6 ms·
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 wit
by alexandercrohde 8y ago
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.
- jcims 8y agoThanks so much, I was interested in the content but something about the article rubbed me the wrong way and I couldn’t make it through.
- raverbashing 8y agoNice summary It usually goes as "Vitamin D is not useful for healthy individuals" which is a nice example of circular reasoning (probably because they get enough sun exposure or have good levels of Vit. D from other sources) Oh yeah and tests checking Vitamin D's effects on things it was never claimed to help, like "found no impact on cancer, heart disease, or stroke." (Maybe cancer, but still) You will still get some Vit D through sun even with sunscreen on > Yes, but skin cancer kills surprisingly few people: less than 3 per 100,000 in the U.S. each year. Tell that to people in Australia or some other country directly below the Ozone layer hole But the news that production of NO is more important than Vit D is certainly interesting
- deleted 8y ago[deleted]
- beardedwizard 8y agoAustralia and New Zealand recommend direct sun exposure in the article. They are telling us, it turns out.
- raverbashing 8y agoDirect sun exposure when the UV index is under 3 That's before 9am or after 6pm around this week https://uv.willyweather.com.au/nsw/sydney/sydney.html https://uv.willyweather.com.au/nsw/sydney/sydney.html
- petecox 8y agoYep and that's a UV index of 13 [Extreme] even whilst cloudy. Australia and New Zealand have the highest melanoma rates in the world. We thus have a paranoia of "taking care not to burn", during office hours when UV is most intense.
- sornen 8y agoThe problem here is that UVB levels, required for vitamin D synthesis, decrease dramatically before 9am and after 6pm, whereas UVA does not. The best option for vitamin D synthesis is short sun exposure around midday.
- nazgul17 8y agoThat's a misconception, if I remember correctly. The ozone layer is over Antarctica. UV levels here (Australia) are high because the air is quite dry and clean (so I have heard). During summer (i.e. now) the UV index reaches 13 daily.
- raverbashing 8y agoSee the image: http://www.abc.net.au/science/articles/2008/09/17/2367117.htm?site=science/talkingscience&topic=enviro&listaction=unsubscribe http://www.abc.net.au/science/articles/2008/09/17/2367117.ht... It seems to vary over Australia but I'm not sure how far from the normal values this is
- hyperpape 8y agoAs 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 8y ago> 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 8y agoThe 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 8y agoAnd vice versa - consider migration from Central America to Chicago or North Africa to Stockholm.
- hyperpape 8y agoI don't think "refined" matters, except so far as once you refine sugar, you can add it to all kinds of foods, driving consumption up. That's exactly my point--eating some fruits or honey is good for your health when every calorie is valuable. Eating tons of sugar when it's cheap and added to everything is bad for your health. Just because eating some sugar was helpful in the past doesn't imply that our bodies have evolved to process arbitrarily large amounts of sugar with no ill effects whatsoever.
- guelo 8y ago10. The dermatological associations of Australia, New Zealand and Britain contradict the American one by recommending sun exposure in moderation.
- m-i-l 8y agoYes, e.g. for UK: "Most people can make enough vitamin D from being out in the sun daily for short periods with their forearms, hands or lower legs uncovered and without sunscreen ... you should be careful not to burn in the sun, so take care to cover up or protect your skin with sunscreen before your skin starts to turn red or burn. People with dark skin ... will need to spend longer in the sun to produce the same amount of vitamin D as someone with lighter skin."[0] [0] https://www.nhs.uk/live-well/healthy-body/how-to-get-vitamin-d-from-sunlight/ https://www.nhs.uk/live-well/healthy-body/how-to-get-vitamin...
- kingofhdds 8y agoFirst of all, thanks, your summary is literally better than the article itself :-) P.1 is not correct (it correctly reflects the article contents, but not factually correct). Research mentioned states vit. D supplements doesn't seem to reduce risks of cancers, and cardiovascular diseases - which doesn't mean they aren't useful.
- darawk 8y ago5 is not quite right. According to the article, your melanoma risk does rise with sun exposure, but for some reason that is not explained, you are substantially less likely to die from it if you have more sun exposure. The article does not clarify how much the incidence increases though, and whether it offsets the 8-fold decrease in mortality.
- ajmurmann 8y agoI thought the article mentioned early on that the issue are sunburns. If for example you are a pastry, white person usually hacking indoors and then you suddenly go on vacation in the Caribbean and are in the sun without protection or adjustment period, that's a problem. If on the other hand you get a reasonable amount of sunlight year around that's what supposedly leads to better health outcome.
- darawk 8y agoYa it said that too. Moderate, frequent sun exposure seems to be the thing you want.
