You just spent the Fourth on a patio, a lake, a rooftop, a beach towel — SPF reapplied every two hours like a good patient. Good. Keep doing that.
But here’s what you need to know about sunscreen: sunscreen is a shield, not a repair crew. It blocks radiation from hitting your skin. It does nothing for the UV that already got through — and by July, plenty already has. The damage that turns into fine lines, sunspots, and eventually something worse isn’t happening on your skin’s surface. It’s happening inside the cell, in the DNA.
Even with optimal sunscreen application, you still want to protect your skins regenerative power this summer.
Skin Cancer Chemoprevention: Nicotinamide (Vitamin B3)
Every time UV hits your skin, it burns through your cells’ NAD+ — the fuel your DNA repair machinery runs on. Less NAD+ means less repair. Less repair means the damage from today’s sun doesn’t just fade — it stacks.
A landmark clinical trial put 500 mg twice a day of Vitamin B3 up against placebo in people with a history of skin cancer, and it cut new nonmelanoma skin cancers by 23% and precancerous lesions by up to 20%, in twelve months. A follow-up study tracking over 33,000 people found the same pattern at scale — and the protection got even stronger, up to 54%, in people who started it after their first skin cancer diagnosis.
A large retrospective study of over 33,000 veterans confirmed a 14% overall reduction in skin cancer risk, with up to a 54% reduction when nicotinamide was started after the first skin cancer. Nicotinamide works by replenishing cellular NAD+ (depleted by UV radiation), enhancing DNA repair, and protecting against UV-induced immunosuppression.
The catch: this only works if you keep taking it. The protection doesn’t carry over once you stop, which tells you exactly what this is — not a one-time fix, but daily maintenance for the repair system you’re relying on every time you’re outside.
My Personal Favorite: Astaxanthin
Astaxanthin is a xanthophyll carotenoid – the pigment that gives salmon, shrimp, krill, and marine algae their color. It has a unique radial absorbing capacity that is 100-500 times higher than a-tocopherol, and 10 times greater free radical scavenger than b-carotene, lutein, and lycopene.
Plus, it’s unique molecular shape lets it span the cell membrane to neutralize reactive oxygen specis inside and outside the cell.
In the studies, that translates to real, measurable data: less redness after sun exposure, better-preserved moisture, and — over a 16 week period a measurable slowdown in the wrinkle and moisture-loss progression that untreated skin showed over the same period.
Clinical Pearl: My fair haired and light skinned patients living in our high CO altitude notice a difference with Astaxanthin. If you take it at bedtime, it can also improve the quality of your sleep.
What This Actually Looks Like This Week
While my patients tend to see faster results to their skin, most of the research on oral skin protection — astaxanthin included — needed at least 10 weeks of consistent use before results showed up. That’s basically the rest of your summer, starting now, which makes today a genuinely good day to start.
Nicotinamide and astaxanthin aren’t replacements for SPF, they’re what’s covering you after some UV inevitably gets past it to reduce the long term damage to the skin.
Join My Summer Movement Challenge
This is the same principle behind everything I build for my clients: the systems that hold up under real-life conditions beat the ones that only work when life is convenient.
Summer is exactly when that gets tested — the routine you had in March doesn’t survive vacations, backyard cookouts, and 9pm sunsets, and most people don’t lose their progress because they stopped caring. That’s what the Rise to Peak Summer Challenge is for — a free daily movement challenge that you can join to track 30 min of movement a day to help you maintain the health progress you made over the rest of year.
Join the Summer Movement Challenge here