Why Summer Makes Hyperpigmentation Worse (And What Actually Works)
Every June, I have the same conversation with women in my office.
They come in frustrated. The dark spots they faded last winter are back. The melasma they thought was finally calm has flared. The post-acne marks they have been working on for months look more visible than ever.
They want to know what they did wrong. The answer is almost always nothing. Summer simply changes the rules for pigmented skin, and most people have never been told what to expect or how to treat it properly during the warmer months.
As a Nurse Practitioner who has been treating hyperpigmentation in Waterloo Region for nearly a decade, here is what you need to understand about summer hyperpigmentation, and what treatments actually work.
Why does hyperpigmentation get worse in the summer?
Summer increases hyperpigmentation through three combined factors: UV and visible light exposure, increased heat at the skin's surface, and seasonal hormonal shifts. All three stimulate melanocytes (the pigment-producing cells) to produce more pigment as a protective response.
Most people understand that the sun causes dark spots. What they do not realize is that visible light (the light you can see, not just UV) also triggers pigment production. This is why melasma can flare even when you wear sunscreen religiously and rarely go in direct sun.
Heat is the second factor. When the skin's surface temperature rises, even without UV exposure, melanocytes can become more reactive. This is why hot yoga, saunas, and even cooking over a hot stove can worsen pigmentation in sensitive skin.
Hormonal shifts are the third piece, and this is where my role as an NP becomes especially relevant. Estrogen and progesterone fluctuations both influence melanocyte activity. If you are perimenopausal, postpartum, or on hormonal contraception, your skin is more reactive to all of the above.
What are the different types of hyperpigmentation?
The three most common types we treat are melasma (hormonally-driven brown or grey patches, often symmetrical), post-inflammatory hyperpigmentation (dark marks left behind by acne or trauma), and solar lentigines (true sun spots from cumulative UV exposure). Each responds to different treatments.
This distinction matters because treating melasma like sun damage can make it dramatically worse. Aggressive laser treatments designed for surface pigment can stimulate melasma to come back darker than it was.
This is why every hyperpigmentation client at Bonita gets a proper skin assessment before we recommend treatment. We look at your skin under different light, ask about your hormonal history, and trace the pattern of your pigmentation to understand what is driving it.
What treatments actually work on hyperpigmentation?
The most effective hyperpigmentation treatments combine medical-grade topicals (like tyrosinase inhibitors and retinoids), professional treatments matched to your pigmentation type (IPL, PicoSure Pro, or chemical peels), and consistent broad-spectrum mineral SPF. No single treatment works alone.
At Bonita we tailor the protocol to the pigmentation type. Here is the general framework.
How do we treat solar lentigines (true sun spots)?
Solar lentigines respond best to IPL (Intense Pulsed Light) and PicoSure Pro laser. IPL targets the pigment with broad-spectrum light, causing the spot to darken briefly before flaking off in 7 to 14 days. PicoSure Pro uses focused energy to shatter pigment without heating the surrounding skin.
Both treatments are excellent, but timing matters. We typically do not treat solar lentigines during peak summer because UV exposure immediately after treatment can cause rebound pigmentation. For Waterloo Region clients, we plan IPL and laser treatments for late September through March.
During the summer months, we focus on prevention and maintenance with topicals and gentle in-office treatments.
How do we treat melasma?
Melasma requires a gentler, longer-term approach. We avoid aggressive heat-based treatments and focus on tyrosinase inhibitors (like tranexamic acid, kojic acid, and azelaic acid), prescription-grade topicals, gentle chemical peels, and very conservative laser if appropriate. Melasma management is ongoing, not one-and-done.
Melasma is the type of pigmentation most affected by hormones, which is why so many women experience it during pregnancy, perimenopause, or when starting hormonal contraception. Treating it well means looking at your whole hormonal picture, not just your skin.
If your dark patches appeared during pregnancy or perimenopause, and they fade in winter and return in summer, you likely have melasma. Please be careful about any clinic that wants to laser these patches aggressively. The result is often worse than the starting point.
How do we treat post-inflammatory hyperpigmentation?
Post-inflammatory hyperpigmentation (PIH) from acne or trauma fades best with consistent medical-grade skincare, gentle chemical peels, and the AlumierMD or ZO Skin Health protocols we customize at Bonita. Microneedling can also help once the inflammation has fully resolved.
PIH is one of the most rewarding things to treat because it responds so well to consistency. The combination of a tyrosinase inhibitor, a retinoid, and a series of peels can dramatically improve PIH in 3 to 6 months.
What should I be doing every single day this summer?
Three non-negotiables for anyone with pigmented skin in the summer: a broad-spectrum mineral SPF 30+ applied every morning and reapplied midday, an antioxidant serum (like vitamin C) under your sunscreen, and a tyrosinase inhibitor if you have active hyperpigmentation.
Mineral sunscreen (zinc oxide, titanium dioxide) protects against visible light as well as UV, which chemical sunscreens do not. This matters for melasma especially.
Reapplication is the part most people skip. SPF needs to be reapplied every 2 hours of direct exposure, and any time you sweat heavily or wipe your face.
If you are not sure what to use, we carry medical-grade SPF at Bonita and can match you to the right one for your skin type during your consultation.
When is the right time to start treatment?
If you have active hyperpigmentation, start now with the topical and skincare side of the protocol. We typically schedule in-office laser and IPL treatments from September through March, when UV exposure is lower and the risk of post-treatment rebound pigmentation is minimized.
Starting your topical regimen in June means your skin will be primed and ready when fall treatment season arrives, and you will see better, faster results when we begin in-office work.
Book your skin consultation at Bonita
Hyperpigmentation is one of the most rewarding things we treat at Bonita, but it requires the right approach for your specific type. If your dark spots are bothering you and you want a proper assessment and a plan that actually works, we would love to see you.
Book a skin consultation at bonitamedicalaesthetics.janeapp.com, or call or text us at 519-404-3444. We will look at your skin properly, walk you through what we are seeing, and build you a plan that respects both your skin and the season.
