
Is Sunscreen the New Margarine? - cribbles
https://www.outsideonline.com/2380751/sunscreen-sun-exposure-skin-cancer-science
======
alexandercrohde
Summary:

1\. Research shows the most popular vitamin supplements aren't useful. This
turns out to include D supplements.

2\. This is strange because "People with low levels of vitamin D in their
blood have significantly higher rates of virtually every disease and disorder
you can think of"

3\. One theory to explain this is that Vitamin D was acting as simply a marker
for sun-exposure. This is put forth by Richard Weller.

4\. To add evidence, Weller found that exposing people to sunlight for 30
minutes reduced blood pressure and increased nitric oxide levels.

5\. Article dispells concerns about sun exposure by pointing that the type of
skin cancer one is likely to get from the sun is actually very safe
(carcinomas) as compared to melanoma (1-3% of cases).

6\. Cites a study 30,000 Swedish sunbathing women and found greater health and
decreased odds of dying from a melanoma.

7\. Observes the counter-intuitive nature of sun-exposure being harmful to a
species that evolved outdoors.

8\. Questions the validity of SPF recommendations when they don't factor in
race / skin-tone.

9\. Observes an example of "common knowledge" being wrong with margarine which
was wrongly perceived to be healthier than butter for a long time. Suggests
the very thing may be happening here.

~~~
hyperpape
As a general principle, 7 does not seem valid (consider the case of sugar
consumption). Life expectancy has increased and causes of death have changed.
Cancer is now a much greater issue, while diseases of malnutrition are rare in
the developed world.

Given that melanoma is so rare, it might be valid in this particular case, but
it absolutely makes sense that sun exposure could have a mixture of
positive/negative effects in prehistoric times, but a different mix today.

Another factor that's relevant to some of us: as someone of Northern European
descent living in the southern US, I'm not in the environment that selected
for my pale skin (and my ancestors didn't wear t-shirts in February). This
effect might go in the opposite direction for dark-skinned folks living in
Northern Europe.

~~~
jstanley
> 7 does not seem valid (consider the case of sugar consumption)

How much refined sugar do you think people were eating in the environment of
evolutionary adaptation?

(Although, I agree that causes of death change as life expectancy changes, and
things that didn't matter before start to matter now that the low-hanging
fruit has been picked)

~~~
capitalsigma
The issue is that people nowadays may live in a place with a lot more UV than
their ancestors adapted to -- consider an Irish family that moved to Arizona,
for example. The same principle of "more available than evolution prepared you
for" seems also to apply.

~~~
WillPostForFood
And vice versa - consider migration from Central America to Chicago or North
Africa to Stockholm.

------
pgcudahy
This article is based on the work of Richard Weller who is trying to monetize
them at Relaxsol[relaxsol.com]. I didn't find any disclosure of this in the
article.

The mainstream view is in a paragraph buried deep: "“I don’t argue with their
data,” says David Fisher, chair of the dermatology department at Massachusetts
General Hospital. “But I do disagree with the implications.” The risks of skin
cancer, he believes, far outweigh the benefits of sun exposure. “Somebody
might take these conclusions to mean that the skin-cancer risk is worth it to
lower all-cause mortality or to get a benefit in blood pressure,” he says. “I
strongly disagree with that." It is not worth it, he says, unless all other
options for lowering blood pressure are exhausted. Instead he recommends
vitamin D pills and hypertension drugs as safer approaches."

~~~
fiter
The mainstream view amongst whom and where?

There are quotes from organizations that advocate sun exposure which are not
linked to Weller:

Cancer Council Australia’s official-position paper (endorsed by the
Australasian College of Dermatologists) states, “Ultraviolet radiation from
the sun has both beneficial and harmful effects on human health.... A balance
is required between excessive sun exposure which increases the risk of skin
cancer and enough sun exposure to maintain adequate vitamin D levels.... It
should be noted that the benefits of sun exposure may extend beyond the
production of vitamin D. Other possible beneficial effects of sun exposure…
include reduction in blood pressure, suppression of autoimmune disease, and
improvements in mood.”

Australia’s official advice? When the UV index is below 3 (which is true for
most of the continental U.S. in the winter), “Sun protection is not
recommended unless near snow or other reflective surfaces. To support vitamin
D production, spend some time outdoors in the middle of the day with some skin
uncovered.”

New Zealand signed on to similar recommendations, and the British Association
of Dermatologists went even further in a statement, directly contradicting the
position of its American counterpart: “Enjoying the sun safely, while taking
care not to burn, can help to provide the benefits of vitamin D without unduly
raising the risk of skin cancer.”

~~~
scoggs
Is it strange that I get some level of measurable joy out of reading something
official that contains a rational and balanced take on a subject such as:

"... A balance is required between excessive sun exposure which increases the
risk of skin cancer and enough sun exposure to maintain adequate vitamin D
levels..." ?

