Original Cin Niacinamide 10% Serum
Original Cin Niacinamide 10% Serum
Product Description
Product overview
A lightweight, fragrance-free niacinamide serum with 10% vitamin B3, hyaluronic acid, zinc PCA, and organic aloe vera. Designed to minimize pores, fade dark spots, and reduce fine lines while strengthening the skin barrier for a smoother, brighter complexion.
Pore Minimizing
10% niacinamide regulates sebum production and visibly tightens enlarged pores over time.
Texture & feel
SENSORYPore Minimizing
10% niacinamide regulates sebum production and visibly tightens enlarged pores over time.
Dark Spot Correcting
Helps lighten hyperpigmentation, acne scars, and uneven skin tone by reducing inflammation.
Barrier Strengthening
Niacinamide boosts ceramide production, reinforcing the lipid barrier to retain moisture and protect skin.
Deep Hydration
Hyaluronic acid draws moisture into the skin while glycerin and aloe vera soothe and hydrate.
Safety & compatibility
SAFEContains no retinoids, salicylic acid, hydroquinone, or chemical sunscreens. All ingredients are considered safe during pregnancy and breastfeeding.
Free from ferments, fatty acids, esters, polysorbates, and oils that feed malassezia yeast. Safe for fungal acne-prone skin.
Ultra-clean formula with only 9 ingredients. Contains no oils, silicones, or pore-clogging ingredients. Comedogenic rating of 0.
Fragrance-free, alcohol-free, and contains soothing organic aloe vera. Patch test recommended for very reactive skin types.
Can be used with vitamin C, but for best results apply them at different times of day (niacinamide AM, vitamin C PM or vice versa).
Pairs well with retinol. Niacinamide can help buffer irritation from retinol. Apply niacinamide first, then retinol.
Ingredient breakdown
INGREDIENTSNiacinamide (Vitamin B3) 10%Proven
The star active in this serum. Niacinamide is one of the most well-researched skincare ingredients, offering multi-targeted benefits for nearly every skin concern from aging to acne.
- Pore Size: Clinical studies show 10% niacinamide significantly reduces pore appearance after 8-12 weeks of use.
- Anti-Wrinkle: A study (Kawada et al.) found 4% niacinamide reduced wrinkle depth by 9% after 8 weeks; 10% delivers even stronger results.
- Skin Tone: Inhibits melanin transfer to keratinocytes, helping to fade dark spots and even out skin tone.
- Barrier Repair: Boosts ceramide and fatty acid production in the skin, strengthening the lipid barrier.
Zinc PCA ~1-2%Proven
A synergistic combination of zinc and L-pyrrolidone carboxylic acid (PCA). Zinc helps regulate sebum while PCA is a natural moisturizing factor already found in the skin.
- Sebum Control: In-vivo studies show Zinc PCA reduces sebum production statistically significantly after 28 days of daily application.
- Anti-Microbial: In-vitro research demonstrates strong antimicrobial activity against P. acnes bacteria.
- Collagen Support: A 2011 research paper suggests Zinc PCA may promote type I collagen production.
Sodium Hyaluronate (Hyaluronic Acid) <1%Proven
The sodium salt form of hyaluronic acid, which has a smaller molecular size for better skin penetration. Acts as a powerful humectant, drawing moisture into the skin.
- Hydration: Hyaluronic acid can hold up to 1,000 times its weight in water, providing intense hydration.
- Plumping: Attracts water to the upper skin layers, temporarily plumping fine lines and improving skin texture.
Organic Aloe Barbadensis (Aloe Vera) Leaf Juice <1%Promising
Organic aloe vera provides soothing, anti-inflammatory, and hydrating properties. Helps calm redness and irritation while supporting skin healing.
- Anti-Inflammatory: Contains acemannan and other polysaccharides that reduce skin inflammation.
- Wound Healing: Promotes faster skin recovery and repair of damaged tissue.
