I haven't dug into this, and, for the record, I do think vitamin D is likely an important factor here. But I find the two charts to be very worrisome.
Their claim of a very high p value and significant effect is VERY strongly influenced by a single outlier. It's not even close. On this unlabeled graph, I think x axis is vitamin D levels and y axis is deaths per million. They've got ~16 data points in the range of 0-10 deaths, one point at ~20, and one at 65. If you removed the 65 point the line would get a hell of a lot less convincing.
This study is not exactly rigorous. There doesn't appear to be any controls for age or health risks or anything else. Their methods are literally to take worldometers data and vitamin D concentration data per country from the European Calcified Tissue Society and plug those values into a t-test calculator.
When HN was in a tizzy over p-values a year or so ago, this is what people were concerned about. It's below .05, so what?
Not saying there is or isn't an affect on covid by vit D, but this isn't the study to prove it.
> Their methods are literally to take worldometers data ... and plug those values into a t-test calculator.
I have seen more papers like this recently. It seems to have become a popular format in hypothesis discovery, usually followed up by others with better methodologies.
They become a problem if the popular press takes the results to publish out of context, or if they enter meta studies.
It's so strange to me that these studies seem to generalize findings (eg results by country) when one of the key biological factors for how we get vitamin D is skin colour. And at its most basic relationship, the whiter ones' skin, the better one is at generating Vitamin D from sunlight. Perhaps it points to another way in which this disease could disproportionately affect persons of colour?
If anyone has any literature that explores it more I'd love some direction.
> It's so strange to me that these studies seem to generalize findings (eg results by country) when one of the key biological factors for how we get vitamin D is skin colour.
They bypass skin color by just measuring levels of Vitamin D directly. This study doesn't care how you got the Vitamin D, it just cares how much you have.
There are tons of problems with this study, but failure to look at skin color isn't one of them.
Even if skin color is a predictor of vitamin D levels, this study doesn't need to predict vitamin D levels because they used measured vitamin D levels.
> this study doesn't need to predict vitamin D levels because they used measured vitamin D levels
If darker-skinned people have, on average, lower vitamin D levels, then measuring vitamin D levels proxies for skin color.
So if the underlying cause is e.g. access to healthcare or stress or exposure to airborne particulates, and those correlate with skin color, those will also correlate with vitamin D levels.
One could thus find vitamin D levels relate strongly to outcomes. But increasing vitamin D has zero effect on the outcome. Because it's not the cause. (We see this a lot with poverty correlates in education.)
> If darker-skinned people have, on average, lower vitamin D levels, then measuring vitamin D levels proxies for skin color.
"Proxies for" doesn't have a scientific meaning that I'm aware of, so I can't be sure that I understand what you're saying.
If what you're saying is that vitamin D levels are correlated with skin color, true, but irrelevant to this study.
If what you're saying is that the (poorly substantiated) correlation between Covid19 and vitamin D can be used to claim a correlation between Covid19 and skin color: no, because it's quite possible that vitamin D levels have no effect on Covid19 in people with darker skin, but a huge effect on Covid19 in people with light skin. You also have to keep in mind that your errors multiply across different correlations: the error margin of correlating Covid 19 with skin color via this method is the error margin of correlating Covid19 with vitamin D and the error margi of correlating vitamin D with skin color.
If what you're saying is that the (poorly substantiated) correlation between Covid19 and vitamin D can be used to establish a causal relation between Covid 19 and skin color, no, because in addition to the previous problems, you're ignoring that there at least 10 confounding factors besides skin color which also have correlation with vitamin D levels:
1. Latitude
2. How much time you spend outside
3. Which time you spend outside
4. Clothing
5. Sunscreen
6. Liver function
7. Diet
8. Supplementation
9. Cloud cover over time
10. Season
If what you're saying is that this study can be used to establish a causal relation between Covid19 and skin color: in addition to all the previous problems, this study can't even really be used to establish a correlation between vitamin D and Covid19, so do we really need to pile on more logical fallacies than are already present?
By the definition on that page, vitamin D isn't a proxy for skin color.
