C20 Renewal: TIAM My Signature C Source Serum

by - October 15, 2017

Hello Lovelies

After reviewing Nature Republic Aloe Vera Gel (here), I decided to talk next about a product that I've been using for 3-4 years now (and made many other people try it and love it as much as I do along the way): Tiam My Signature C Source (Formerly known as OST Original Pure Vitamin C20 Serum) 

Description and claims:

100% Pure vitamin for remarkable, healthy skin.
My Signature C Source Serum contains about 6,000mg of 100% Pure Vitamin C. It contains 20% concentration of L-Ascorbic acid, which maximize the benefits, and additional feature of peeling function. As natural antioxidants, it helps prevent premature signs of again, while it protects, softens, and moisturizes your skin. 
High portion of Vitamin C and still remarkably safe.
22.9% of Original Pure Vitamin C20 Serum is the real meaning of pure Vitamin C. One bottle of My Signature C Source contains vitamin c 40 times more than orange, 120 times more than strawberries and 200 times more than Mandarines. 
Proved Effectiveness.
My Signature C Source Serum not only offers whitening, exfoliation and pore care effect, but also helps smooth the rough area on your skin, caused by spots or acne breakouts, when used regularly or long term. After using the serum, research shows positive result on skin condition. Out of 2075 respondents, who used My Signature C Source Serum :
- 97.91% said, Skin looked brighter and more defined complexion.
- 96.00% said, The serum reduced unwanted skin pigmentation and blemishes.
- 92.20% said, Positive skin improvement after first usage.
- 86.52% said, The serum smoothens out uneven texture.
Source: Wishtrend

Volume: 30 ml

Water, Ascorbic Acid, Alcohol, Sodium Lactate, Butylene Glycol, Glucose, PEG-60 Hydrogenated Castor Oil, 1,2-Hexanediol, Phenoxyethanol, Sodium Hyaluronate, Bis-PEG-18 Methyl Ether Dimethyl Silane, Xanthan Gum, Diethoxyethyl Succinate, Ammonium Acryloyldimethyltaurate/VP Copolymer, Carthamus Tinctorius (Safflower) Flower Extract, Citrus Aurantium Dulcis (Orange) Peel Oil, Glycerin, Zinc PCA, Panthenol, Niacinamide, t-Butyl Alcohol, Camellia Sinensis Leaf Extract, Beta-Glucan, Tocopheryl Acetate, Lecithin, Caprylic/Capric Triglyceride, Ubiquinone, Diisopropyl Adipate

How to use:
- After applying toner, spread the C source on the areas with tired and stressed skin.
- You can also mix one or two drops of the C source with your toner.
- Make sure to use sunblock when going outside after applying C source.
- After C source, apply a moisturizing product for a better effect.

- It is best to keep this product out of direct sunlight and high temperatures, as this will damage the product. (tip: store it in the fridge to keep it fresh longer)
- When you use this product, please avoid using any product containing high levels of AHA, BHA or Retinal.

First of all, I wanna say that I'm in love with its orange box since I love orange and I love how it has that metallic effect (but unfortunately I couldn't catch it with my phone's camera)

The pics say everything lol, the only thing I would like to add is that you should make sure that the bottle stays in a vertical position, otherwise the product may leak out of it (like mine) and have an orange sticky mess inside of the box...

As you can see, nothing changed except for the name and the brand.

The serum: Swatches, scent...

The serum smells like burnt oranges, it has a light color (that oxidizes later and turns into a yellow-orangish color, and if you leave it for a long long time in a warm area or in contact with air, it would become kinda brown like the picture below)

This serum is a bit thicker and stickier than the other serums, and takes a longer time to be absorbed. I usually use it directly after toning and leave it for about 15 min before the next step in my night routine, this way I make sure it fully does its work since the Ascorbic Acid is easily influenced by the skin's pH, and it won't work if it's too high.

Once a week, I apply this serum and right after it use a C21.5 Sheet mask to maximize the effects.
You may as well add it to your other skincare products if you want, but I personally prefer using it alone to prevent any unwanted chemical reactions.

And now let's move to the results... I believe that my skin loved it.
Here is a pic of my skin during spring, when it usually becomes really crazy, irritated by almost everything. I usually avoid chemicals and opt for aloe vera and rose water, but after trying this product, I realized that Vitamin C is what my skin actually needs. See for yourself what I'm talking about:

I didn't lie when I said that my skin loved it. The before picture is the one I took right after using it for the first time (that's how awful my skin looks during spring...), and the other pic is how my skin looked after  about a week or so of using it regularly on daily basis. A big difference I know...
I can't judge if it reduced my blackheads since I have really tiny ones and use nose patches often (and my blackheads are still like they were the first day I started using this serum), and I don't think the it brightened my skin tone since I already have a fair skin tone (I'm somewhere around NC10).


- A really affordable price.
- Highly effective against acne and acne scars.
- Improves skin texture.
- Nice orange box (I love it what?) and packaged in a dark bottle to delay its oxidation.
- Contain a high amount of vitamin C (the 2nd higher amount I've ever seen after c21.5)
- My skin tend to secrete a bit more sebum than usual, which is good for my dehydrated skin.

- Leaked when the bottle is left horizontally.
- Sticky

You can buy it:
- at Wishtrend* for $14.99 (use my invitation code: 125028803 to get $5 off your first $30 purchase)

Would I repurchase it?
Is that even a question? I've been using it for years and  I'm not planning to change that any time soon.

Don't forget to follow me on social media for more updates ^_^ 

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  1. After apply serium night time can I apply my night whiting cream?

    1. If your whitening cream contains niacinamide, it would be better to use it separately from this serum, since using them together tends to neutralize their effects

  2. Those results are really impressive!

  3. Thank you so mush for the review,I have a question, you said to avoid using it with products containing high levels of AHA or BHA, I'm currently using the COSRX BHA BLACKHEAD POWER LIQUID, so I can't use this serum at all ? or can I use one of them in the daytime skincare routine and the other one in the nighttime routine ?

    1. COSRX AHA, BHA and PHA products don'tcontain a high level of active (since the Korean government have regulated the actives use and obliged all the brands to lower their BHA and AHA levels)
      I personally use them at the same time, but since your skin isn't used to them used together, you can either use one of them in the morning and the other at night (don't forget your sunscreen), use them separately each one a day (especially if you have a sensitive skin), or introduce this serum gradually to your skincare routine, by using it twice a week at first, then go up from there gradually while keeping an eye on how your skin reacts to this new addition, and which rate is better for your skin.
      Hope this was helpful :*

    2. It's definitely helpful thank you.

  4. Wow the Tiam My Signature C Source really works I will consider to give it a try.

    1. hopefully it would work well on u as well ^^