Glycerin ~3-5%Proven
A well-established humectant and skin-identical ingredient. Draws moisture to the skin and helps maintain the lipid barrier in a healthy state.
- Moisturization: Studies show glycerin is effective from as low as 3%, with even more benefits at higher concentrations for dry skin.
- Barrier Support: Keeps the skin's lipid layers in a healthy liquid crystal state, protecting against irritation.
9 ingredients
Water (Aqua), Niacinamide (Vitamin B3), Glycerin, Phenoxyethanol, Zinc PCA, Sodium Hyaluronate (Hyaluronic Acid), Organic Aloe Barbadensis (Aloe Vera) Leaf Juice, Xanthan Gum, Tetrasodium Glutamate Diacetate
Where it fits in your routine
ROUTINEUse AM and/or PM. Apply after cleansing and toning, before heavier creams. Works well under makeup.
How to use
HOW TO USECleanse
Wash your face with a gentle cleanser and pat dry with a clean towel.
Apply Serum
Dispense 2-3 drops onto fingertips. Gently smooth over face and neck, avoiding the eye area. Allow it to absorb fully.
Moisturize
Follow with your favorite moisturizer to seal in the active ingredients and lock in hydration.
Sun Protection (AM)
In the morning, always finish with a broad-spectrum SPF 30+ sunscreen as the last step.
Who is it for?
WHOPerfect for you if:
- You want to minimize enlarged pores and control excess oil
- You have uneven skin tone, dark spots, or post-acne marks
- You prefer a clean, minimal ingredient list with no fragrance
- You are pregnant or breastfeeding and need safe actives
- You want an affordable niacinamide serum from a small US brand
- You deal with redness, rosacea, or inflamed acne
Consider alternatives if:
- You need a rich, deeply moisturizing serum (this is humectant-only)
- You want additional actives like peptides, ceramides, or retinol in one product
- You prefer a larger bottle size (this is only 1 oz / 30ml)
- You are looking for the absolute cheapest niacinamide option available
Skin type compatibility
SKIN TYPESLightweight gel absorbs instantly with zero greasiness. Zinc PCA helps regulate sebum and niacinamide tightens pores.
Balances oily and dry zones effectively. Hydrates without adding shine, controls oil where needed.
Provides humectant hydration but lacks occlusive ingredients. Pair with a richer moisturizer or facial oil for best results.
Fragrance-free and soothing with aloe vera. Minimal formula reduces irritation risk. Patch test recommended for very reactive skin.
Non-comedogenic (0/5), fungal acne safe, oil-free. Zinc PCA has antimicrobial properties that target acne-causing bacteria.
Results timeline
WEEK 10-12Improved Hydration & Texture
Skin feels softer, smoother, and more hydrated. Hyaluronic acid and glycerin begin to plump the skin. Some users notice an immediate difference in skin texture.
70% noticed softer skinReduced Oiliness & Smaller Pores
Zinc PCA and niacinamide begin regulating sebum production. Pores start to appear visibly smaller and less congested.
60% noticed pore improvementBrighter, More Even Skin Tone
Dark spots and post-inflammatory hyperpigmentation begin to fade. Redness and blotchiness are noticeably reduced. Skin tone appears more uniform.
65% noticed brighter skinVisible Anti-Aging Benefits
Fine lines appear softer as the skin barrier strengthens and ceramide production increases. Overall skin health and resilience are significantly improved.