> In statistics, a proxy or proxy variable is a variable that is not in itself directly relevant, but that serves in place of an unobservable or immeasurable variable. In order for a variable to be a good proxy, it must have a close correlation, not necessarily linear, with the variable of interest. This correlation might be either positive or negative.
> Proxy variable must relate to unobserved variable, must correlate with disturbance, and must not correlate with regressors once disturbance is controlled for.
Skin color isn't an unobservable or immeasurable variable, and it does correlate with regressors once disturbance is controlled for.
I believe what they are saying is that if their is a correlation between skin color and vitamin D levels (people with darker skin have less vitamin D) and there is another reason people with darker skin have poor outcomes (let’s say bad healthcare), it would make any conclusion that the vitamin D levels have a causal relationship to covid-19 outcomes less likely.
To account for this, you would need to control for skin color.
Huh? The authors of this (flawed) study are making the claim that Vitamin D deficiency correlates with negative outcomes from COVID-19.
They are doing this by using public measures of country-wide serum-based Vitamin D deficiency rates and COVID-19 outcomes.
How is "where the Vitamin D comes from" relevant at all to this particular correlation? It might be relevant if you're interested in a correlation of Vitamin D deficiency and anything having to do with the sun -- but that's not the correlation they're making here.
Say people in a neighborhood are getting cholera. Some of the residents collect rainwater, while others walk to the Broad Street well. The people who use the well are better hydrated at baseline, and you are exploring the correlation between hydration and cholera. Is where the water comes from relevant?
You're struggling here because you're not being specific enough in your reading and you're not being specific enough in your writing either. Is where the water comes from relevant to what? You need to be more specific.
Is where the water comes from relevant to the correlation between where the water comes from and cholera? Tautologically yes.
Is where the water comes from relevant to the correlation between hydration and cholera? No.
The reason you need to be more specific is that these are completely different experiments:
If you want to see whether where the water comes from is correlated with cholera, you might observe everyone who goes to the well and everyone who collects rainwater for 30 days, and see whether more from the well group or more from the rainwater group develop cholera. Note: you aren't collecting any data in this experiment about how hydrated these people are.
If you want to see whether hydration is correlated with cholera, you might randomly select 30 people and measure how much water they collect every day for 30 days, and plot that against whether they develop cholera. Note: you aren't collecting any data in this experiment about where these people get their water.
"Is skin color correlated to vitamin D absorption from the sun?" and "Are vitamin D levels correlated with Covid19 infection and severity?" are two completely different questions and two completely different experiments. And to be clear, they aren't even connected by a common cofactor: "vitamin D absorption from the sun" and "vitamin D levels" are two very different things, which may not even be correlated in certain situations (that is to say, I may absorb very little vitamin D from the sun, yet have very high vitamin D levels--this could happen if I supplement or consume a lot of vitamin D in my diet). You cannot draw any conclusions about vitamin D absorption from the sun or skin color from this study, because it does not collect any data about those vitamin D absorption from the sun, and it does not collect any data about skin color.
You almost got my point, so I'll be a little more specific just for you.
> If you want to see whether hydration is correlated with cholera, you might randomly select 30 people and measure how much water they collect every day for 30 days, and plot that against whether they develop cholera. Note: you aren't collecting any data in this experiment about where these people get their water.
Your experiment is fatally flawed, due to the error described in your note. You would find cholera to be strongly associated with baseline hydration status--but that relationship is not causal, so your results would be misleading. An experiment not subject to this flaw would collect data about where people got their water, and control for that statistically.
Identifying confounding factors is a fundamental part of experimental design, because association alone is poor evidence of causation.
> Your experiment is fatally flawed, due to the error described in your note.
That's not an error, and the experiment isn't flawed. An experiment is only flawed if it fails to answer the question it's asking. You see this as a flaw because you're asking the question, "What causes cholera?" You're correct that the experiment doesn't answer that question, but that's not the question the experiment is asking. The experiment is asking, "Is where the water comes from relevant to the correlation between hydration and cholera?"
It's easy to say, "Well, that's the wrong question", with hindsight. You know that where the water comes from is a confounding factor because it's 2020 and we've known what the cause of cholera is for most of a century. But when you're designing experiments, you can only guess at what the right questions are, and you don't always know what the confounding factors are. Asking the wrong questions doesn't mean your results are wrong, it just means that you can't draw very broad conclusions from those results.
