Ascorbic acid - how does it work on the skin and does it really rejuvenate?

Why Vitamin C is one of the most overrated and underrated ingredients at the same time

When I first worked on formulating a cosmetic product with vitamin C, everything seemed perfect in theory: a strong antioxidant, anti-aging effects, skin brightening. A "dream ingredient."

In practice?
The product changed color after a few weeks. Skin reacted differently. The effects were... not always what the marketing brochures promised.

And then I understood something very important:

vitamin C is not just one ingredient - it's an entire system of dependencies: form, pH, stability, packaging, and method of application.

That's why some say "it works wonders," while others say "it does nothing."

This article is about organizing facts - without marketing hype.

What is ascorbic acid?

Ascorbic acid (L-ascorbic acid, LAA) is the biologically active form of vitamin C - a water-soluble compound that naturally occurs in the body but is not synthesized by it.

In the skin, it performs several key functions:

• participates in collagen synthesis,
• acts as an antioxidant,
• influences pigmentation.

That's why it found its place in cosmetology.

But also important - not every "vitamin C" in a cosmetic is ascorbic acid.

How does ascorbic acid work on the skin?

1. Stimulation of collagen synthesis

Ascorbic acid is a cofactor for enzymes responsible for collagen production (prolyl- and lysyl-hydroxylase).

Without it:

• collagen fibers are weaker,
• skin loses firmness,
• wrinkles appear faster.

Studies (including Pinnell, Lin) show that regular use of vitamin C increases collagen synthesis in the dermis.

2. Antioxidant action

It is one of the strongest antioxidants used in cosmetics.

Neutralizes:

• free radicals (ROS),
• effects of UV radiation,
• oxidative stress.

In practice, this means slowing down the aging process.

3. Brightening discoloration

Ascorbic acid:

• inhibits tyrosinase activity,
• reduces melanin production.

Effect:

• less discoloration,
• more even skin tone.

4. "Glow" effect

This is the effect that customers notice fastest:

• skin looks fresher,
• less "gray" complexion,
• better light reflection.

Effects of use - what really works and what is marketing

Real effects:

• improvement of skin tone (2–4 weeks),
• brightening of discoloration (4–12 weeks),
• improvement of firmness (8+ weeks).

Marketing myth:
❌ "lifting effect in 7 days"
❌ "instant rejuvenation"

Vitamin C works, but it requires time and a well-chosen formulation.

The biggest problem: instability of vitamin C

This is a key issue and the reason why many cosmetics "don't work."

Why does ascorbic acid oxidize?

• contact with air,
• light,
• high temperature,
• presence of water.

Effect:
👉 it converts into inactive forms.

How do manufacturers try to solve this?

• airless packaging,
• dark glass,
• low pH,
• using more stable forms of vitamin C

And this is where there is a huge difference between a good and an average cosmetic.

Forms of vitamin C - not all work the same way

Pure ascorbic acid (LAA)

• strongest
  – unstable
  – may irritate

Vitamin C derivatives

(e.g., Magnesium Ascorbyl Phosphate - MAP, Sodium Ascorbyl Phosphate - SAP, Ascorbyl Glucoside)

• more stable
• milder
  – weaker action

Which one to choose?

• resilient skin → LAA
• sensitive skin → derivatives
• mature skin → often combinations

How to use ascorbic acid to make it work?

Concentration

• 5% - for beginners
• 10–15% - optimal
• 20% - advanced

pH

For LAA:
👉 below 3.5

Without it:
👉 the ingredient does not penetrate effectively

Morning or evening?

👉 preferably in the morning

Why?

• provides protective action against UV,
• enhances SPF.

What to combine with?

✔ vitamin E
✔ ferulic acid
✔ hyaluronic acid

What not to combine with? (myths)

❌ "do not combine with niacinamide" - MYTH
❌ "do not combine with retinol" - depends, but can be done at different times of the day

For which skin type is it best?

Ideal for:

• dull skin,
• discoloration,
• anti-aging,
• smoker's skin,
• urban skin (pollution).

Can ascorbic acid irritate?

Yes, especially when:

• the concentration is too high,
• the skin barrier is damaged,
• the pH is very low.

How to prevent this:

• introduce gradually,
• combine with hydration,
• do not overdo the concentration.

Ascorbic acid in natural cosmetics - does it make sense?

This is a difficult topic.

Because:

• ascorbic acid itself is not "the problem,"
• the problem is its stability.

Therefore, in natural cosmetics, often:

• its derivatives are used,
• the formula is built around plant antioxidants.

👉 And this approach often yields more stable, predictable results.

