Skin Mentor Sandra Knight reveals why post-acne marks and dark spots linger on darker skin tones – and the two powerhouse ingredients that can finally fade them for good
You cleared the spot. You did everything right. Yet weeks, sometimes months, later, the dark mark it left behind is still there, stubbornly refusing to fade.
If this sounds familiar, you’re not alone. Post-acne marks and dark spots are among the most common skin concerns for women and men of colour and among the most misunderstood.
The skincare world has plenty to say about spots themselves, but far less about what happens after they heal.
Just this weekend, I saw a family member with a very noticeable dark mark on his face. When I asked what had happened, he told me he’d had a spot and picked it. What he was left with was far more visible and longer-lasting than the original blemish.
It was a powerful reminder of something I talk about constantly: on darker skin tones, picking a spot doesn’t just risk scarring. It triggers a pigmentation response that can take months—sometimes longer—to fade.
Why Dark Spots Linger on Darker Skin Tones
When the skin experiences inflammation from a spot, rash, scratch or other trauma, it responds by producing melanin. This is part of the skin’s natural defense mechanism. But deeper skin tones already produce more melanin, so this response can be much stronger.
The result is post-inflammatory hyperpigmentation: dark marks that remain long after the original blemish has healed.
For women over 45, the process can feel even slower because skin cell turnover naturally decreases with age. The same ingredients can still work, but they require patience and consistency.
Dark spots on deeper skin tones do not appear overnight, and they will not disappear overnight. What works is a targeted, gentle approach using the right ingredients consistently.
Tip: Never pick or squeeze spots. Every time you do, you trigger a new inflammatory response—and potentially a new dark mark. Prevention is always easier than treatment.
Vitamin C: The Brightening Powerhouse
Vitamin C is one of the most researched ingredients for fading hyperpigmentation. It works by limiting the activity of the enzyme involved in melanin production, helping to interrupt the process that creates dark spots.
At the same time, it brightens the overall skin tone, protects against environmental damage and supports collagen production.
For women and men of colour dealing with post-acne marks and uneven skin tone, vitamin C can be a genuine game-changer when used correctly.
Apply a vitamin C serum in the morning to clean skin, before your moisturiser and SPF. Start with a lower concentration of around 10% to allow your skin to adjust, particularly if you have sensitive skin.
Look for formulas that also contain vitamin E and ferulic acid. These ingredients help to stabilise vitamin C and increase its effectiveness.
Tip: Vitamin C oxidises quickly when exposed to light and air. Store it in a cool, dark place and replace it if it turns dark orange or brown. An oxidised vitamin C serum will not give you the results you are looking for.
Niacinamide: The Gentle Regulator
Niacinamide, also known as vitamin B3, works differently from vitamin C but can be equally helpful for hyperpigmentation.
Rather than limiting melanin production, it helps reduce the transfer of melanin to the surface of the skin, where dark spots become visible.
It also strengthens the skin barrier, reduces redness, minimises the appearance of pores and helps regulate oil production, making it one of skincare’s most versatile ingredients.
For women of colour with sensitive or reactive skin who find vitamin C too stimulating, niacinamide is often the better starting point.
Niacinamide can be used morning and evening and is well tolerated by most skin types. Apply it after cleansing and before heavier creams or oils. It works well with most other ingredients, including retinol, making it easy to add to an existing routine.
Tip: A concentration of around 5% is the sweet spot for most skin types. It is effective without being too irritating. Higher concentrations are available, but more is not always better.
So, Which One Should You Choose?
Both- if your skin can tolerate them.
Used together, with vitamin C in the morning and niacinamide in the morning and/or evening, they offer a strong approach to fading dark spots and creating a more even skin tone.
If you are starting from scratch, begin with niacinamide. It is gentler and more forgiving. With consistent use, you may begin to see visible improvements within four to six weeks. You can add vitamin C once your skin has adjusted.
Above all else, wear SPF every day.
As we move into autumn and the days become shorter and cooler, it can be tempting to put the SPF away. Don’t.
UV rays are present all year round. Even on overcast October days, sun exposure can darken existing marks and undo your progress.
SPF is not optional when you are treating hyperpigmentation. It is essential—every day, in every season.
The Takeaway
Post-acne marks and dark spots are not necessarily permanent, but fading them requires the right ingredients, used consistently over time.
Start with niacinamide, add vitamin C if your skin tolerates it, never skip SPF and give your skin the patience it deserves.