I'm not used to seeing articles / stories / write-ups / or even paragraphs
that seem to contain acknowledgement of both sides (or all sides, depending)
of a situation. Everything seems like an advertisement or a paid / sponsored
article these days so it's almost like a balanced write-up / an author
projecting a rational and honest viewpoint is this rare and refreshing change-
of-pace for me? Maybe it's not that weird but I've never really taken the time
to consider it so I've definitely never asked any friends, family, or co-
workers about it. Any thoughts?

~~~
gerbilly
> Is it strange that I get some level of measurable joy out of reading
> something official that contains a rational and balanced take on a subject

I got joy reading the article because it basically tells you _not to worry_
about moderate sun exposure.

How many articles tell you not to worry? Now that's a really rare animal in
the news media.

------
rsync
I wonder about the effects of breathing sunscreen.

In affluent, white, suburban United States it is very common to see the
religious application of sunblock to children in the specific form of aerosol
spray delivery.

Every day at the park stand still for a big cloud of aerosolized sunblock all
over your face and arms, etc.

Speaking more generally, my wife and I often discuss this or that _terrible_
practice of health or habit or child-rearing from our own parents' generation
and I am always inclined to extrapolate forward: "what are _we doing right
now_ that our kids are going to look back on with horror and amazement?" For a
long time the sunblock regime has been near the top of the list ...

~~~
ryall
Had a long conversation with a skin cancer specialist about the harmful
effects of sunscreen.

While he agreed that there can be some nasty chemicals found in sunscreen he
ended the discussion with the parting words "At the end of the day it's the
people that _don't_ use sunscreen that we see here in the clinic, not the
people that do"

~~~
pomber
Is it a skin cancer clinic? Maybe the people that _do_ use sunscreen go to
another clinic (where they don't ask about sunscreen usage)

------
brandonmenc
> How did we get through the Neolithic Era without sunscreen? Actually,
> perfectly well.

It's modern times. We optimize for long individual lives, not propagation of
the species. As lifespans increase, so should efforts to avoid cumulative,
damaging radiation.

Similarly, heavy meat consumption gave early humans an advantage, but you
shouldn't adopt that caveman behavior for a 100-year lifespan - it doesn't
"work" at that scale.

~~~
darkpuma
Most of the average lifespan increases we've seen have come from reduced
infant and childbirth mortality, not from making the elderly live to be even
more elderly. There has certainly been some of that, but it's far less
significant than the infant and childbirth mortality improvements.

> _Rowbotham and Clayton (JRSM 2008;101:454–62) make a very important point
> when they draw attention to the life expectancy at birth compared to life
> expectancy at 5+ years of age.1 They state ‘… life expectancy in the mid-
> Victorian period was not markedly different from what it is today. Once
> infant mortality is stripped out, life expectancy at 5 years was 75 for men
> and 73 for women.’ In 1995 Griffin2 produced a comparison of life expectancy
> of mature men (15+years of age) at different points in history over the last
> 3000 years_

> _The change in life expectancy of mature men^ has not changed as
> dramatically over 3000 years as might be expected, although this data must
> of necessity refer to privileged members of society._

[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2625386/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2625386/)

Note also that being economically or socially privileged would have given
these men better access to nutrition, however it would have also given them
better access to contemporary 'medicine' which may very well have been more
hazardous to their health than no medical intervention at all. How many
wealthy people in the past were poisoned by their well-meaning doctors? I'd
wager more than were saved.

^ (The numbers for women are very different, because women used to frequently
die during childbirth, but this is comparatively rare today.)

~~~
brandonmenc
> Most of the average lifespan increases we've seen have come from reduced
> infant and childbirth mortality, not from making the elderly live to be even
> more elderly.

You're missing my point.

Lifespans are increasing. The reason why is irrelevant.

Regardless, the result is that you have more time to accumulate irreversible
damage than your ancestors did, so their habits re: the sources of that damage
are not necessarily prescriptive.

There's probably a hard limit on radiation exposure, and that means you'll
have to spread it out more than your ancestors did to enjoy the same risk of
cancer - ex: same number of hours in the sun but over a longer lifespan =
shorter individual trips under the sun, but (inevitably) more of them.

~~~
darkpuma
You've missed my point, the increases in human lifespans have come from
greater success at reproduction (surviving childbirth, and surviving being a
child long enough to reach sexual maturity), which is rather contrary to what
you've suggested.

