# 111SKIN Y Theorem Repair Light Serum NAC Y2 for dry sensitive skin

**Lovi Fit: Average fit for dry sensitive skin.**
Dry Skin Fit: Average · Effectiveness: Average · Safety: High.

Page: https://lovi.care/skincare/sa/p/111skin/y-theorem-repair-light-serum-nac-y2/for/dry-sensitive-skin

The Lovi Fit is the same in every country; only the stores and prices differ, and the ones here are for Saudi Arabia.

Brand: [111SKIN](https://lovi.care/skincare/sa/brands/111skin)
Category: [Serums and treatments](https://lovi.care/skincare/sa/best/serums)

This fit is calculated for the concerns frequently associated with dry sensitive skin: flakiness, tightness, redness, fine lines, and wrinkles. For scores based on a full skin profile (12D face scan, goals, preferences), use the Lovi app.

Works for dry sensitive skin; other serums fit it better.

## Why this fit

- Offers moderate suitability for your dry and sensitive skin as glycerin and aloe barbadensis extract provide hydration and calming effects, while niacinamide and sodium ascorbyl phosphate help with evening skin tone and reducing blemishes.
- Panthenol offers humectant action, but the formula lacks sufficient emollient ingredients like Prunus Armeniaca Kernel Oil to fully address your dryness.
- The product is safe for your skin due to the absence of prohibited or harsh ingredients, posing no risk of irritation.

## Fit by skin type

- [Oily skin](https://lovi.care/skincare/sa/p/111skin/y-theorem-repair-light-serum-nac-y2/for/oily-skin): Average
- [Dry skin](https://lovi.care/skincare/sa/p/111skin/y-theorem-repair-light-serum-nac-y2/for/dry-skin): Average
- [Combination skin](https://lovi.care/skincare/sa/p/111skin/y-theorem-repair-light-serum-nac-y2/for/combination-skin): Average
- [Sensitive skin](https://lovi.care/skincare/sa/p/111skin/y-theorem-repair-light-serum-nac-y2/for/sensitive-skin): Average
- [Acne-prone skin](https://lovi.care/skincare/sa/p/111skin/y-theorem-repair-light-serum-nac-y2/for/acne-prone-skin): Average
- [Skin with dark spots](https://lovi.care/skincare/sa/p/111skin/y-theorem-repair-light-serum-nac-y2/for/dark-spots): Average
- [Mature skin](https://lovi.care/skincare/sa/p/111skin/y-theorem-repair-light-serum-nac-y2/for/mature-skin): Average
- [Dry sensitive skin](https://lovi.care/skincare/sa/p/111skin/y-theorem-repair-light-serum-nac-y2/for/dry-sensitive-skin): Average (this page)
- [Oily acne-prone skin](https://lovi.care/skincare/sa/p/111skin/y-theorem-repair-light-serum-nac-y2/for/oily-acne-prone-skin): Average

## Key ingredients

Nac Y2, Niacinamide, Calendula Officinalis Extract, Aloe Barbadensis Extract, Acetyl Cysteine

