You wear sunscreen every single morning without fail. You reapply before heading outdoors. You've even started avoiding the midday sun. And yet — your melasma persists, or keeps coming back just when you thought it was finally fading.
If this sounds familiar, you are not doing anything wrong. You may simply be fighting the wrong enemy.
Most sun protection — and most skincare routines — is built around blocking UV rays. But two triggers get far less attention: infrared-A radiation and heat, neither of which standard UV filters are designed to address. Melasma is multifactorial, driven by hormones, genetics, visible light and inflammation, so heat and IRA are rarely the whole story. For those already prone to it, though, they may be an overlooked piece of why pigmentation keeps returning despite diligent SPF use.
What Is Infrared Radiation, and Why Should You Care?
The sun emits energy across a broad spectrum. The part most of us are familiar with is ultraviolet radiation — UVA and UVB — which accounts for around 7% of solar energy reaching the earth's surface. Visible light accounts for another 39%. The remaining 54%? That is infrared radiation.
Infrared radiation (IR) is divided into three bands: IRA (760–1400nm), IRB (1400–3000nm), and IRC (3000nm and above). Of these, IRA penetrates deepest into the skin — and may reach the dermis and even the subcutaneous tissue below. You cannot see it. You cannot feel it the way you feel a sunburn. But it is constantly hitting your skin, and for those with melasma-prone skin, it is quietly making things worse.
Research has shown that IRA stimulates the production of reactive oxygen species (ROS) — unstable molecules that trigger oxidative stress in skin cells. This oxidative stress activates melanocytes, the cells responsible for producing melanin. The result: pigmentation that forms or worsens even when UV exposure has been carefully managed.
In other words, your SPF 50 sunscreen may be doing its job perfectly — and your melasma can still darken, because IRA and other non-UV triggers may still contribute despite diligent UV protection.
Heat: The Trigger That Is Hiding in Plain Sight
Infrared radiation is not the only heat-related aggravator. Thermal heat itself — regardless of its source — has been identified as an independent trigger for melasma flares.
This is known as heat-associated worsening of melasma, and dermatologists have observed it in patients who:
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Work in front of ovens, open flames, or industrial heat sources
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Spend extended time in hot, humid climates (highly relevant across Southeast Asia)
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Use hot showers, saunas, or steam rooms regularly
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Cook frequently over a stovetop
The mechanism is thought to involve heat-sensitive receptors in the skin that stimulate melanocyte activity. Essentially, sustained warmth — even without sunlight — can signal the skin to produce more melanin. For those who already have melasma, it does not take much to reignite a patch that had started to fade.
This explains a pattern many melasma sufferers recognise but cannot fully explain: pigmentation that worsens during hot weather or stuffy indoor conditions, even during periods with minimal sun exposure.
Why Standard Sunscreens Fall Short
A traditional sunscreen is formulated to filter or reflect UVA and UVB radiation. That is what the SPF number and PA rating measure. Nothing more.
Most formulations — even high-SPF options — offer no specific protection against IRA. This is not a flaw; it is simply not what they were designed to do. The problem is that for people with melasma, the picture of what "sun damage" actually means is much broader than the sunscreen category has historically addressed.
Understand the Invisible Skin Damage That You May Have Overlooked
If you are managing melasma and relying on sunscreen alone as your protective layer, you are working with an incomplete shield.
Related reading: 4 Things Your Sunscreen Must Have If You Are Prone to Melasma
What Protection Against IRA and Heat Actually Looks Like
Addressing infrared and heat-induced melasma requires two things: a topical product that goes beyond UV filtration, and an internal approach that addresses melanin production at its source.
On the outside: choose a sunscreen formulated for the full spectrum
Not all sunscreens protect against IRA. The ones that do typically include antioxidant ingredients that neutralise the free radicals IRA generates, alongside broad-spectrum UV filters.
Crystal Tomato® Beyond Sun Protection is formulated specifically with this broader threat in mind. Rated SPF79+ PA++++, it shields against UVA, UVB, HEV (blue light), and infrared radiation — the full range of daily aggressors that conventional sunscreens leave unaddressed. Its antioxidant-rich formula works to neutralise free radical damage from IRA, while Ectoin — a clinically recognised ingredient — helps protect skin cells from environmental stressors and soothes heat-related irritation.
For those with melasma-prone skin, this kind of multi-spectrum protection is not a premium extra. It is the baseline.
Related reading: Why Your Regular Sunscreen Can't Stop Blue Light Damage
On the inside: target melanin production where it starts
Even with the best topical protection, some UV and infrared energy still reaches the deeper layers of skin. This is where an internal approach becomes critical.
The Crystal Tomato® Whitening Supplement is formulated from non-GMO tomatoes and contains colourless carotenoids — a rare class of compounds that absorb UV wavelengths and support the skin's antioxidant defences from within.. Unlike the coloured carotenoids found in regular tomatoes, these colourless carotenoids do not cause skin yellowing and have been clinically shown to reduce melanin production from within.
Importantly, the colourless carotenoids in Crystal Tomato® Whitening Supplement do not simply mask the effects of IRA damage — they address the upstream trigger by neutralising the oxidative stress that activates melanocytes in the first place. Combined with L-cysteine, an amino acid that supports glutathione production, the supplement works to suppress the internal mechanisms that cause pigmentation to form and worsen.
In a clinical study conducted at Singapore's National Skin Centre, patients with melasma showed significant improvement after 54 days of supplementation. The supplement was also shown to deliver a 32% faster reduction in dark spots and a 50% reduction in dark spot intensity over 12 weeks.
Related reading: The Truth About Colourless Carotenoids: The Science of Oral Skincare
The Practical Reality for Melasma-Prone Skin in a Hot Climate
For those living and working in Singapore, Malaysia, and across Southeast Asia, the IRA and heat challenge is not seasonal — it is daily. The region's year-round heat and humidity mean that infrared exposure and thermal triggers are constant, not something to manage for a few summer months.
This makes a robust, multi-layered approach non-negotiable:
1. Apply broad-spectrum, IRA-aware sun protection every morning — regardless of whether you plan to go outdoors. Windows do not completely block IRA. Neither does being under shade if ambient heat is high.
2. Reapply every 2 to 3 hours if you are outdoors, perspiring, or in environments with direct heat exposure.
3. Support your skin from within. Topical protection can only do so much. The Crystal Tomato® Whitening Supplement adds an internal layer of defence that works at the melanocyte level, addressing the root cause rather than only the surface effects.
4. Minimise unnecessary heat exposure where possible — shorter hot showers, caution around steamy kitchen environments, and avoiding saunas during active melasma flares.
The Bottom Line
Melasma is a complex, chronic condition. For many people, the persistence of their pigmentation has nothing to do with inconsistent sunscreen use — it has to do with the threats that sunscreen was never built to stop.
Infrared radiation and heat are not fringe concerns. They are scientifically documented triggers that activate the same melanin-producing pathways as UV light. If your melasma management plan does not account for them, there will always be a gap.
The most effective approach combines outside-in protection that covers the full spectrum — including IRA — with an inside-out strategy that addresses melanin production at its source. For melasma-prone skin, that combination is not optional. It is the difference between managing your condition and staying one step ahead of it.