Furthermore:

> _" As lifespans increase, so should efforts to avoid cumulative, damaging
> radiation."_

The elderly are not living _much_ longer than they ever did before, so this is
basically nonsense. It makes sense if you assume that 200 years ago men were
dropping dead in their 40s like those naive life expectancy statistics would
lead to to believe, but that's not what was going on. The life expectancy of a
mature male has barely changed at all in the past few thousand years, so the
relative importance of avoiding cumulative damage like radiation has not
increased either.

~~~
brandonmenc
> naive life expectancy statistics

Yes, we all know about that. You're getting too hung up on me saying
"lifespans increase." Forget that I said that. Imagine I instead said, "we are
optimizing for health in old age more than the ancients did."

> the relative importance of avoiding cumulative damage like radiation has not
> increased either

It wasn't important at all back then because they didn't know about it.

Do you want to die in agony in your 70s from metastasized skin cancer, or
peacefully in your sleep at 80?

My point is that propagation of the species, old age, and rampant melanoma can
all exist simultaneously - so what people did in the past re: sun exposure
isn't necessarily good advice for us today.

------
paulsutter
Interesting news almost completely buried in overpolarized nonsense: sunlight
is beneficial beyond vitamin D.

Of course, sun burns are still bad for you, and excessive tanning will make
you look old at a young age. So yes do use sunscreen in moderation but don’t
avoid the sun.

~~~
zeroname
> sunlight is beneficial beyond vitamin D.

Is it though? Do we actually have the data that says so, or do we have data
that has tons of other factors mixed in, where sunlight exposure _happens to
be correlated_ with better health?

> So yes do use sunscreen in moderation but don’t avoid the sun.

Using sunscreen (according to the article) is equivalent to avoiding the sun,
as it blocks production of Vitamin D.

~~~
PKop
> Is it though? Do we actually have the data that says so, or do we have data
> that has tons of other factors mixed in, where sunlight exposure happens to
> be correlated with better health?

What other kind of data would you need, or expect to see?

Shouldn't the onus be on people claiming that, given the reality of human
evolution and existence, blocking sun exposure is the way to go?

The article points out risks mitigated by sun exposure (and their
corresponding mortality rates), and the main negative (Melanoma) and its lower
incidence. On net I think the "minimize sun exposure" advocates have a weaker
argument.

As article points out this is eerily similar to low-fat, cholesterol fear
mongering from decades ago. Funny a similar recommendation (blood pressure
pills) is given by doctors here.

~~~
Gimpei
What I'd hope to see is randomized studies or studies that exploit some random
variation for identification. The studies mentioned in the article all appear
to rely on regressions controlling for observables. But of course there could
be plenty of unobservable factors that are driving the result: the type of
people that spend a lot of time in the sun are healthier for other reasons. I
haven't read Weller's work though so maybe he has some RCTs too or maybe
someone else does.

------
msamwald
The article they cite claims that people who were less exposed to sun had
higher disease risk [1]. As far as I saw, the cited article does not include
sunscreen use in the analysis. So it might very well be that sun exposure
while wearing sunscreen might have the same benefit, minus the increased skin
cancer risk and accelerated skin aging.

EDIT: Besides that, there is very likely a huge confounding effect that was
probably not properly corrected for. The persons in the "high sun exposure"
group were much healthier than in the "avoiding sun exposure" group right from
the start (Table 1)!

[1]
[https://onlinelibrary.wiley.com/doi/full/10.1111/joim.12496](https://onlinelibrary.wiley.com/doi/full/10.1111/joim.12496)

------
DenisM
It's remarkable how much attention is given to the quantity of the desirable
Sun exposure, and how little thought is spent on the _quality_ of the light.

Absent sunscreen the UV-heavy mid-day Sun in the tropics gives me a sunburn in
15 minutes, while a morning exposure at the same locale remains perfectly safe
for all the three hours that the morning lasts. The turning point is when the
Sun crosses 45% boundary (when a match stuck in the sand becomes taller than
its shadow), so my schedule is beach-time 6-9am and 3-6pm, while the rest of
the time is spent sleeping, eating, working, and sightseeing.

I wish I could sell you some dietary supplement with this fantastic advice,
but none is needed. Well, maybe a branded box of matches is in order?..

~~~
drited
Interesting stuff. What country is this? What skin complexion?

~~~
DenisM
Typical caucasian skin - not pale, not dark. The places were Hawaii and Costa
Rica, but it should work the same anywhere in the tropics - just make use of
the match-sand trick to adjust for the local timezone.

