Did you know that your skin works overtime every single day? I was at a recent medical education event, a speaker said something that stopped the entire room cold: "The skin is a chronic wound." It is a striking way to put it. But the science backs it up completely. Your skin is the body's largest and most exposed organ—and unlike any internal organ, it faces an unrelenting, daily assault from the outside world. UV radiation. Air pollution. Particulate matter. The chemicals in products we apply to our bodies. Processed foods. Hormonal decline. Even psychological stress leaves a mark on the skin at a cellular level. Every single day, your skin absorbs the damage, mounts a response, and attempts to repair itself—over and over, without a break.
Think about that. The skin never clocks out. No other organ in your body is asked to do that.
So, this July—UV Safety and Skin Cancer Awareness Month—I want to do more than remind you to wear sunscreen. I want to talk about what your skin is actually up against, why protecting it goes well beyond blocking a sunburn, and what we can do together at TREVI to give this remarkable organ the support it deserves.
What Your Skin Faces Every Single Day
Ultraviolet Radiation
UVB rays burn the surface. UVA rays penetrate deeper—reaching into the dermis—where they damage DNA, degrade collagen and elastin, and trigger chronic low-grade inflammation. UVA passes through window glass. It does not require a sunny sky. It is present even in overcast conditions. It accumulates silently over decades and does not give you the warning of a sunburn. This is the radiation that drives premature aging, pigmentation changes, and the long-term structural breakdown of skin that we see every day in the office.
Environmental Pollution
Research published in PubMed Central[1] demonstrated that combining UV exposure with ozone and diesel exhaust emissions produces an additive inflammatory effect on the skin—amplifying oxidative damage markers and disrupting barrier proteins like filaggrin and involucrin far beyond what UV alone causes. When the skin barrier breaks down, inflammation rises, and the healing response—that chronic wound cycle—ramps up again. For patients living in or near any metropolitan area, this is not a theoretical risk.
Hormonal Decline
Estrogen, testosterone, DHEA, and growth hormone all play active roles in maintaining skin structure, collagen synthesis, hydration, and the capacity for wound repair. As these hormones decline with age—or drop precipitously at menopause—the skin loses critical biological support. Wound healing slows. Collagen production falls. The skin becomes thinner, drier, and more fragile. This is one reason hormone optimization is not purely about energy and libido. It directly affects the health and resilience of your skin.
What We Eat and What We Ingest
Highly processed foods drive systemic inflammation—and that inflammation shows up on the skin. Advanced glycation end-products from high-sugar diets literally cross-link collagen fibers, making the skin stiffer and more prone to wrinkling. Alcohol disrupts sleep and increases oxidative stress. Nutrient deficiencies in vitamin C, zinc, omega-3 fatty acids, and protein compromise the very building blocks the skin needs to repair itself. And the chemicals we absorb through products—sunscreens, lotions, plastics—are a growing area of concern that I will come back to shortly.
The Net Result
Layer all of this on top of each other, day after day, year after year, and what you have is a skin barrier under chronic siege. Constantly attempting repair. Chronically inflamed at a low level. Gradually losing ground to cumulative damage. Which is exactly why what we do to support the skin at TREVI is not cosmetic in any dismissive sense. It is a legitimate part of preventive medicine.
You Need the Sun. Here's How to Be Intelligent About It.
I am not here to tell you to avoid sunlight. That would be both impractical and medically inaccurate. Sunlight—specifically UVB radiation—is the primary trigger for vitamin D synthesis in the skin, and vitamin D is not optional. It is essential for bone density, immune regulation, mood stability, metabolic health, cardiovascular function, and cancer prevention.
Research from the Linus Pauling Institute[2] and peer-reviewed data from PubMed[3] confirm that sensible sun exposure—exposing the arms and legs to midday sun between 10 am and 3 pm for approximately 10 to 20 minutes, two to three times per week—is sufficient to maintain healthy vitamin D levels for most fair-skinned adults. The critical nuance is this: vitamin D synthesis reaches a plateau quickly. Once your skin has produced the vitamin D it needs from a brief exposure, additional time in the sun without protection does not produce more vitamin D. It only produces more damage.
The smart strategy is intentional, brief, unprotected exposure—and then protection for any extended time outdoors.
A practical note for anyone living in the Chicago area: at latitude 42° North, meaningful UVB for vitamin D synthesis is only reliably available from approximately April through September. During the remaining months, no amount of outdoor time will produce adequate vitamin D through the skin. Supplementation during that period is not a preference—it is a clinical necessity. We monitor your levels and adjust accordingly.
The Technology That Has Already Stood the Test of Time
There is always something new in aesthetics. Every month brings a new device, a new wavelength, a new acronym with a bold claim. And while innovation matters—and we follow everything closely—I want to spend a moment on a technology that has not needed to chase trends, because the science has already validated it thoroughly: BroadBand Light.
BBL is not a newcomer. It has been in clinical use for more than two decades. Its longevity in the field is not an accident. It is the result of something most aesthetic technologies cannot yet claim: a peer-reviewed published evidence base that has grown stronger over time.