Broad conclusions are drawn from a large number of experiments. The broader the conclusion, the more experiments are necessary to prove it. Even your experiment which correlates hydration and cholera controlling for water source doesn't tell us what causes cholera. In 2020 we know that cholera isn't caused by well water--I have a Nalgene full of well water I've been drinking from since this morning and I don't think I'm in any danger. Is your experiment flawed? No! It just isn't asking the right question, yet! But it's a step toward the right question.
In practice, the way this would work is:
1. You do the hydration experiment and discover a correlation between cholera and hydration. Great! Maybe people are getting cholera because they drink too much water!
2. You design a new experiment where you try reducing water intake as an intervention. You randomly select 30 people to be in the experimental group and 30 people to be in the control. You tell the 30 people in the experimental group to drink 8 cups of water per day. Suddenly, your the benefits of drinking less water disappear. So now you know that there's a confounding factor which was present in the first experiment, but not the second.
3. You go back to inspect the first experiment and try to see what other variables might have been correlated with water consumption, and try to design an experiment that asks a different question. You might have to do this a bunch of times before you finally notice the well/rainwater difference, and decide to design an experiment asking about that.
That doesn't mean all your experiments were flawed! On the contrary, each of those experiments gave you a tiny bit of information which allowed you to eliminate a possibility or otherwise refine your questions until you found the exact right experiment to ask the right question.
> Identifying confounding factors is a fundamental part of experimental design, because association alone is poor evidence of causation.
Sure, but the only way you identify confounding factors is by doing experiments.
All of this is one huge unrelated tangent, because skin color isn't a confounding factor when the question is, "Is vitamin D level correlated to Covid19 infection and severity?"
> Is where the water comes from relevant to the correlation between hydration and cholera? No.
In the specific example provided. Yes, of course it is.
Rainwater is close to pure water, drinking distilled water distroys cells in gut and causes diarrhoea, same as cholera does. Therefore this is a basic source of error in the experiment that should be controlled.
> In the specific example provided. Yes, of course it is.
> Rainwater is close to pure water, drinking distilled water distroys cells in gut and causes diarrhoea, same as cholera does. Therefore this is a basic source of error in the experiment that should be controlled.
1. Where did you get this bizarre claim? They sell distilled water in stores for drinking. I've drunk it. It didn't cause me diarrhea, certainly not "same as cholera does". Cholera causes such severe diarrhea that people die of dehydration from it. There's some evidence that it slightly leaches minerals from your body, but that's a far cry from it causing such severe diarrhea that it might literally kill you.
2. Even if what you are saying were true (which is isn't), that would make it a confounding factor or regressor, not a source of error.
3. And even if it were a regressor, that doesn't invalidate the experiment. You can still draw a correlation between hydration and cholera, you just can't conclude that hydration causes cholera. Which is fine, because almost any experiment you do is going to require further experimentation to be able to establish causality.
Put another way, this experiment asks the wrong question, but asking a bunch of wrong questions is part of the process of science.
The cause of cholera has been known for about a century, so it's easy in hindsight to design an experiment that proves cholera is caused by microbes in fecally-contaminated water. But that's not how science works. In science you're asking questions where you don't know the answer, so you start by asking very narrow questions, like "Is cholera correlated with hydration?" and slowly expanding to questions like "Is cholera still correlated with hydration if you restrict hydration as an intervention?" or "Is cholera still correlated with hydration if you control for water source?" All of these are valid questions around which you can design valid experiments. You just have to understand that when you ask a narrow question you get a narrow answer. None of these experiments conclusively identify the cause of cholera--even the experiment you proposed.
My interpretation (which might be wrong) of the study abstract is that it is known that Vitamin D levels vary in different regions, and it's also known that COVID-19 mortality varies. And these things are the motivation to study whether Vitamin D levels have a connection to mortality. So they measured Vitamin D levels and measured mortality and looked to see if there is a correlation.
I did see that mentioned as a theory a few weeks ago. My best guess is that in the United States especially, it's a combination economic/socitial factors and vitamin D deficiency that's making the virus have higher mortality in populations of racial minorities with darker skin.