------
jonstewart
There are obviously some biological processes that depend on sunlight, but it
also seems likely that sun exposure is a signal for “is active outside.”

~~~
adrianmonk
Or even more broadly, is active in general terms, not necessarily just
outdoors and not necessarily just physically.

I think it's likely that being active is positively correlated with good
health. probably for two reasons. One is it is probably good for you to keep
active. Too, if you have health issues, you probably are more likely to just
stick around the house and not do as much.

------
manmal
Long-term (3+ years) supplementation of vitamin D significantly decreases all-
cause mortality [1]. So yeah, take the supps if you don't get enough sunlight.
But personally I am convinced that sunlight exposure, and additional near-
infrared "supplementation" are preferable. Nitric oxide release is a double
whammy because it reduces stress within cells, and promotes endothelial health
(as mentioned in the article).

1:
[https://www.ncbi.nlm.nih.gov/pubmed/24349197](https://www.ncbi.nlm.nih.gov/pubmed/24349197)

~~~
reinhardt1053
Recent long study results (5.3 years follow up) show no benefit on vitamin D
supplement:
[https://www.nejm.org/doi/full/10.1056/NEJMoa1811403](https://www.nejm.org/doi/full/10.1056/NEJMoa1811403)

~~~
solinent
Only 2000IU per day. I'd like to see one with 10000IU.

------
nabla9
Rebuking one point in the article.

This article confuses treating vitamin D deficiency to taking high doses of
vitamin D.

1) Studies show that excess amount of vitamin D provides no benefits against
cancer, heart disease and stroke.

2) Studies also show that vitamin D deficiency is related to many illness.
Taking supplement protects against them.

You can determine if you have vitamin D deficiency with simple blood test.

~~~
pakitan
> 2) Studies also show that vitamin D deficiency is related to many illness.
> Taking supplement protects against them.

That's hardly a "rebuke". First, I'll note that you carefully used the word
"related" instead of "causing" or "a major factor". Then again, you omitted
"Studies show that..." from your second sentence, probably because there are
no studies showing that people with Vitamin D deficiency, taking supplements,
are doing any better than the ones that don't.

In fact there is a meta-study, quoted by the article, that suggests they
don't:

[https://www.thelancet.com/journals/landia/article/PIIS2213-8...](https://www.thelancet.com/journals/landia/article/PIIS2213-8587\(13\)70165-7/fulltext)

------
chx
Health wise , so much we are told turns out to be upside down.

Say, chlosterol. In 1977 the Framingham Study told us higher HDL levels and
lower LDL levels are associated with a reduced risk of coronary heart disease.
Not to mention later studies showing statin lowers LDL not only coronaries but
other cardiovascular diseases and even stroke
(10.1002/14651858.CD004816.pub5). Well, turns out higher cholesterol only
correlates with heart disease under 50 years old. Damning it all is a 2016
study showing above 60 actually higher LDL correlates with longer life... And
then it turns out though niacin brings down your cholesterol but has no
effects on cardiovascular events. And then Pfizer abandoned a drug which
raised HDL -- but actually raised the risk of such events. Whopsie!
[https://www.nytimes.com/2006/12/03/health/03pfizer.html](https://www.nytimes.com/2006/12/03/health/03pfizer.html)
The whole good/bad cholesterol thing is total, absolute bunk science proven
wrong multiple times from multiple angles. (Hope I didn't get wrong the
various lower/higher things.)

Also, in general, evidence is mounting that _all_ food related studies are
useless simply because humans with different genomes (surprise!) react
differently to food and we do not understand yet which genes correlate with
which food causing what. I mean, this makes so much sense, imagine that
someone asserted that seven billion beings with different genetic composition
reacts the same to all foods. That's absolutely laughable and yet, you are
getting these advices of what to eat and what not to eat in general. What is
beginning to become clear is that we do not know _anything_ at all about how
humans react to the food they intake. First we started with trying to see how
they react to "fats", "carbohydrates", "proteins" and so on. But turns out
foods are not just those but also vitamins and then it turns out no matter how
you put together fats, carbohydrates, proteins and vitamins it still won't
resemble anything food like. We go to smaller and smaller components trying to
find the composition of food -- but it just doesn't work. So you have an
unknown on the food end and another unknown on the human end and yet we are
told to follow certain diets. Which of course change every decade or so when
it all falls apart.

------
crazygringo
So for those of us in the winter (like right now in NYC), what are we supposed
to do for health, to protect against the diseases whose rates are increased by
lack of sufficient sunlight?