## What the research says

- Niacinamide significantly decreased hyperpigmentation and increased skin lightness compared with vehicle alone after 4 weeks of use in women by inhibiting melanosome transfer. ([The British Journal of Dermatology, 2002](https://pubmed.ncbi.nlm.nih.gov/12100180/))
- A single application of a moisturizing fluid containing hyaluronic acid 1%, glycerin 5%, and Centella asiatica stem cells extract significantly increased skin hydration by 29% and reduced transepidermal water loss at 24 hours compared to baseline and an untreated control site in twenty healthy women. ([Clinical, Cosmetic and Investigational Dermatology, 2017](https://pubmed.ncbi.nlm.nih.gov/28860834/))
- Topical combination of 5% sodium ascorbyl phosphate and 0.2% retinol reduced inflammatory acne lesions by 29.28% at 4 weeks and 63.10% at 8 weeks, outperforming either agent alone. ([International Journal of Cosmetic Science, 2009](https://pubmed.ncbi.nlm.nih.gov/19134126/))
- Topical dexpanthenol acts as a moisturizer, improves stratum corneum hydration, accelerates wound healing and epidermal regeneration, reduces erythema, and improves symptoms of skin irritation compared to vehicle or no pretreatment. ([American Journal of Clinical Dermatology, 2002](https://pubmed.ncbi.nlm.nih.gov/12113650/))
- Glutathione amino acid precursors effectively increase cellular glutathione levels, reducing oxidative stress, ATP depletion, and DNA damage in human keratinocytes, clinical subjects, and ex vivo skin compared to controls. ([Journal of the European Academy of Dermatology and Venereology, 2024](https://pubmed.ncbi.nlm.nih.gov/38189670/))
- Topical glutathione improves hyperpigmentation, reduces ultraviolet-induced erythema and wrinkles, decreases transepidermal water loss, and enhances antioxidant capacity. ([The Journal of Clinical and Aesthetic Dermatology, 2025](https://pubmed.ncbi.nlm.nih.gov/41416233/))
- RayGel reduced skin reaction severity with a lower average score of 93.7 compared to 123.3 for the placebo group in patients undergoing whole breast external-beam irradiation. ([American Journal of Surgery, 2005](https://pubmed.ncbi.nlm.nih.gov/15862509/))
- Topical post-laser application of human adipocyte-derived mesenchymal stem cell media combined with niacinamide significantly improved wrinkle index, melanin index, patient satisfaction, and investigator esthetic improvement scores compared to vehicle cream in patients with aging skin. ([Journal of Cosmetic Dermatology, 2021](https://pubmed.ncbi.nlm.nih.gov/33103316/))
- Topical nicotinamide prevented solar-simulated UV-induced immunosuppression in healthy volunteers, and men experienced immunosuppression at solar-simulated UV doses three times lower than those required for women. ([The Journal of Investigative Dermatology, 2008](https://pubmed.ncbi.nlm.nih.gov/17882270/))
- Topical 5% niacinamide applied twice daily for 12 weeks reduced fine lines and wrinkles, hyperpigmented spots, red blotchiness, and skin sallowness, and improved skin elasticity compared to vehicle control in 50 female white subjects with facial photoaging. ([Dermatologic Surgery, 2005](https://pubmed.ncbi.nlm.nih.gov/16029679/))
- Topical application of Calendula officinalis extract cream significantly improved skin hydration and firmness (reflected in significant changes in R0 and R6 parameters) in 21 healthy human volunteers compared to a base cream. ([Acta Poloniae Pharmaceutica, 2011](https://pubmed.ncbi.nlm.nih.gov/21928714/))
- Treatment with standardized extract of Calendula officinalis L. led to a shorter epithelization time and faster healing speed compared to mineral oil in patients with acute skin loss wounds of the hand and fingers healing by secondary intention. ([Tissue Barriers, 2022](https://pubmed.ncbi.nlm.nih.gov/34674610/))
- Topical administration of Calendula provides weak evidence of effectiveness in acute and chronic wounds compared to standard treatments based on a narrative review of available trials. ([Wounds, 2008](https://pubmed.ncbi.nlm.nih.gov/25941793/))
- A cream combining propolis, tea tree oil, and Aloe vera reduced erythema scars, acne severity index, and total lesion count better than erythromycin cream in sixty patients with mild to moderate acne vulgaris compared to placebo. ([Clinical Pharmacology, 2018](https://pubmed.ncbi.nlm.nih.gov/30588129/))
- Topical aloe vera gel significantly accelerated split-thickness skin graft donor-site healing compared to placebo in 12 patients, but showed no significant difference in pain relief. ([Plastic and Reconstructive Surgery, 2018](https://pubmed.ncbi.nlm.nih.gov/29649056/))
- Topical application of Aloe vera cream reduced postoperative pain at rest and during defecation, accelerated wound healing at two weeks, and decreased analgesic requirements in patients after open hemorrhoidectomy compared to placebo. ([Journal of Alternative and Complementary Medicine, 2010](https://pubmed.ncbi.nlm.nih.gov/20569031/))
- Topical N-acetylcysteine plus doxycycline achieved significantly greater improvements in total lesion count, inflammatory lesion count, IGA, GAGS, and CADI scores compared to benzoyl peroxide plus doxycycline in 40 patients with moderate acne vulgaris. ([Dermatology Practical & Conceptual, 2026](https://pubmed.ncbi.nlm.nih.gov/42190184/))
- Topical application of alpha-tocopherol, l-ascorbic acid, alpha-lipoic acid, glutathione ethylester, and N-acetylcysteine decreased UVB-radiation-induced cell death, apoptosis, and lipid peroxidation in ex vivo pig skin explants compared to untreated controls. ([Radiation Research, 2003](https://pubmed.ncbi.nlm.nih.gov/12537526/))
- Topical vitamin C, vitamin E, and acetylcysteine showed similar effects on the healing of experimentally created corneal wounds in rabbits, with no statistically significant differences compared to each other. ([Indian Journal of Ophthalmology, 2020](https://pubmed.ncbi.nlm.nih.gov/33229673/))

