The Risks of Overusing Vitamin C in Skincare

Vitamin C has become a powerhouse ingredient in skincare, widely praised for its ability to brighten skin, reduce hyperpigmentation, boost collagen production and protect against free radicals. From serums to moisturisers, its popularity has surged as more people seek radiant, youthful skin.

While Vitamin C benefits the skin in numerous ways, excessive use can lead to irritation, increased sensitivity and even damage to the skin barrier. Understanding how to incorporate it safely is essential to maintaining healthy, resilient skin.

The Best Way to Incorporate Vitamin C into Your Routine

To maximise Vitamin C benefits without experiencing adverse effects, it is important to introduce it properly into your skincare routine:

1. Choosing the Right Concentration
Not all Vitamin C products are created equal, different concentrations cater to different skin types:
• 5–10% formulations are best for sensitive or dry skin, as they provide antioxidant benefits with a lower risk of irritation.
• 10–20% formulations suit normal to oily skin types, offering enhanced brightening and anti-ageing effects.
• Higher than 20% is typically not recommended, as it does not provide significantly greater benefits but increases the likelihood of irritation.

2. Gradual Introduction
When introducing Vitamin C into your routine, start with a low concentration and use it every other day before increasing frequency. This allows the skin to build tolerance and reduces the risk of irritation.

3. Pairing Vitamin C with Sunscreen
Vitamin C enhances sun protection by neutralising free radicals, but it does not replace sunscreen and should never be used with this intention. To prevent sun damage and maximise its benefits, always apply SPF 30 or higher when using Vitamin C in your morning routine.

4. Ideal Skincare Routine Placement
Vitamin C is best used in the morning to protect against daily environmental stressors. Apply it after cleansing and before moisturiser and sunscreen. If using at night, ensure it does not conflict with active ingredients such as retinol or exfoliating acids, which can increase sensitivity.

Risks of Overusing Vitamin C

While Vitamin C can transform the skin, excessive use can lead to several unwanted effects. Overloading the skin with this potent antioxidant may do more harm than good:
• Skin Irritation and Sensitivity
Applying too much Vitamin C or using high concentrations too frequently can cause redness, stinging and itching. This is particularly common in sensitive skin types or when Vitamin C is combined with other strong active ingredients like exfoliating acids.
• Increased Sensitivity to Sunlight
Although Vitamin C provides some photoprotection, overuse can weaken the skin barrier, making it more susceptible to sunburn and damage. This underscores the importance of pairing it with a broad-spectrum sunscreen.
• Disruption of the Skin Barrier
Excessive Vitamin C can compromise the skin’s natural protective barrier, leading to increased dryness, flakiness and inflammation. The skin may become more reactive, making it difficult to tolerate other skincare ingredients.
• Risk of Oxidation

Vitamin C is highly unstable and can oxidise quickly when exposed to air, heat and light. Oxidised Vitamin C may become less effective and, in some cases, could contribute to skin sensitivity or oxidative stress. Signs of oxidation include a colour change in the product, turning from clear or light yellow to dark orange or brown.

How to Identify Overuse and Repair the Skin Barrier

Recognising the signs of Vitamin C overuse is key to preventing long-term damage. If you notice persistent irritation, increased dryness or a compromised skin barrier, it may be time to reassess your usage.

Warning Signs of Overuse:

Overuse of certain skincare products, especially potent ingredients like Vitamin C, can lead to irritation and damage to the skin barrier. Here are key signs to watch for:
• Persistent Redness, Itching, or Burning Sensation: This indicates that your skin is reacting to an ingredient, signalling overuse or sensitivity. If the discomfort continues, it’s important to pause use of the product.
• Increased Skin Sensitivity to Other Products: If your skin starts to react negatively to other products that you typically tolerate well, it may be a sign that the barrier has been compromised by overuse.
• Unusual Dryness or Peeling: Skin becoming excessively dry, flaky, or peeling can be a sign of barrier damage. Overuse of active ingredients can strip the skin of its natural moisture.
• Breakouts or Worsening of Skin Texture: While Vitamin C can help clear up skin, overuse may lead to clogged pores or worsen existing breakouts, causing uneven skin texture.

Steps to Repair the Skin Barrier:

If you’ve noticed any of the above warning signs, it’s essential to take immediate steps to repair your skin’s barrier and restore its health:

1. Reduce Frequency of Use:
• Cut Back: If you’re using Vitamin C daily and experiencing irritation, reduce its frequency to once every few days or switch to a lower concentration. This allows your skin time to recover.
• Reintroduce Slowly: After a break, gradually reintroduce the product back into your routine to ensure your skin tolerates it well.

2. Incorporate Soothing Ingredients:
• Niacinamide: This powerful anti-inflammatory ingredient not only helps to reduce redness and irritation but also strengthens the skin barrier. Niacinamide can also regulate oil production and even out skin tone.
• Ceramides: These lipid molecules are vital for restoring moisture and helping reinforce the skin’s protective outer layer. Ceramides act like the “cement” in your skin’s structure, holding together the skin cells and preventing water loss.
• Hyaluronic Acid: Known for its hydrating properties, hyaluronic acid helps restore moisture and plump the skin, counteracting the dryness that can be caused by overuse of actives. It attracts water to the skin, helping to rehydrate it from within.

3. Avoid Harsh Exfoliants:
• Limit Exfoliating Acids and Retinoids: During recovery, avoid using harsh exfoliating acids (AHAs, BHAs) and retinoids as they can further irritate or damage your skin’s sensitive barrier.
• Opt for a Gentle, Fragrance-Free Moisturiser: Choose a calming, hydrating moisturiser that is free from fragrances and harsh ingredients to help soothe and rebuild the skin barrier without additional irritation. This will provide the hydration and protection your skin needs while it heals.

Balance is Key

Vitamin C is undoubtedly one of the most powerful ingredients in skincare, offering brightening, anti-ageing and protective benefits. However, more is not always better. Overusing Vitamin C can lead to irritation, increased sensitivity and long-term skin barrier damage.

To safely incorporate Vitamin C into your skincare routine:
• Choose a suitable concentration for your skin type
• Introduce it gradually to prevent irritation
• Always pair it with sunscreen for maximum protection
• Watch for signs of overuse and adjust accordingly

By listening to your skin and maintaining a balanced approach, you can enjoy the many benefits of Vitamin C while keeping your skin healthy and resilient. If in doubt, consult a skincare professional at the London Regenerative Institute for expert guidance on products and treatments tailored to your skin’s needs.