my other products and I use this twice a day. Will keep purchasing
I have mature, oily, acne prone skin and have found that I just prefer a 20% THD Ascorbate over other forms of Vitamin C. This serum is light, absorbs well and layers very easily with other products. No pilling with makeup etc. I love the additional anti-oxidants/actives in the ingredient deck and incorporating this serum (alongside a couple others) into my AM routine. I do find this a little more hydrating so tend to use it more in winter than summer.
I’ve been using C-Boost consistently since they started to ship internationally and I incorporate this product at night with my Truology Vita-A Serum, absolutely Love the new delivery system and I’m hoping that the other products will eventually all be like this, it’s much better than the twist cap, which I did have a couple of the twist caps break on two of my Barrier Creams and One on my Vita-A2 Serum, other than that, my skin has never looked so good and I hardly wear makeup anymore, I feel confident enough to leave my home with no makeup, just a tinted sunscreen.
My skin feels so moisturised, smooth, bright and bouncy with this serum. I could tell pretty much immediately when I added it to my regime. Worth every penny and IMO. This is a new staple for m. Love it!
Won’t be without this product! This is my go to for peptides. It has EVERYTHING my skin loves. Love how I can put it under my eyes as well. My skin is nice and hydrated and stays that way. Not greasy or tacky, just radiant. Brianna, your line is amazing! Ty!
Why Truology Works
High-performance formulations engineered to deliver visible results without unnecessary fillers.
Advanced Peptide Technology
Clinically studied peptides designed to support collagen, elasticity, and long-term skin resilience.
Targeted Active Systems
Each formula is built around a specific concern using proven ingredients like retinaldehyde, tranexamic acid, and THD vitamin C.
Intelligent Delivery
Encapsulated and stabilized actives ensure deeper penetration, better tolerance, and consistent performance.
Clearer, More Even Skin Starts Here
Truology Clear Brightening Glow Serum is a hydroquinone-free, multi-pathway formula designed to visibly reduce melasma, sun damage, and post-acne discoloration while restoring clarity and radiance.
Product FAQ
Vita C3 is a combination of 3 clinically studied vitamin C's, L-Ascorbic acid, THD Ascorbate, and MAP (magnesium ascorbyl phosphate). Truology C-Boost is THD Ascorbate. If you have sensitive skin or are sensitive to L-Ascorbic acid, I would use C-Boost. C-Boost is also great for drier skin types as it's a lipid base and more moisturizing to the skin.
Yes, you can use C-Boost directly under the eyes
No, Vita C3 should not be used directly under the eyes because L-Ascorbic acid can irritate the delicate under-eye skin
Both include peptides and barrier restoring ingredients, but Barrier Restore is lighter on the skin, while Barrier Restore Ultra contains more ceramides, peptides, and also ectoin to further hydrate even the driest skin types. Both products contain everything your skin needs to support a healthy skin barrier, decreasing irritation and inflammation, which leads to a plump and healthy barrier.
You can layer growth factors with the Truology Youth Renew Peptide Serum. Truology Youth Renew uses multiple peptides that perform functions similar to growth factor serums, such as stimulating collagen and elastin, decreasing inflammation, and promoting a healthy skin barrier. Therefore, a growth factor serum is not necessary but can certainly be used alongside Truology.
You don't need to avoid anything; it's great for all skin types.
It is orange due to the high potency of antioxidants but it will not leave a tint on your skin when massaged in. If you are experiencing any tint on your skin it means you are most likely using too much product. Truology is very active and a little goes a long way.
All Truology products are safe for sensitive skin and were formulated for everyone including those with sensitive skin
Please contact us at support@truologyskin.com to inquire about opening a wholesale account.