## Why other serums fit dry sensitive skin better

- Tocopherol succinate-loaded ethosomal gel increased skin deposition, stability, moisture, and mechanical properties in 13 human subjects compared to a control gel over 12 weeks. ([Journal of Cosmetic Dermatology, 2022](https://pubmed.ncbi.nlm.nih.gov/35274433/))
- In 50 participants with sensitive skin, a Ceramide NP C15-containing emollient improved skin barrier function with a significant reduction in transepidermal water loss and induced modest changes in skin microbiota compared to the vehicle. ([Skin Pharmacology and Physiology, 2026](https://pubmed.ncbi.nlm.nih.gov/41758783/))
- Hydrogels containing vitamin E-loaded nanostructured lipid carriers exhibited better occlusive properties and long-lasting effects, while vitamin E-loaded nanoemulsions performed a faster skin hydration effect and were selected as more attractive for skin application. ([Colloids and Surfaces. B, Biointerfaces, 2019](https://pubmed.ncbi.nlm.nih.gov/30974262/))

## What reviewers say

Users with oily, combination, or humid-climate skin praise the serum's lightweight, water-like texture for providing deep hydration without greasiness, often noting significant improvements in redness, inflammation, and post-procedure healing. A notable portion of reviewers feel the extremely high price point is unjustified, citing strong fragrance and a lack of dramatic anti-aging results as key drawbacks compared to more affordable alternatives.

- Liked: Lightweight & fast-absorbing (mostly mentioned)
- Disliked: Extremely expensive (mostly mentioned)
- Liked: Hydrating & plumping (often mentioned)
- Liked: Soothing & healing (often mentioned)
- Liked: Good for oily skin (sometimes noted)
- Disliked: Lack of visible results (sometimes noted)
- Disliked: Strong fragrance (sometimes noted)
- Disliked: Potential irritation (rarely noted)

## How to apply

- Use this PM routine for your evening skincare. Start using the serum 3 times a week and increase to daily use if your skin feels comfortable.
- Apply the serum after cleansing and toner, but right before your moisturizer. This step locks in deep hydration for dry skin.
- Gently press 2-3 drops of the serum into your skin using your palms. Let it absorb completely for a minute ⏱ before applying your next product.
- Since your skin is sensitive, apply the serum on completely dry skin for better tolerance and less irritation.
- Avoid the sensitive eye area during application. Always do a patch test before your first use to ensure your skin reacts well.
- Video: https://storage.pora.ai/c879dda8655a61c19d3d8c9ebad6b06d.mp4

## Questions and answers

### How well does 111SKIN Y Theorem Repair Light Serum work for dry sensitive skin?

This serum offers moderate suitability for your dry sensitive skin as glycerin and aloe provide hydration and calming effects, while niacinamide helps even skin tone. However, the formula lacks sufficient softening ingredients to fully address your dryness. A product of this type needs rich moisturizing and nourishing components to deliver deep hydration and support the skin barrier.
Sources: [The British Journal of Dermatology, 2002](https://pubmed.ncbi.nlm.nih.gov/12100180/), [Clinical, Cosmetic and Investigational Dermatology, 2017](https://pubmed.ncbi.nlm.nih.gov/28860834/)