Here's a study that looked at vitamin D levels and found that they're significantly lower in both people with darker skin, and (independently of skin color) those who are overweight. https://www.jabfm.org/content/29/2/226
> My best guess is that in the United States especially, it's a combination economic/socitial factors and vitamin D deficiency that's making the virus have higher mortality in populations of racial minorities with darker skin
African American communities are hardest hit because of genetic and especially cultural practices which predispose them toward obesity, high blood pressure, heart disease, etc. Further, let's not pretend that African American communities have the same level of respect for authority (i.e. following recommendations/orders) as other groups (though to some degree that disdain may be justified, but that's another discussion).
I'm actually pleased it was a study on white folks because since we know that this disease disproportionately kills blacks in the US, and blacks tend to have higher rates of vitamin D deficiency (because of the sunlight/skin pigment issue you mentioned) that we were merely seeing a reflection of the racial imbalance. This study suggests otherwise.
That said, there could be other confounding factors. COVID-19 could in fact "drain" vitamin D in some way. We know elderly people are disproportionately killed by the disease, perhaps vitamin D deficiency is more common amongst the elderly. Causal inference from observational data is tricky indeed.
That said, vitamin D supplements are cheap (for now). And most people don't get enough anyway. So people should take it.
That's one definition. It can also mean to carry someone off by force, to kidnap. "Carried away" is the root idea, but it doesn't have to be "by delight".
Because they are still deficient of vitamin D [1]:
> It is evident that, despite the location of Ecuador and the intensity of UV rays it receives throughout the year, Ecuadorian subjects have insufficient levels of vitamin D.
I wonder if it says they wear a lot of sunscreen. They’re on the equator and much of the country is at a very high elevation so the sun is particularly strong. When I was in Ecuador for a few months I went through more sunscreen than I had in my whole life up to that point. Without sunscreen I would get burnt to a crisp on an overcast day even when I didn’t spend much time outside.
This is a quick study, and there are lots of flaws in it.
That said, vitamin D deficiency is a real thing, and is especially common in as you get older. Vitamin D supplements are also pretty cheap.
It's not unusual to have to make quick decisions with little information. This study is enough to justify making sure that you have enough vitamin D, and probably to take reasonable dosages of supplements. You have to be careful, you can kill yourself with overdosages of vitamin D... it is a hormone and not technically a vitamin.
Vitamin D supplemenation is an easy and cheap thing to do, not harmful as long as you don't overdose, and there is some evidence here that could be helpful. So it is reasonable for the moment to take Vitamin D supplements, at least until we've had time to do more detailed studies.
There have been other studies into the use of Vitamin D to prevent the flu, where it has been shown to be very effective. I think there's a decent connection between contracting the flu and contracting Covid?
I don't know about other countries, but in Russia blood test for vitamin deficiency costs about $40 and can be
D done in any lab, which are very common in cities. Simple thing to do is to go and test for do you really have deficiency or not and then proceed with supplements program.
That's how I identified my deficiency and successfully fixed it by taking oral supplements.
The study from which they took average vitamin D levels per country is rather flimsy source to make reliable conclusions from. If you look it up, you'll see that the data is gathered from multiple studies with different methodologies.
And it seems they didn't control for various factors which could influence spread and mortality of the virus either.
Number of Covid cases and deaths reported across Europe mean wildly different things. Especially in early April.
Even if I look at today's numbers in my country, there's been only 30k cases officially. We know we could be off by a factor of 6, even though Switzerland did quite a bit of testing:
I know of at least one study in COVID-19 cases that suggested a correlation between mortality and Vitamin D levels [0], tested in patients rather than comparing national averages. That said, I'd like to see more tests in confirmed cases and even more than just mortality correlation, I'd like to see if it helps with long term lung damage.
> We found no clinical evidence on vitamin D in COVID-19. There was no evidence related to vitamin D deficiency predisposing to COVID-19, nor were there studies of supplementation for preventing or treating COVID-19.