If vitamin D supplements aren't the solution, are we supposed to get UV lamps
for daily exposure at home after getting out of the shower? Totally serious
question -- anyone got any ideas? I'm actually surprised the article didn't
cover it.

~~~
kovach
Vitamin D supplements do help your immune system, reducing respiratory tract
infections, and seem to help with some autoimmune diseases. There have also
been some positive findings regarding clinical depression, and improved bone
health.

Currently there is no evidence that they help with cancer or cardiovascular
disease, but that doesn't mean that someone who is deficient should not try to
solve that deficiency with supplements.

Dosing the supplements is the difficult part, ingested Vitamin D absorption is
different from person to person, and it's further complicated by variable sun
exposure and skin production. 4000 IU per day should be a safe dose, but it's
probably not enough with zero sun exposure during winter...

------
burlesona
So TLDR;

\- a bunch of studies have shown Vitamin D strongly correlates with health

\- however more studies show supplementation of Vitamin D does not give the
same outcomes

\- Thus probably Vitamin D is not the cause, rather just an indicator for sun
exposure, and sun exposure is what’s good for you

\- lots of research showing sun exposure has many befits and avoiding it has
high risks

\- as for melanoma, it’s less common than you think and the risk is mostly
sunburn not sun exposure in general

\- this is more serious for people with darker skin whose bodies are better
adapted to more sunlight and have much lower risk of skin cancer but need more
sunlight to get the health benefits

Conclusion: go outside a lot and get sun, just do it gradually and don’t shock
your system with sunburn. If you’re not getting sunburn then your melanoma
risk is very low while the other benefits are very high.

That is interesting to read, and it also feels really common-sense to me. I
definitely feel better when I’m getting good sun exposure, and I can feel it
in the winter when I’m not. Most interesting to me is the studies showing
Vitamin D supplementation is not effective for health benefits. That’s too bad
because my D levels tend to be low and I have supplemented in the past, but
not shocking because it’s never really felt different to me when
supplementing.

~~~
PKop
One other point to highlight: Many of the doctors quoted in the article
couldn't dispute the data (reminiscent of nutrition conventional wisdom) but
inexplicably advocated _not_ to get benefits mentioned from sun, but instead
take statins/blood pressure drugs.

This is ridiculous, and if one looks into the criticisms of these drugs,
mirrors the terrible advice peddled by same doctors as nutrition advice, to
the detriment of millions. Why does this mentality persist, always and
everywhere take blood pressure drugs? Madness.

~~~
burlesona
Well, I’ve come to see it that western primary care doctors main job is to try
and match your symptoms to a pill that can help.

I’m not trying to disparage all the doctors or say they do nothing else.

But if you look at it like that, then a lot of the behavior makes sense. “I
don’t know about sun exposure, but I’m confident this pill will help you, so
avoid the sun and take the pill.”

~~~
classichasclass
A more charitable view would be, "Currently I have better evidence in the
literature that this medication would be more helpful than sun exposure, which
in large quantities has more evidence of harm than benefit."

That's not an indictment of physicians, that's a recognition that our evidence
base is skewed (for a variety of reasons). But there is good evidence that at
least for some people, sun exposure above some level does more harm than
benefit. You're saying the average primary care doctor should just toss that
out. Who says this isn't the latest whim to be disproven in 20 years?

The evidence base for lifestyle interventions sucks because it's much harder
to measure and pharma has certainly been able to tip the scales, no question.
That should change and I hope it does. But when I have a patient come in and
ask, we go with what we've got.

~~~
pakitan
> A more charitable view would be, "Currently I have better evidence in the
> literature that this medication would be more helpful than sun exposure,
> which in large quantities has more evidence of harm than benefit."

That's indeed a _very_ charitable view. The more realistic view, in my
experience is "I just go with the mainstream as nobody got fired or sued for
going with the mainstream and I don't really have the time, nor the
inclination to keep up with the latest studies".

> Who says this isn't the latest whim to be disproven in 20 years?

A million years of evolution, spent in extreme sun exposure, without sunblock?

I've long suspected that the "Always put on sunblock" advice is bollocks and
have never used the substance. Partly because of common sense (evolution of
human species) and partly because of simple observation. All my grandparents
and their relatives were raised in villages (and quite a few still live or
lived there till they passed away), with serious sun exposure, working on the
field, long before the age of sunblock. Yet, none of them had skin cancer.
Other cancers, diabetes, heart attacks, strokes, yes. Skin cancer - not a
single one of them. Why is that, if the sun is so dangerous?

And while you may dismiss my anecdata, note that the article says "outdoor
workers have half the melanoma rate of indoor workers"!! So, for me this isn't
the "latest whim", we're just going back to common sense.

------
jpiabrantes
I always thought there should have been an enormous evolutionary pressure for
humans to have different skin tones in different geographies. If sunlight is
bad for skin than we should all be black or tanned all the time. However, if
you don't live in a sunny area and you have a tan you might not getting enough
Vitamin D. Vitamin D must be very important in order to make us evolve to have
different skin tones and to tan according to the seasons.

~~~
gerbilly
The article mentions we store vitamin D for use in the winter.

It also suggests pale skin may have evolved to allow us to produce way more
vitamin D in the summer to compensate for cloudy winters.

So, the advice would seem to be, go outside in the sun during the summer if
you have pale skin.