### Which ingredients make this serum a good fit for dry sensitive skin?

Glycerin and aloe leaf extract make this serum a good fit by providing hydration and calming effects for your dry and sensitive skin. Panthenol also helps retain moisture, while niacinamide and sodium ascorbyl phosphate help even your skin tone and reduce blemishes.
Sources: [Clinical, Cosmetic and Investigational Dermatology, 2017](https://pubmed.ncbi.nlm.nih.gov/28860834/), [American Journal of Clinical Dermatology, 2002](https://pubmed.ncbi.nlm.nih.gov/12113650/)

### What does Nac Y2 do for dry sensitive skin?

NAC Y2 helps soothe and protect dry sensitive skin by calming irritation and fighting oxidative stress. This ingredient is unlikely to cause trouble and works to keep your skin feeling comfortable and smooth.
Sources: [Antioxidants, 2026](https://pubmed.ncbi.nlm.nih.gov/42650255/)

### What does Niacinamide do for dry sensitive skin?

Niacinamide helps dry sensitive skin by calming irritation and keeping moisture locked in so your face feels soft and smooth. It works to build up your skin barrier and calm redness while being very gentle and unlikely to cause irritation.
Sources: [Journal of Cosmetic Dermatology, 2004](https://pubmed.ncbi.nlm.nih.gov/17147561/), [International Journal of Pharmaceutics, 2013](https://pubmed.ncbi.nlm.nih.gov/23220080/)

### Where does this serum go in a skincare routine for dry sensitive skin?

This serum goes in the evening routine after cleansing and toning, and before moisturizing. It works for your dry sensitive skin by providing hydration and calming effects, though a product of this type needs more rich nourishing oils to fully address your dryness.

### Can I use this serum with retinol, and in what order?

You can use this treatment in your evening routine after your soothing toner and before your moisturizer, but apply your retinol on alternate nights or consult a professional to avoid irritation. This product is unlikely to irritate your skin due to the absence of harsh ingredients, though a product for dry and sensitive skin also needs rich oils and heavy moisturizers to fully address dryness.

### How often should I use this serum?

You can use this treatment in the evening as part of your routine. While it offers moderate hydration and calming effects, dry skin needs additional rich softening ingredients and heavier oils to fully address dryness.
Sources: [Clinical, Cosmetic and Investigational Dermatology, 2017](https://pubmed.ncbi.nlm.nih.gov/28860834/)

### Can this serum clog pores, cause breakouts or purging for dry sensitive skin?

This serum is unlikely to cause breakouts or clog pores on dry sensitive skin, as it contains no harsh or prohibited ingredients that trigger irritation. A product of this type needs richer softening ingredients and oils to properly comfort and nourish dry skin.

### Is this serum fragrance-free and alcohol-free?

It contains fragrance (benzyl alcohol and parfum) and drying alcohol (alcohol).

## Alternatives for dry sensitive skin

- [SkinCeuticals C E Ferulic](https://lovi.care/skincare/sa/p/skinceuticals/c-e-ferulic/for/dry-sensitive-skin) — Superior fit — SAR 865.37 at Amazon
- [Paula's Choice RESIST Super Antioxidant Concentrate Serum](https://lovi.care/skincare/sa/p/paula-s-choice/resist-super-antioxidant-concentrate-serum/for/dry-sensitive-skin) — Superior fit — SAR 461.00 at Amazon
- [Beauty of Joseon Propolis + Niacinamide Glow Serum](https://lovi.care/skincare/sa/p/beauty-of-joseon/propolis-niacinamide-glow-serum/for/dry-sensitive-skin) — Superior fit — SAR 226.83 at Amazon

## Pairs well with

- Cleanser: [Illiyoon Ceramide Derma Amino Cleansing Foam](https://lovi.care/skincare/sa/p/illiyoon/ceramide-derma-amino-cleansing-foam/for/dry-sensitive-skin) — Superior fit — SAR 149.44 at Amazon
- Soothing Toner: [Clarins Toning Lotion with Camomile](https://lovi.care/skincare/sa/p/clarins/soothing-toning-lotion/for/dry-sensitive-skin) — Superior fit — SAR 141.00 at Amazon
- Moisturizer with Sun Protection: [d'Alba UVessence Mild Waterfull Sun Cream SPF 50](https://lovi.care/skincare/sa/p/d-alba/uvessence-mild-waterfull-sun-cream-spf-50/for/dry-sensitive-skin) — Superior fit — SAR 89.00 at Amazon

## Where to buy

- Amazon.sa: SAR 989.20 (https://www.amazon.sa/dp/B00U3CWDUK?tag=lovisa02-21&linkCode=osi&th=1&psc=1)
Prices checked 5 Nov 2026.

