What Causes Dark Spots & Uneven Tone — and How to Treat Them

Dark spots don't all come from the same place — and knowing which kind you're dealing with changes what actually helps. "Uneven tone" is a catch-all for a few different things happening underneath, so before reaching for a brightening product, it helps to know what's causing yours.

Sun Exposure (the most common cause)

UV exposure triggers extra melanin production as a defense response — over years, that shows up as sunspots or patches of tone that's darker than the skin around it, usually on the areas that see the most sun: cheeks, forehead, backs of hands. This is also the type most likely to keep coming back without consistent SPF, no matter what treatment you're using.

Post-Inflammatory Hyperpigmentation

Ever notice a mark left behind after a breakout, cut, or irritation finally heals? That's post-inflammatory hyperpigmentation — the skin overproduces pigment while repairing itself. It's extremely common after acne and tends to fade on its own eventually, but that can take months without help.

Hormonal Changes (Melasma)

Melasma shows up as larger, often symmetrical patches — commonly on the cheeks, forehead, or upper lip — and is linked to hormonal shifts (pregnancy, birth control, thyroid changes). It tends to be more stubborn and sun-reactive than other types, so daily SPF matters even more here.

Natural Aging

As skin cell turnover slows with age, melanin can distribute more unevenly across the surface, and years of cumulative sun exposure catch up all at once. This type tends to show up gradually rather than as a distinct spot.

What Actually Helps

Regardless of the cause, a few things matter across the board:

• Daily SPF — without it, brightening ingredients are working against new damage being added faster than they can fade the old.
• Consistency — tone-evening ingredients work gradually, with regular use over time, not overnight.
• A formula built for the job — targeted brightening ingredients at a meaningful, medical-grade strength, rather than a general moisturizer.

MudadMD's Dark Spot Corrector is physician-developed and formulated at medical-grade strength with naturally derived ingredients to target discoloration and uneven tone — fragrance-free and dermatologist tested. Curious what ingredients typically do this kind of work? Our explainer on vitamin C, retinol, and peptides breaks down what each one is actually good for.

See the full lineup for this concern: Shop for dark spots & uneven tone →