What the Research Actually Shows
A landmark study published in the Journal of Investigative Dermatology[4] demonstrated something that changed how I think about this technology: regular BBL treatments do not merely improve how skin looks. They change how skin behaves at a molecular level.
- BBL activates over 1,000 genes associated with youthful skin function
- It downregulates genes associated with aging and chronic inflammation
- Treated skin shows a gene expression profile more closely resembling younger skin—even years after consistent treatment
- Collagen and elastin production is stimulated, improving both texture and structural integrity
- Pigmentation, vascular irregularities, and sun damage are addressed at the source, not masked
This is the distinction between a treatment that temporarily improves appearance and one that reprograms the skin's underlying biology. BBL is the latter.
When patients ask about the "latest" device, I always answer the same way: the question is not whether something is new. It is whether it works, whether it is safe, and whether the results hold up over time. BBL checks all three, with a depth of evidence that newcomers have not yet earned.
BBL Is Not Only for Your Face
This is one of the most consistently underused aspects of what BBL can do—and one I hear from patients who have been coming in for facial treatments for years without realizing the same benefits are available everywhere the sun has touched them.
The skin on your face gets the attention. But sun damage, pigmentation, vascular irregularities, and accelerated aging do not limit themselves to the face. They follow the sun—and for most people, that means the neck, chest, décolletage, arms, hands, and legs have accumulated years of damage without any intervention.
A note worth making: the hands and the neck give away chronological age faster than the face does in many patients, precisely because those areas are most often skipped. If you have been investing in your facial skin, extending that investment south is a logical and meaningful next step. The biology works exactly the same way.
Why We Recommend Mineral Sunscreen—and Why It Matters
Not all sunscreens are created equal. This is not a marketing position. It is chemistry, and the distinction matters enough that I want to explain it clearly.
There are two categories of sunscreen active ingredients: chemical (organic) filters and mineral (physical) filters. Most mass-market sunscreens use chemical filters—oxybenzone, avobenzone, octinoxate, octocrylene, homosalate—because they are lightweight, clear, and cosmetically comfortable. For years, they were considered unremarkable from a safety standpoint. That has changed.
The Systemic Absorption Question
A series of studies conducted by FDA researchers and published in JAMA[5] found that common chemical sunscreen ingredients enter the bloodstream within a single day of use, at concentrations that dramatically exceed the FDA's safety threshold of 0.5 ng/mL. Oxybenzone, in particular, reached plasma concentrations as high as 258 ng/mL—more than 500 times above that threshold. These ingredients have been detected in breast milk, amniotic fluid, urine, and blood.
To be clear about what the evidence does and does not say: FDA researchers themselves stopped short of declaring chemical sunscreens harmful. Their conclusion was that the known risk of sun exposure still outweighs the risk of chemical filter use, and that more safety data is urgently needed. That is not an exoneration—it is an acknowledgment that we do not yet fully understand the long-term implications of daily systemic absorption of these compounds, particularly in children, pregnant women, and patients with hormone-sensitive conditions.
That is the precautionary principle, and it is why we at TREVI recommend mineral protection.
Why Mineral Sunscreen Makes Clinical Sense for Our Patients
- Zinc oxide and titanium dioxide—the two active ingredients in mineral sunscreens—are the only sunscreen actives the FDA currently classifies as both safe and effective[6]
- Mineral sunscreens work at the surface of the skin, creating a physical layer that reflects and scatters UV without requiring systemic absorption
- They are immediately effective upon application—no 20 to 30 minute waiting period required
- They are well tolerated by sensitive skin, rosacea, melasma, and post-procedure skin—all relevant for our patient population
- For patients on hormone therapy, minimizing unnecessary endocrine-disrupting exposures is a reasonable and consistent clinical principle
- Mineral SPF is specifically appropriate for post-BBL skin, which is temporarily sensitized and benefits from the gentlest barrier available
I want to be direct: any broad-spectrum SPF 30 or higher is better than unprotected skin. But when you have the option to choose—and at TREVI, we make sure you do—mineral protection is our clinical recommendation.
A Final Thought
Your skin has been working for you every single day of your life. It has been healing quietly, defending you against damage you never even see, and doing so without a single day off. This July, I invite you to think about what you can give it in return—not out of vanity, but out of genuine respect for the biology you are living in.
We are here to help you do that thoughtfully, with honest guidance and the best available science.
Dr. Josie
References
- Nakagawa NK et al. Additive effect of combined pollutants to UV-induced skin OxInflammation damage. PMC. ncbi.nlm.nih.gov
- Holick MF. Vitamin D and Skin Health. Linus Pauling Institute. lpi.oregonstate.edu
- Kramer MS et al. Estimation of exposure durations for vitamin D production without sunburn risk. PubMed. pubmed.ncbi.nlm.nih.gov
- Chang ALS et al. Rejuvenation of gene expression pattern of aged human skin by broadband light treatment. Journal of Investigative Dermatology, 2013. pmc.ncbi.nlm.nih.gov
- Matta MK et al. Effect of sunscreen application under maximal use conditions on plasma concentration of sunscreen active ingredients. JAMA, 2019–2020. rdw.rowan.edu
- FDA. Sunscreen Drug Products for Over-the-Counter Human Use. fda.gov