------
amelius
I have a small blacklight installed in my home, and I turn it on a couple of
hours a week when I watch TV. It definitely makes me feel more relaxed, though
I'm unsure of the actual mechanism. Vitamin d is not the problem since I take
plenty of it in the form of supplements and fatty fish. Recently I discovered
that blue light can help break down bilirubin in the blood, and since I have
Gilbert's syndrome, that might be one explanation.

~~~
burlesona
According to this article, Vitamin D supplementation is showing not to “work,”
and the theory is that the correlation with health is actually as a marker for
UVB exposure. If your black light is putting out UVB then maybe that’s what’s
helping you?

~~~
zenexer
Pretty sure they mostly (entirely?) put out UVA.

~~~
burlesona
Interesting. According to the article that’s the “bad” UV. I wonder if there’s
a market for UVB lights?

~~~
groestl
Sure! [https://en.wikipedia.org/wiki/UV-
B_lamps](https://en.wikipedia.org/wiki/UV-B_lamps)

Or do you mean market as in "consumer market"?

~~~
crazygringo
Is there a consumer market?

A quick search on Amazon reveals UVB lamps are mainly either expensive ($250)
and for people with skin problems, or else cheap and low-powered ($30) for
reptiles.

There doesn't seem to be anything for a kind of full-body health use?

------
nemetroid
I found the tabloid-style writing very difficult to read, and it did not
inspire confidence in the content of the article.

------
popinman322
I find it odd that Examine.com[0] hasn't been mentioned yet.

There have been studies of vitamin D supplementation; these have been
specifically about supplementation and not just correlation with blood levels
of vitamin D.

I'm sure that sun exposure has additional effects past vitamin D production
given how messy biology is, but it's not clear to me that unprotected sun
exposure is the best way to get those additional effects. For example, if
blocking UVA and letting in some amount of UVB gets the benefits of both
sunscreen and sun exposure, then I'm all for it. However, it doesn't seem like
we have enough information to make an informed decision yet.

[0]
[https://examine.com/supplements/vitamin-d/](https://examine.com/supplements/vitamin-d/)

------
wolfv
Dr. Greger has a different take on the data. From
[https://nutritionfacts.org/video/the-risks-and-benefits-
of-s...](https://nutritionfacts.org/video/the-risks-and-benefits-of-sensible-
sun-exposure/) (transcript and sources cited are below the video)

Concerning the Swedish study: Why would those that run around outside enough
to get skin cancer live longer? Maybe it’s because they’re running around
outside. More exercise may explain why they live longer. And here in the U.S.,
more UV exposure was associated with a shorter, not longer, lifespan.

Estimates about vitamin D preventing internal cancers are from intervention
studies involving giving people vitamin D supplements (not exposing people to
UV rays).

------
paavoova
Related: many of the components of sunscreen break down into free radicals in
the process of absorbing UV, which are in effect (but perhaps not in practice)
more damaging than UV exposure itself.

Quick source I dug up, but there's many more (and the industry appears to be
aware of this issue and is doing R&D): "Sunscreens Inadequately Protect
Against Ultraviolet-A-Induced Free Radicals in Skin: Implications for Skin
Aging and Melanoma" [1]

[1]
[https://www.sciencedirect.com/science/article/pii/S0022202X1...](https://www.sciencedirect.com/science/article/pii/S0022202X15304437)

------
qwerty456127
According to another research[1] vitamin D supplementation actually changes a
lot of taken in adequate (by orders of magnitude higher than the official RDA)
doses regularly (and it also affects mood). So I conclude that what we need is
to also supplement nitric oxide, not just vitamin D alone.

I had never feared sun and don't even use sunscreens but I neither live in a
particularly sunny area nor have enough spare time for regular sunbathing so
supplements still are the only way to get enough.

[1]
[https://news.ycombinator.com/item?id=15867918](https://news.ycombinator.com/item?id=15867918)

------
thisismyusernam
I was really enjoying this article, which is intelligently written (even
though it's obvious the author has made up their mind and is trying to
convince me, I happen to agree with them). That is until this line:

> _From its inception in the mid-1800s, margarine had always been considered
> creepers, a freakish substitute for people who couldn’t afford real butter._

When did "creepers" become a word journalists can use in a non-ironic way?

------
Eli_P
Wanna share my experience, the TL;DR is that if you feel well you shouldn't
expose yourself to the sun or use parasol or sunscreen, because only narrow UV
spectrum is good, and sun doesn't care.

I've had a severe form of psoriasis, majorly on scalp. Over 1/3 scalp looked
like it had been rubbed with a sandpaper to near-bleeding sores. I tried to
different docs, nobody told me what it is, I had no option but to do my own
research.

I found that it can be treated with ultraviolet, but not all of UVs are good
for you, there are UVA, UVB and their sub-spectrums. The only good for health
UV is UVB with a narrow peak at 310nm wavelength. Those tanning beds for
bronze effect are wide band UVA+UVB and not good at all neither for vitamin D,
nor for your health in general.

So I had bought a UVB 310nm medical lamp, shaved my head, and started using
UVB since june, it's been a half year experiment on myself. I started with
long, over 10 minute sessions to figure out a limit where I do get burned (>10
minutes). Later I reduced down to 5 min, two times a week, and almost haven't
used UVB recently. I don't have vitamin D blood meter, my criteria is a state
of my skin, i.e. absence of pain on palpation, less itching, no bleeding
sores, no reddening. Looks like UVB works for me, what I can tell from my
experiment.

In comparison with sun, UVB lamp with timer showed to be more safe, IMO. Three
hours outdoors w/o sunscreen gives a sunburn very likely; but a 5 min/day UVB
lamp exposure seems to be safe.

I have a few tiny colored skin patches over body, didn't cover them or
anything, just ignored them; they have become less distinguishable after UV.
However, if you have patches like birthmarks, you must track their borders.
When borders become blurred, that's a not good sign, you gotta them checked by
your dermatologist. I think there could be some app to track colored skin
patches, there is a bunch of open source libs for that[1].

[1]
[https://github.com/search?q=skin+cancer](https://github.com/search?q=skin+cancer)

------
djohnston
if this turns out to have weight im going to need to switch my routine, but
i'll probably continue to use sunscreen on my face (but maybe not my arms
anymore). the anti-aging effects are important to me, but particularly on the
face, so there might be a nice middle ground here, as long as you're wearing a
t-shirt.