55% noticed fewer fine linesRatings by platform
300+ REVIEWSPros & cons
BALANCEDPraised
- Ultra-clean formula with only 9 ingredients and no fillers
- Clinically effective 10% niacinamide concentration
- Completely fragrance-free with no essential oils
- Lightweight, non-greasy texture absorbs quickly
- Pregnancy, breastfeeding, and fungal acne safe
- Made in the USA by a small, transparent brand
- Cruelty-free with natural and organic ingredients
- Works well under makeup and with other actives
Criticized
- Small 1 oz (30ml) bottle runs out fast for daily use
- Higher price per ounce compared to mass-market alternatives
- Humectant-only formula requires a separate moisturizer
- No additional actives like ceramides or peptides
- Limited availability outside of Amazon and brand website
- Minimal packaging design may not appeal to everyone
Budget-friendly alternatives (dupes)
DUPESSame 10% niacinamide and zinc PCA actives. Lacks hyaluronic acid and aloe vera. Slightly thicker texture. Contains pentylene glycol instead of glycerin. Not organic-focused but extremely affordable.
Higher niacinamide (12%) and zinc (2%) concentrations. Includes hyaluronic acid, vitamin E, and dimethicone. More complex 16-ingredient formula. Not organic-focused but clinically tested.
Lower niacinamide concentration (undisclosed %). Includes ceramides and peptides for additional barrier support. Much more complex formula. Developed with dermatologists but contains more synthetic ingredients.
Comparison with competitors
SIDE-BY-SIDEStorage & shelf life
12 MONTHS12 months after opening
Store in a cool, dry place away from direct sunlight. No refrigeration needed.
Squeeze tube with twist cap. Hygienic dispensing with minimal air exposure.
Yes, 1oz (30ml) is under the 100ml TSA / airport security limit.
Frequently asked questions
FAQYes. This serum contains no retinoids, salicylic acid, hydroquinone, chemical sunscreens, or any other ingredients flagged as unsafe during pregnancy and breastfeeding. Niacinamide, hyaluronic acid, glycerin, and aloe vera are all considered safe for use during pregnancy and while nursing. As always, consult your healthcare provider if you have specific concerns.
Yes. The formula is completely free from ferments, fatty acids (like oleic or lauric acid), fatty acid esters, polysorbates, and oils that are known to feed malassezia yeast. With only 9 clean ingredients, this is one of the safest niacinamide serums for fungal acne-prone skin.
Yes, niacinamide pairs well with most actives. With retinol, apply niacinamide first to buffer potential irritation. With vitamin C, some research suggests using them at different times of day for optimal results (e.g., niacinamide in AM, vitamin C in PM), though using them together is generally safe. With AHA/BHA exfoliants, apply the acid first on clean skin, wait a few minutes, then layer niacinamide on top.
This serum works for all skin types but is especially excellent for oily, combination, and acne-prone skin. The zinc PCA helps control excess oil while niacinamide minimizes pores. Dry skin types will benefit from the hydrating ingredients but should layer a richer moisturizer on top. Sensitive skin types will appreciate the minimal, fragrance-free formula.
Improved hydration and texture are typically noticeable within the first 1-2 weeks. Reduced oiliness and smaller-looking pores usually appear around weeks 3-4. Significant improvements in skin tone, dark spots, and fine lines require consistent use for 8-12 weeks. Results vary by individual and skin concern.
Apply after cleansing and toning, before heavier creams and moisturizers. The lightweight gel texture should go on before thicker products. In the morning: cleanser, toner, this serum, moisturizer, SPF. In the evening: cleanser, toner, this serum, treatment (retinol if used), moisturizer. It works well under makeup.
No. This serum has a comedogenic rating of 0 out of 5. It contains no oils, silicones, waxes, or other pore-clogging ingredients. With only 9 ingredients and an oil-free, water-based formula, it is one of the safest serums for acne-prone and congestion-prone skin.
The serum has a Period After Opening (PAO) of approximately 12 months. Store in a cool, dry place away from direct sunlight. The 1oz (30ml) bottle typically lasts 4-8 weeks with twice-daily use (2-3 drops per application). Look for any changes in color, consistency, or smell as signs of expiration.