> There is some evidence that daily vitamin D3 supplementation over weeks to months may prevent other acute respiratory infections, particularly in people with low or very low vitamin D status. This evidence has limitations, including heterogeneity in study populations, interventions, and definitions of respiratory infections that include upper and lower respiratory tract involvement.
The vitamin D deficiency is particularly interesting to me with respect to pregnant women and smokers. There have been cases of pregnant women who were unknowingly infected with Covid-19[1] and it seems there’s some evidence the smokers are less likely to be admitted to the hospital with a severe case.
I would expect both groups to have higher than average vitamin D regardless of their age, background, health issues. Pregnant women consistently take prenatal vitamins for months and (most) smokers consistently get daily sun exposure because they go outside to smoke. And from what little we know it seems both groups fare better when they are infected.
Is COVID-19 more severe because of a Vitamin D deficiency or does severe COVID-19 cause vitamin D deficiency? Or perhaps people with Vitamin D deficiencies also not get outside for enough sunlight or eat healthy enough, and poor diet/nutrition results in more severe symptoms of COVID-19?
> Of note, the hospitals tested D levels repeatedly and also had pre-admission levels. The author performed an analysis to determine whether the levels changed much within a patient and found that they did not for 95% of the overall cases examined, which then made up the 212 cases kept for analysis. The vitamin D levels used were pre-admission. Thus, though the data are associative, the reverse causality that the infection caused dropping D levels can be ruled out.
I’ve been thinking about reports like these for a while, and suppose you had a study that said 100% of all COVID-19 cases in the world are in people who live in areas with less than healthy air pollution. Does that mean the air pollution causes the disease? Because nearly everyone in the world lives in such an area.
It could be that Vitamin D levels are correlated with sun exposure, which improves health via a hormesis response to oxidative stress on the blood in the skin and eyes.
> Vitamin D levels are severely low in the aging population especially in Spain, Italy and Switzerland. This is also the most vulnerable group of population for COVID-19.
It could also be that age is the important factor here and that Vitamin D actually isn't relevant at all - as they said Vitamin D is low in all those populations already.
No, it is relevant because "a cause and effect relationship has been established between the dietary intake of vitamin D and contribution to the normal function of the immune system" & "The (EFSA) Panel considers that the role of vitamin D in the functioning of the immune system applies to all ages, including children."
Worth noting that in general and very roughly, at least 85% on average, of old people survive infection with Covid-19 a group which includes those in their 90s.
Sun also improves health by killing viruses that can cause illness, and by reducing time people spend enclosed in unventilated spaces, where they are prone to respiratory pathogens.
I’ve never bought the argument that the flu season is caused by people being indoors more (and then contracting or spreading a virus). Most people are still going to their jobs just as much, which is probably where they’d get it anyways.
Schools being closed might have an effect, though.
Anyways, n=1 but my immune system has seemingly greatly improved from vitamin D supplementation. When I get a cold now there’s at least a chance that I’ll only have major symptoms for a few days, instead of the usual 2 weeks.
If there's just correlation, then it makes sense. Odds are older people - especially those in nursing homes - don't get much sunshine and therefore would have lower vitamin D.
Alternatively, if there is causation where lower vitamin D levels make you higher risk of infection or a more severe infection, then forcing everyone inside (aka reduced sunshine) via lockdowns is the exactly wrong policy.
And if sunshine kills the virus in the first place, then the lockdowns are worse on another front. We should encourage people to hang out in the sun before going inside anywhere. It would be a form of decontamination.
Regardless, this is further encouragement to stay away from the NYC subway system!
My hypothesis is that COVID-19 is more severe because of a Vitamin D deficiency and old people are more likely to be deficient.
The discussion section references a study from 2017 which shows Vitamin D's helps protect against acute respiratory infections, especially those who are D deficient.
It mentions the countries with lower levels of vitamin D and higher mortality rates (Spain, Italy, Switzerland) also have an older population.
On a different topic: Vitamin D has been touted as this miracle vitamin but studies and trials have shown that it's not effective for improving cardiovascular health or bone density.
Posted this previously when the subject came up, but John Campbell, an nurse and educator in Northern England who's been doing daily Youtube updates on global Covid news since January I believe, has put out a few videos from time to time related to vitamin D:
He offers published studies as evidence to suggest vitamin D deficiency may play a partial role in explaining higher mortality rates among people with darker skin (other important social disparities notwithstanding).