## Ingredients

Water, Glycerin, Alcohol, Benzyl Alcohol, Aloe Barbadensis Extract, Calendula Officinalis Extract, Carbomer, Sodium Hydroxide, Aesculus Hippocastanum Extract, Sodium Ascorbyl Phosphate, Panthenol, Niacinamide, Thiamin, Riboflavin, Pyridoxine, Cyanocobalamin, Glycyrrhiza Glabra Root Extract Licorice Root Extract, Prunus Armeniaca Kernel Oil Apricot Kernel Oil, Acetyl Cysteine, Parfum
## About the Lovi Fit

Lovi: Unbiased, science-based skincare AI trained on real user outcomes.

Lovi calculates every fit score from the full ingredient list with brand-independent rules its dermatologists and cosmetic chemists build and review, and personalizes every pick with AI trained on the real results of millions of users. Lovi trains its fit score models on a proprietary dataset built from more than 10,000 expert-labeled products and more than 100,000 simulated examples, following an internally consistent methodology presented at Cosmoprof, AMWC, and Skin of Color Update. Levels from best to worst: Superior, High, Average, Low, Caution, Warning.

Behind this fit score: Nadia Kapleva, MS (Co-founder, Medical Director); Alexey Shagraev, PhD (Co-founder, CEO and CTO); Dr. Sofía Perea Pérez, MD, MSc (Medical Board); Aishani Shah, MD (Medical Board); Asya Zubkova, MS (Medical Board); Hanna Kurets, MD (Medical Board, Medical Advisor); Elina Nazarenko, MD (Medical Board); Victoria Derkova, MS (Medical Board).

Page built Nov 8, 2026.

More from Lovi: https://lovi.care/skincare/llms.txt

## This page in other countries

- United States: https://lovi.care/skincare/p/111skin/y-theorem-repair-light-serum-nac-y2/for/dry-sensitive-skin
- United Kingdom: https://lovi.care/skincare/uk/p/111skin/y-theorem-repair-light-serum-nac-y2/for/dry-sensitive-skin
- Ireland: https://lovi.care/skincare/ie/p/111skin/y-theorem-repair-light-serum-nac-y2/for/dry-sensitive-skin
- Germany: https://lovi.care/skincare/de/p/111skin/y-theorem-repair-light-serum-nac-y2/for/dry-sensitive-skin
- France: https://lovi.care/skincare/fr/p/111skin/y-theorem-repair-light-serum-nac-y2/for/dry-sensitive-skin
- Italy: https://lovi.care/skincare/it/p/111skin/y-theorem-repair-light-serum-nac-y2/for/dry-sensitive-skin
- Netherlands: https://lovi.care/skincare/nl/p/111skin/y-theorem-repair-light-serum-nac-y2/for/dry-sensitive-skin
- Spain: https://lovi.care/skincare/es/p/111skin/y-theorem-repair-light-serum-nac-y2/for/dry-sensitive-skin
- Canada: https://lovi.care/skincare/ca/p/111skin/y-theorem-repair-light-serum-nac-y2/for/dry-sensitive-skin
- Australia: https://lovi.care/skincare/au/p/111skin/y-theorem-repair-light-serum-nac-y2/for/dry-sensitive-skin
- Singapore: https://lovi.care/skincare/sg/p/111skin/y-theorem-repair-light-serum-nac-y2/for/dry-sensitive-skin
- Saudi Arabia: https://lovi.care/skincare/sa/p/111skin/y-theorem-repair-light-serum-nac-y2/for/dry-sensitive-skin (this page)
- United Arab Emirates: https://lovi.care/skincare/ae/p/111skin/y-theorem-repair-light-serum-nac-y2/for/dry-sensitive-skin