~~~
ip26
Protecting the face is rational, for many people it gets the most sun exposure
of any part of your body. Heard from my dermatologist two of the most common
skin cancer locations in our community are the lower lip and lower eyelid,
which of course are two facets of your face that are most perpendicular to the
sun at peak UV hours.

I figure, and this is just me, that if you want to get sun exposure, it's
probably best to expose more skin for less time. If the risk is LNT, it's all
the same. If it's not, you lower the total risk.

~~~
djohnston
what does LNT mean?

------
rb808
There was a similar article in Australia a few months back
[https://www.smh.com.au/lifestyle/health-and-wellness/here-
co...](https://www.smh.com.au/lifestyle/health-and-wellness/here-comes-the-
sun-defending-our-summer-rays-20181120-p50h2j.html)

------
jackfoxy
How much are UVA and UVB blocked by the atmosphere in higher latitudes during
winter months? UVB is blocked by the ozone layer, so I would expect in winter
even less reaches the Earth's surface.

------
anotherevan
Whilst I understood the analogy, a part of my brain that dislikes poorly
worded headlines thought to itself, "But sunscreen tastes terrible on toast."

------
benj111
So everything in moderation, including sun.

Are there any sensible exceptions to that rule?

~~~
jdminhbg
There are no exceptions because it’s a tautology. What’s moderation is defined
by what’s good for you. Nobody recommends fentanyl in moderation.

~~~
benj111
Not necessarily.

Its potentially true that consuming more of a veg increases health, without an
upper bound, or at least an upper bound above 'moderation'.

That doesn't fit in with your definition of moderation, but I would say
moderation has both an upper and lower bound.

~~~
jdminhbg
That's exactly the tautology: "Moderation" is "the amount that is good for
you." So there are no exceptions to "moderation is good for you." How else
would you define "moderation" in this context without a reference to the
amount of something that is beneficial? It's not as if "moderate" is an amount
that exists out of context that can be applied to both donuts and broccoli
without knowing which one of those is good for you.

~~~
benj111
Moderation: 1. the quality of being moderate; restraint; avoidance of extremes
or excesses; temperance. [1]

A 10kg portion of broccoli might be better for you than the usual recommended
portion. I would not say that's a moderate amount of broccoli though.

[1]
[https://www.dictionary.com/browse/moderation](https://www.dictionary.com/browse/moderation)

Edit: Also there isn't really a healthy amount of doughnuts you can eat, so by
your definition, a moderate amount would be zero. Which isn't really what the
'everything in moderation' rule means.

------
pcvarmint
I have osteomalacia, and I take Vitamin D, Calcium and Alendronate for it. I
have suffered multiple spontaneous bone fractures.

There is not enough sun where I live (Seattle), so unless I go to a tanning
bed, I need to get my vitamin D through supplements.

Survey of literature:

[0] [https://sciencebasedmedicine.org/the-rise-and-inevitable-
fal...](https://sciencebasedmedicine.org/the-rise-and-inevitable-fall-of-
vitamin-d/)

[1]
[https://link.springer.com/article/10.1007%2Fs11606-016-3645-...](https://link.springer.com/article/10.1007%2Fs11606-016-3645-y)

[2]
[https://www.jabfm.org/content/22/6/698.long](https://www.jabfm.org/content/22/6/698.long)

[3]
[https://www.researchgate.net/publication/290490087_Evaluatio...](https://www.researchgate.net/publication/290490087_Evaluation_of_knowledge_practices_of_vitamin_d_and_attitude_toward_sunlight_among_Indian_students)

[4]
[https://www.thelancet.com/journals/landia/article/PIIS2213-8...](https://www.thelancet.com/journals/landia/article/PIIS2213-8587\(18\)30265-1/fulltext)

[5]
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5986441/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5986441/)

[6]
[https://www.bmj.com/content/362/bmj.k3225](https://www.bmj.com/content/362/bmj.k3225)

[7]
[https://www.bmj.com/content/355/bmj.i6201](https://www.bmj.com/content/355/bmj.i6201)

------
guelo
The human evolution argument is interesting to think about because humans are
the only fur-less mammals so any advantages to sun exposure are unique to us.

