Welcome to The Wellness Ledger
A weekly health led newsletter grounded in evidence-based medicine along with prospective randomized controlled trials by medical specialists. Our goal is to help you make sense of complex scientific information and turn it into clear, evidenced based practices you can use to make better decisions about your health and wellness.
Most people apply sunscreen and consider the job done.
That is not wrong. Sunscreen works. But here is something the bottle does not mention: even with SPF 50 applied correctly, UV radiation still gets through. Not enough to cause a visible burn, but enough to trigger a chain of molecular events inside your skin. This occurs quietly, every single day you spend in the sun.
Free radicals form. Collagen-breaking enzymes activate. DNA takes small hits. For years, nothing shows. Then one morning it does.
A small, rigorous field referred to as nutritional dermatology has been asking a specific question for over two decades: can eating a specific way change what happens to your skin after UV gets through? The answer, depending on the food and the study, is sometimes yes, sometimes no, and occasionally "we funded this trial ourselves so take it with a grain of salt."
TL;DR
Cooking is the mechanism, not a detail.
Cooked tomato paste with olive oil reduced measurable skin damage in a clinical trial. Raw tomatoes did not produce the same result. The preparation matters as much as the ingredient.
Green tea divided the researchers.
One trial showed catechins reached the skin and reduced UV inflammation. A larger follow-up at double the dose found zero effect. Both were well-designed studies.
"Internal SPF 1.3" is a journalist's analogy, not a measurement.
No peer-reviewed study has assigned a Sun Protection Factor to any food. Lycopene works just after photons enter, not by blocking them.
THE SCIENCE
What UV radiation actually does to your skin
Think of it in two separate stories.
UVB radiation is the shorter, more aggressive wavelength. When UVB photons hit your skin, they slam directly into DNA. The impact fuses adjacent sections of the DNA strand together. Your cells have repair machinery that finds most of these fused sections and fixes them. But sun exposure is relentless. When damage comes in faster than repair can clear it, some of those errors survive and replicate. That is how most skin cancers start.
UVA radiation is the quieter threat. It penetrates deeper, into the dermis where collagen lives, and rarely hits DNA directly. Instead it energizes molecules already in your skin, which then pass that energy to oxygen. The result is a burst of free radicals. They attack your collagen-producing cells, telling them to stop making collagen and start pumping out enzymes that break it down. Over years, that is what contributes to wrinkles and skin laxity.
Sunscreen physically stops photons from entering. Dietary antioxidants cannot do that.
They work after the photon has already penetrated, by neutralizing the free radicals it creates. That is a real and meaningful difference. It is also why no food will ever be a sunscreen replacement.
THE EVIDENCE
Five foods, ranked by the research
Each food below gets a tier rating. Tier 1: multiple independent human trials, replicated findings. Tier 2: at least one human trial, but limited or conflicting replication. Tier 3: population data only, no direct intervention trial.
DEEP DIVE
The tomato trial worth knowing
Of all five foods, tomatoes have the most credible human evidence. And the reason comes down to a chemistry detail most people skip.
In raw tomatoes, lycopene exists in a rigid crystal structure. The body absorbs very little of it. When you cook a tomato, heat breaks that structure into a more flexible form called a cis-isomer. When you add fat alongside it, bile acids in your gut dissolve the lycopene and carry it into the bloodstream. Without both steps, most of the lycopene stays in your digestive tract.
The 2011 Rizwan trial at the University of Manchester controlled for exactly this. Women ate 55 grams of tomato paste cooked in 10 grams of olive oil. Not raw tomatoes. Not lycopene capsules. The specific preparation the researchers used. And skin biopsies 24 hours after a controlled UV exposure showed significantly reduced activity of MMP-1, the enzyme that breaks down collagen, and reduced mitochondrial DNA damage.
THE "SPF 1.3" CLAIM
A co-author of this study used the comparison in a media interview to help journalists understand the modest magnitude of erythema reduction. It was never a clinical measurement. No study has applied Sun Protection Factor methodology to an oral compound. Lycopene works after photons enter the skin. SPF is a measure of photon blocking. These are different things.
THE PROTOCOL
What the trials actually used
Not prescriptions. The exact parameters from each study that showed a measurable result.
Tomatoes: cooked, with fat, daily
Tomato paste or sauce, minimum 40g. Always with olive oil or another dietary fat. Heat and fat are not optional. Raw tomatoes and lycopene capsules consistently underperform in the evidence.
Green tea: with lemon, consistently
Three to five cups daily delivers the catechin range tested in the positive trial. Vitamin C (or lemon juice) stabilizes catechins before absorption. Consistency over weeks matters more than the precise daily amount.
Pomegranate: months, not days
The Henning trial required 12 full weeks before results appeared. If the mechanism runs through gut microbiome shifts, it needs time to establish. Occasional pomegranate is not the same as consistent daily intake.
Greens and eggs: always with fat
Spinach, kale, egg yolks, bell peppers for lutein and zeaxanthin. All fat-soluble. A spinach salad with olive oil dressing absorbs meaningfully better than spinach eaten plain.
None of these studies tested whether these foods replace sunscreen. None claimed they did.
The evidence is for an additional protective layer. Wear the SPF.
READER'S PULSE
How much do you actually know about sun and skin?
Three questions. The answers might surprise you.
Q1. You apply SPF 50 correctly. What percentage of UV radiation is still getting through?
Q2. Which type of UV is most responsible for premature skin aging?
Q3. The "SPF 1.3" figure for lycopene. Where did it actually come from?
ANSWER 1 B. SPF 50 blocks roughly 98% of UVB. But UVA still penetrates regardless of SPF rating. The scale is not linear: SPF 15 blocks 93%, SPF 30 blocks 97%, SPF 50 blocks 98%.
ANSWER 2 B. UVA makes up 95% of UV radiation reaching your skin and penetrates deep enough to activate collagen-breaking enzymes. UVB causes the visible burn. UVA causes the aging you will not see for a decade.
ANSWER 3 B. A co-author of the 2011 Rizwan trial used this comparison in a media interview to help explain the modest erythema reduction observed. No dermatological protocol assigns SPF values to oral compounds.
SAVE THIS
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Sources
Rizwan M et al. Br J Dermatol. 2011. PMID: 20854436
Stahl W et al. J Nutr. 2001. PMID: 11340098
Rhodes LE et al. Br J Nutr. 2013. PMID: 23351338
Farrar MD et al. Am J Clin Nutr. 2015. PMC4548173
Farrar MD et al. (DNA damage). 2018. PMID: 29332714
Henning SM et al. Sci Reports. 2019. PMID: 31601842
Juturu V et al. Clin Cosmet Investig Dermatol. 2016. PMC5063591
Alonso A et al. Am J Clin Nutr. 2020. PMID: 32492135
Mahamat-Saleh Y et al. Am J Clin Nutr. 2019. PMID: 31380561
ATBC Study Group. N Engl J Med. 1994. PMID: 7495243
Omenn GS et al. (CARET). N Engl J Med. 1996. PMID: 8602180
This newsletter is for informational purposes only and does not constitute medical advice. Consult a board-certified dermatologist before making changes to your sun protection routine.