Verdict: Eight Saints Original Cin is a clean, minimal niacinamide serum that delivers proven actives in a no-nonsense formula. Its standout strength is the ultra-short, transparent ingredient list — just 9 ingredients with no fragrances, silicones, or unnecessary fillers. The 10% niacinamide, zinc PCA, and hyaluronic acid combination is clinically effective for pore reduction, oil control, and brightening. It scores perfectly for pregnancy safety, fungal acne safety, and comedogenicity. The main drawback is the premium price for a small 1oz bottle, especially when budget alternatives like The Ordinary offer similar key actives at a fraction of the cost. Best suited for clean beauty enthusiasts who value minimal formulations, organic ingredients, and supporting small US-based brands.
Product Overview
Quick product notes are a great way to check if a product is free from commonly avoided ingredients by skincare enthusiasts. These preferences come about for different reasons depending on the ingredient such as personal experiences, sensitivities, health preferences & etc.
Just because a product is not free from a common preference does not mean it's a bad product! You can make a personal decision whether or not you want to use a product that contains these ingredients or not - click the labels of the preference to read more about them.
Quick Product Notes
Ever used a product that promised a certain effect but provided no results? It might not have contained any notable ingredients that could have been responsible for that promised effect. It doesn't matter what the marketing or packaging «promises» it can do, if it doesn't contain anything that can help - then the likelihood of it helping is low.
We help you identify key notable ingredients that have been shown to help with effects such as acne-fighting, brightening, UV-protection, wound healing & anti-aging to help you achieve your skincare goals smarter. Please note that different notable ingredients have varying levels of research behind them, some are extremely well proven yet some have mixed research in their efficacy.
Just because a product doesn't contain any notable ingredients doesn't mean it's bad. And a product with notable ingredients (or even many) doesn't necessarily guarantee the efficacy of the product performing these effects either. There are other factors such as ingredient quality, concentration and formulation that will ultimately determine this.
Be smart and use this as just a starting point for you to make more informed and smarter choices and compare it with reviews to see if the product is right for you
Notable Effects & Ingredients
Why are some products great for some people and horrible for others? Well everyone has different skin types and different reactions to the same ingredients.
We've identified a range of ingredients that are commonly regarded as potentially good or bad for those with Dry, Oily/Acne-Prone or Sensitive skin.
A product that contains good or bad ingredients for your skin type doesn't always flat out make the entire product good or bad for your skin. There are other factors such as ingredient quality, concentration and formulation that will ultimately determine your skins reaction.
One of the best ways to use this section is to troubleshoot products you've had bad experiences with in the past. Check if it contains any of the marked ingredients to point out suspect ingredients to avoid in the future!
Ingredients Related to Skin Types
Ingredient Safety Breakdown refers to the percentage % of ingredients in different risk categories as classified by EWG (Environment Working Group) if they are available. There are almost endless cosmetic ingredients and they are one of the few organisations globally that have assigned ratings to a lot of the more commonly used ingredients which is why we reference them.
EWG is seen by many to be more on the alarmist side in their assignment of health ratings resulting in rating ingredients as riskier than they actually are. We recommend using this a reference point rather than a strict guide of ingredient safety and to always do further research if into ingredients that you may find suspect.
Ingredient Safety Breakdown
Product ingredient list
| EWG | CIR | Ingredient Name & Cosmetic Functions | Notes |
|---|---|---|---|
| 1 |
Water
Solvent, Skin Conditioning
|
|
|
| 1 |
Niacinamide
Skin Conditioning, Hair Conditioning, Smoothing
|
Promotes Wound Healing
Redness
Irritation
Dark Spots
Pores
|
|
| 2 |
Glycerin
Solvent, Perfuming, Fragrance, Humectant, Viscosity Decreasing Agent, Hair Conditioning, Skin Protecting, Denaturant, Skin Conditioning
|
Promotes Wound Healing
Hydrating
|
|
| 4 |
Phenoxyethanol
Fragrance, Preservative
|
|
|
| 0 |
Zinc PCA
|
Promotes Wound Healing
Redness
|