How to choose a good vitamin C serum?

Pay attention to:

• packaging (airless > dropper),
• ingredients (whether it's LAA or a derivative),
• presence of supporting antioxidants,
• product freshness

Skincare routine with vitamin C

Morning:

1. gentle cleansing
2. toning (e.g., moisturizing essence)
3. antioxidant serum
4. barrier-strengthening cream
5. SPF

👉 Key: not just vitamin C, but the whole routine

Common mistakes

• too high a concentration to start
• lack of SPF
• poor storage
• using an oxidized product
• combining everything at once

Summary

Ascorbic acid:

• works,
• has huge potential,
• but only when well-formulated and applied.

👉 It's not a "magic ingredient"
👉 It's a tool - which you need to know how to use

More stable alternatives: why vitamin C derivatives often work… better in practice

Due to the low stability of ascorbic acid, it is increasingly replaced by its derivatives in modern formulations. And this is not "taking shortcuts" - it is often a more conscious technological decision.

The most commonly used are:

• 3-O-Ethyl Ascorbic Acid (EAA)
• Ascorbyl Tetraisopalmitate
• Ascorbyl Glucoside

Each of them works differently, but they have a common advantage:
👉 they are more stable, less reactive, and easier to maintain in active form throughout the product's use.

3-O-Ethyl Ascorbic Acid - a compromise that makes sense

This is one of the most interesting forms of vitamin C in cosmetology.

Why?

• it is soluble in both water and partially in lipids → better penetration
• it is much more stable than pure ascorbic acid
• it works without the need for very low pH → lower risk of irritation
• it retains high biological activity

👉 In practice, this means: more predictable effects and fewer "user disappointments."

That's why this form appears in more refined, modern formulations - including Orientana products, where it has been used in:

• serum-ampoules (e.g., brightening and anti-aging lines)
• Orientana Micro-exfoliating Night Cream
• Orientana Hello Papaja Brightening Night Mask
• Orientana Hello Papaja Vitamin C Cream

These formulas are not just about vitamin C itself, but about the entire system:
👉 stability + comfort of use + real effectiveness with regular use

What about other derivatives?

Ascorbyl Tetraisopalmitate
This is a lipophilic form (fat-soluble), which:

• penetrates the stratum corneum very well
• works deeper, but slower
• is exceptionally stable

Often used in anti-aging cosmetics and for dry skin.

Ascorbyl Glucoside

• stable, gentle form
• works more superficially
• ideal for sensitive and beginner skin

👉 Requires conversion in the skin to an active form, so its action is more subtle.

Why is this approach increasingly common today?

Because the truth is:

👉 better stability = a greater chance that the ingredient will actually work on the skin, not just in theory

Pure ascorbic acid may be "the strongest on paper,"
but if it oxidizes after a few weeks — its effectiveness drops to zero.

Therefore, increasingly:

• instead of maximum power → optimal effectiveness over time is chosen
• instead of "a wow effect at the beginning" → real results with long-term use are built

And this is the moment when vitamin C ceases to be overrated —
and simply becomes a well-used tool.

FAQ

1. Is ascorbic acid vitamin C?
   Yes, it is its active form.

2. Does vitamin C work on wrinkles?
   Yes, by stimulating collagen.

3. Can it be used daily?
   Yes, at the appropriate concentration.

4. Does it work on hyperpigmentation?
   Yes, it inhibits tyrosinase.

5. Can it be used in summer?
   Yes, it's even recommended.

6. Morning or evening?
   Preferably in the morning.

7. How long should it be used?
   At least several weeks.

8. Is SPF necessary?
   Yes, it's mandatory.

9. Can it be combined with retinol?
   Yes, but at different times.

10. Can it be combined with niacinamide?
    Yes.

11. Is stinging normal?
    Yes, but it shouldn't be severe.

12. Can it cause allergies?
    Rarely, but it can irritate.

13. Is it suitable for sensitive skin?
    Yes, but in lower concentrations.

14. When do you see effects?
    After 2–4 weeks.

15. Does it give a glow effect?
    Yes.

16. Does it work on acne?
    Indirectly.

17. What pH should the serum have?
    Below 3.5.

18. What concentration is best?
    10–15%.

19. Can the serum oxidize?
    Yes.

20. How to recognize a spoiled serum?
    Change of color.

21. Should it be stored in the refrigerator?
    You can, but it's not necessary.

22. Is light harmful?
    Yes.

23. Does it work on dark circles under the eyes?
    It can help.

24. Can it be used during pregnancy?
    Yes.

25. Can it be used every morning?
    Yes.

Read also Vitamin C and its effect on the skin