- bromuro 8y agoIt surprises me that people believe that margarine, a concentrate of vegetable raffinates fats, is healthier then butter. I believed it was common knowledge how bad margarine is for our body... at least in Italy, where we always use olive oil of butter - I don’t know anybody that would prefer margarine here!
- mikemotherwell 8y agoWas a few decades ago.
- rz2k 8y agoWith regard to sunbathing in Sweden, it sounds like the study was originally designed to track many variables for possible influence on blood clots. Tanning behavior ended up having a high correlation with lower all-cause mortality. I haven't looked into whether they controlled for variables like socioeconomic situations that allow for more suntanning, though that seems likely before publishing such a conclusion. What seems less likely to have been controlled when just looking for contributors to blood clots, would have been whether the subjects' skin tanned easily. Many light-skinned people do not easily tan at all, and even complain that their skin seems to go straight from white to red. In Sweden, there are many people who do tan easily in spite of having very light skin. It seems like that could very easily have been a confounding factor. The genes that make you bun easily or tan easily seem like they would have a significant effect on ones decision on whether to sunbathe or not. Likewise, I can imagine that those genes could also affect all-death mortality rates.
- katbyte 8y agopersonally I used to burn pretty easily (light skin, freckles) When I was much younger and spent most my time indoors. However I took up multiple outdoor activities and after quite some time in the sun it’s rare for me to burn even after hours in the sun with no sunscreen, and if I do burn it heals fairly rapidly. So outside genes there may be some sort of adaptation going on.
- copperx 8y agoTrue. Another thing to consider is that regardless of the health effects, sun exposure ages your skin; sometimes dramatically so. A compromise would be to use sunscreen on your face and neck (since they don't produce that much vitamin D anyway, if I'm remembering a study correctly), but leave the rest of your body uncovered. Perhaps add sunscreen to your hands too.
- Lazare 8y agoYes. The upshot of the article seems to be: 1. Vitamin D supplements do nothing 2. Regular safe sun exposure has many positive benefits and very few negatives (a very very small chance of getting a type of cancer that is normally deadly, but for reasons we don't fully understand, is much less deadly to people who get regular sun exposure). 3. Avoiding sun exposure entirely has many negative effects and will kill you. 4. Intermittent extreme sun exposure (the kind that causes sunburn) actually is terrible, and will lead to the bad skin cancers that will actually kill you. 5. Sunscreen may do more harm than good, both to people and the environment. It's certainly not a magic bullet. 6. Sun exposure needs (and risks) vary heavily by skin colour, and while it's good for everyone to get regular safe sun exposure, it's critical for people with darker skin. In other words, if (like a lot of Americans) you take vitamin D supplements, avoid the sun most of the year, then slather on a ton of sunscreen for your once a year summer vacation, you're basically doing everything as wrong as you possibly can, and getting the worst of all worlds. And apparently this is supported by new research, and most countries have already adopted it, with the main outlier being the US, primarily due to industry pressure/greed/inertia. Sounds plausible, at any rate.
- ramblerman 8y ago> then slather on a ton of sunscreen for your once a year summer vacation, you're basically doing everything as wrong as you possibly can, and getting the worst of all worlds. Agreed but Sunscreen might still be better in that case. See point 4 (Intermittent extreme sun exposure (the kind that causes sunburn) actually is terrible). These people would be sure to get bad sunburn if they lay on the beach all day only 2 weeks out of the year.
- Lazare 8y agoQuite right, I didn't phrase that well. Of course, even if unhealthy sun exposure + sunscreen is better than unhealthy sun exposure on its own, it doesn't mean it's better than avoiding the unhealthy sun exposure patterns at all. I feel like there's a fair bit more to figure out here. A lot of us live far from the equator with jobs and hobbies that keep us indoors a lot. Observing that regular safe sun exposure is healthy is great, but I don't even like beaches. It's easy to criticise bad ideas (vitamin D supplements, tanning beds, etc.) but harder to figure out the best compromise.
- nosefrog 8y agoTo add some "anecdata" to the discussion, vitamin d supplements changed my life. I learned that my vitamin d levels were super low (7 ng/ml, when less than 20 ng/ml is deficient) from a routine blood test. Within a month of taking vitamin d, my afternoon fatigue went away, it became much easier to wake up in the morning, my energy levels generally increased, and my mysterious colds that I was getting every 1-2 weeks that winter stopped. I strongly recommend getting your vitamin d levels checked!
- crazygringo 8y agoYes, I had low levels as well in the winter only, and supplements made a big difference in my mood in the winter (and I verified my levels were back to a normal zone). So while these studies may be showing that vitamin D doesn't affect cancer, heart disease or strokes... that doesn't mean it's useless. YMMV.