Here is a solid video from Dr. Brad Stanfield regarding increasing rates of skin cancer (melanoma) in many places around the world.
There are many reasons for this including the fact that most countries have aging-populations, suncreen use encourages more “risky” sun exposure behavior, tanning bed use, etc.
There are also many unique gender differences between women/men and the age of diagnosis. It is clear that sun exposure results in skin aging, but I’m also not sure that sun avoidance is the best strategy either.
I wish there was something that touched on diet and melonoma risk included. Diets these days tend to be pretty poor and I suspect that is at least a factor in this equation.
I cringe at the amount of sun exposure I had when young…
What does everyone’s sun exposure philosophy here look like?
Amen, brother!!! Oh, the foil tanning mats and the baby oil!!! I’m so jealous of today’s kids who will never do that to themselves!!!
For vanity reasons alone, I expose very little skin and I don’t leave the house without spf 50. Until about 3 years ago, I was doing the same but only using spf 30.
My friends who golf have commented on their cancers they’ve had removed from their non gloved hands, so I very recently started keeping an spf stick in my car to apply to the back of my hands on particularly long drives.
I mostly don’t use spf on my hands because I mess with my hair too much and then any lotion will make my hair look greasy
It’s because sun exposure is good for you. (Vitamin D). 15 minutes of sun exposure at noon in the summer will give you what you need. I try to stay out for 15 minutes at a time and then cover up with clothing. Many people including, my husband got skin cancer (melanoma) in places that were never exposed to sunlight.
You can just take a supplement. My Vitamin D levels are normal.
15 minutes at noon in the summer isn’t insignificant in terms of damage to the skin over a long time.
Most of the chemical sunscreens prevent sunburn but do little to prevent cancer. In a 20-year study in Australia of a group of “beach-bums” that religiously used chemical sunscreens, they had the same skin cancer rate as the control group.
That should not come as a surprise since chemical sunscreens don’t actually block UV rays, they just block the chemicals produced by UV rays that result in sun burn. The DNA damage cannot be prevented by chemicals. Only UV ray blockers (mineral sunscreens based on Zinc Oxide or Titanium dioxide) that reflect UV rays can prevent DNA damage.
Here are 2 simple experiments to check if your sunscreen actually blocks UV rays:
Wrap plastic sheet (Saran Wrap) around part of your arm and apply the sunscreen over the plastic sheet as well as an exposed part of the arm (control) and then expose your arm to 4 hours of sunlight. With chemical sunscreen, only the exposed part of the arm will be protected from sunburn. With mineral sunscreens, both parts of the arm will be protected from sunburn.
Expose your arm to 2 hours of bright sun (without applying any sunscreen). Then apply chemical sunscreen to half the area on your arm (and avoid further exposure to sun). By the same evening (or next morning) you can see significantly less sunburn or tanning in the area you applied the chemical sunscreen, showing that chemical sunscreens work by neutralizing chemicals produced by the UV light (not by blocking the UV light). Of course any DNA damage from UV light, cannot be neutralized by chemicals. Conversely, if you repeat this experiment with mineral sunscreens, you will see no effect of the sunscreen after sun exposure.
I pack both kinds of sunscreen when I go to a beach : I use the mineral sunscreen before sun exposure, but then apply the chemical sunscreen after sun exposure to keep sunburn under control for any areas I missed (or where the mineral sunscreen got washed away and I forgot to re-apply in time). Basically chemical sunscreens are the best after exposure protection, even if the protection only prevents the painful symptoms (skin peeling), not skin cancer.
I don’t think this is true because the MoA of chemical and mineral sunscreens are the same nowadays, UV light absorption:
It is important for dermatologists to recognize that the primary MOA of modern physical sunscreen agents is the very same protective mechanism of chemical sunscreens: absorption of UV light.2-5 In fact, it was recently found that modern particulate-sized physical zinc oxide and titanium oxide reflected <5% of incoming UV light on average.6 Rather than relying on reflection and scatter, the overwhelming majority of the attributable protective effect of zinc oxide and titanium dioxide is by UV light absorption, which excites electrons from the valence band to the higher energy conductance band. This energy is later primarily dissipated as heat in a manner analogous to chemical sunscreen UV light absorption.1, 7
According to Avi Bitterman lentigo maligna melanomas is more impacted by chronic sun exposure rather than intermittent burning (which would primarily cause nodular melanomas).
Thanks for clarifying that nano-particulate formulations of zinc oxide and titanium dioxide (that are preferred by users since they don’t look like your skin is covered with white paint) work primarily by absorbing UV rays (and radiating heat) rather than reflecting UV rays. That still means that mineral sunscreens involve no chemicals that are absorbed by the skin (or into the blood stream) and no chemicals by-products of interaction with UV rays.
It looks like I was also mistaken regarding the effectiveness of chemical sunscreens for cancer prevention 2018 Australian study of effectiveness of chemical sunscreens. The linked study says “Meta-analyses of observational studies, most conducted more than 15 years ago, have shown null or positive associations of sunscreen use with melanoma risk”, which is what I had based my claim on. However, it is now believed that the negative results are due to poor study design (lack of proper case-controls). Newer case-control studies show a 40-50% melanoma reduction in an Australian study and a 33% reduction in a Norwegian study.
In addition, the best chemical UV filters for sunscreens (Tinosorb, Mexoryl or Uvinul) are not approved by the FDA and hence the most effective chemical sunscreens are not available in USA Standford guidance on sunscreens. Furthermore all chemical sunscreens lose effectiveness, typically after 1-2 hours, even without exposure to water, since the chemicals are gradually absorbed into the bloodstream. Many users are not aware that chemical sunscreens need to be re-applied every 1-2 hours, while mineral based sunscreens only need to be re-applied if washed away by water (or heavy sweating). Hence effectiveness of chemical sunscreens in studies where subjects have sunscreen application monitored by the researchers show effectiveness, where self-reported usage may not show effectiveness.
Even modern physical sunscreens are sometimes known to leave patients with a cosmetically unacceptable ‘white cast’, as both zinc oxide and titanium dioxide reflect visible light.
Here’s a randomized trial with chemical sunscreen that showed a causal reduction in melanoma:
Ten years after trial cessation, 11 new primary melanomas had been identified in the daily sunscreen group, and 22 had been identified in the discretionary group, which represented a reduction of the observed rate in those randomly assigned to daily sunscreen use (hazard ratio [HR], 0.50; 95% CI, 0.24 to 1.02; P = .051). The reduction in invasive melanomas was substantial (n = 3 in active v 11 in control group; HR, 0.27; 95% CI, 0.08 to 0.97) compared with that for preinvasive melanomas (HR, 0.73; 95% CI, 0.29 to 1.81).
“that are preferred by users since they don’t look like your skin is covered with white paint”
I meant users of mineral/physical sunscreens prefer the newer nano-particulate formulations, even though they still result in ‘white cast’, whereas the older zinc oxide formulations seem to apply white paint to the face.
I’m definitely no expert, but I happen to love mineral spf and used it most of my life, however, I now make an effort to use chemical because I learned from Lab Muffin that chemical does a better job with one of the rays (sorry, I can’t remember offhand, but I could try to search if interested) .
FYI, I am in the US and get Korean SPF shipped in because my eyes don’t tolerate US spf.