~~~
yesenadam
>humans are the only fur-less mammals

Naked mole-rats beg to differ. Although yeah, I don't think they get much sun
exposure. But apparently they never get cancer, maybe we could learn from
them.

[https://en.wikipedia.org/wiki/Naked_mole-
rat](https://en.wikipedia.org/wiki/Naked_mole-rat)

------
angry_octet
This is worse than pseudo science, it is complete mumbo jumbo, totally
misrepesenting and misquoting sources.

To think that the author has been selected as an MIT Science Journalism fellow
is truly mind boggling.

[https://ksj.mit.edu/dispatches/2017/12/07/this-years-
fellows...](https://ksj.mit.edu/dispatches/2017/12/07/this-years-fellows-
rowan-jacobsen/)

I can truly say that I look forward to reading of the author's death from
melanoma.

~~~
frereubu
You're living up to your user name, but I dislike reading someone wishing
death on someone else, particularly on HN, from which I expect better. Like
the other reply, I would also be interested in a more thoughtful rebuttal
rather than this kind of vicious ad-hominem attack.

~~~
angry_octet
When you live in a culture that used to worship the sun and many friends and
relatives have died and or been scarred by skin cancer, you lose tolerance for
people pooh poohing UV exposure. Blatantly misrepresenting advice as he does
(saying sun exposure is recommended) is absolutely ghastly.

I rate him just a tad less awful than Andrew Wakefield, the anti-vaxxer.

------
martokus
To;Dr: As with anything, balance is needed. Use your judgement wisely.

~~~
zeroname
That's not the takeaway at all.

The article basically insinuates that you shouldn't use sunscreen, that you
should expose yourself to the sun for health reasons and that Vitamin D
supplements are actually useless.

~~~
in_cahoots
Insinuates is the correct word here, as the article dances around the point
without providing much evidence. I can believe that people with sun exposure
tend to be healthier. But at no point does the author make the case that these
people would be even healthier if they didn’t use sunscreen. The link is
tenuous at best, and the whole sunscreen part seems thrown in to genrerate a
headline.

~~~
beatgammit
Eh, the author did give some examples of bad chemicals in some sunscreens, so
it's possible that there are negatives to using them.

Here's what I took away:

\- don't use sunscreen most of the time (though if you care about aging
effects, go for it on your face) \- avoid getting sunburns, and use sunscreen
as necessary given your desired time in the sun \- check labels of sunscreen
and get familiar with the common active ingredients

That's basically what I do already, though I'm going to make an effort to
spend more time in the sun because I work at home, and therefore get minimal
sun exposure normally.

------
projektfu
This article breaks Betteridge's law. The answer is not "no", but it might not
be "yes". In fact, the article promotes the viewpoint that sun exposure is
actually good for you, whereas butter is probably not essential.

If the sunscreen recommendations turn out to be too strong, this would be good
news for me, as I have never liked having to apply sunscreen and dislike the
scolds who push it on me when I don't feel I need it. But the article glosses
over the fact that people who tend to burn rather than tan get more melanomas,
and that melanoma can be a very insidious cancer. So, if I know I'm going to
get a lot of exposure (beach, air show, whatever) I am going to use sunscreen
to prevent burns.

~~~
mrfusion
I propose mrfusions law: in any discussion of an article with a headline
ending in a question, someone will mention Betteridge’s law.

~~~
projektfu
I find it helpful to know if the answer is no. Betteridge's law suggests you
can avoid reading the article because the headline writer is trumping up the
findings.

------
chiefalchemist
The new margarine? Nah. No one was ever a fan of margarine. Feels more like
the new sugar. Public was told to give up X (fat) in favor of Y (sugar) only
to find said recommendation was paid for by Industry Y.

The species has survived this long for a reason. What Mother Nature has to
offer us is good for us. Why do we keep believing we can get it more better?

------
purplezooey
Everything is the new smoking. Ambien. Deli meats. Roasted things. Now
sunscreen. Are we supposed to live in a hobbit hole and eat boiled roots?