Isn't it that when someone is sick or their health is detriorating, the first thing that happens is that their body stops producing Vitamin D? And since they are not able to go out from that point it further reduces vitamin D?
This is looking at population-wide measures of Vitamin D deficiency from before COVID-19, so...maybe the argument you're making is that these populations with lower Vitamin D were already sick and thus more prone to COVID-19?
Because they're not measuring post-COVID-exposure Vitamin D levels.
> maybe the argument you're making is that these populations with lower Vitamin D were already sick and thus more prone to COVID-19?
No, he's making an observation unrelated to covid. At any time you're sick your vitamin D production stops so you're deficient and then on top of that you don't feel good enough to go outside so your further deprived of vitamin D.
Most of us (computer people) are Vitamin D deficient and taking a supplement to get us up to the healthier levels is a good thing, but focusing on just one nutrient without taking all of nutrition into account is like focusing on fixing only one nasty anti-pattern while letting dozens of other anti-patterns continue unchecked.
Vitamin D supplementation is relatively harmless at reasonable levels, so advising it makes sense.
However, taking country wide averages is begging for confounding factors, right? I bet you could find a higher correlation with lots of things than Vitamin D, for example amount of per capita olive oil usage (Spain and Italy are #2 and #3), time that dinner is eaten (Spain and Italy both tend towards 9pm, vs 6:30 for Germany), etc etc etc. It doesn't prove anything and there isn't a proposed mechanism of action, so it's just correlation bingo at this point.
There was an article here just the other week suggesting that vitamin D could very well be not a supplement to, but rather a marker of, good health.
If it is true that Vitamin D is a marker of good health, and people with high levels of Vitamin D do well against the virus, this study suddenly turns out to be a lot less interesting.
I think people should be aware of sunlight and vitamin D.
Lots of old people never go out in the sun, and that could be a huge contributing factor.
From wikipedia[1]
Adequate amounts of vitamin D can be produced with moderate sun exposure to the face, arms and legs, averaging 5–30 minutes twice per week, or approximately 25% of the time for minimal sunburn.
For what it’s worth, I had an extremely severe vitamin D deficiency (8 nmol/L - not a mistake!) measured in mid summer, despite going outside 5hrs a week on my commute by bicycle. I’m pale and Scottish.
I now take a supplement every few days and my level is up to around 150. I feel much better now.
Point is, if anyone’s reading this and thinking they can’t be deficient because they are outside a lot, that is not a always the case.
I have been particularly amazed by the reported deaths in Singapore, which has been struggling with multiple outbreaks. To date, only 21 people have died from the virus there, supposedly, despite over 25K infections. That is a remarkable contrast to many other countries. Malaysia, Singapore's only land border neighbor, has nearly the same rate.
They also have only 288 reported cases, which is astonishingly low and hard to believe. But possible -- Taiwan is similar. Though Taiwan does not count as one of the warmer climates like Singapore or Malaysia.
Very few countries can give you an accurate death rate at this point.
If you look at mortality among demographics that were thoroughly tested, you can tell that the age distribution was definitely higher on the Diamond Princess than on the French aircraft carrier. That's about it.
I'm not sure why this trend isn't discussed more in the popular media. Seems quite significant, and is very easy to reproduce. Just scrape Google's covid-19 stats and join with a geographic coordinate source. A journalist could do this by hand with an Excel spreadsheet in about half an hour.
If this trend holds up, then as the Northern hemisphere hits summer, the death rates should plummet. On the other hand, in the Southern hemisphere as winter approaches the death rates will go up.
Iceland actually has Vitamin D deficiency levels comparable to a country such as Greece [1][2]. Supplements such as fish oil liver are in widespread use.
"It is often difficult to determine how much vitamin D supplementation is needed to obtain the “sweet spot.” For these reasons, you should routinely get your vitamin D levels tested and rely on dietary sources or supplementation to boost your levels when necessary."
In the UK, the NHS (National Health Service) recommends a daily vitamin D supplement of 10 micrograms (400 IU). In a previous discussion on Hacker News a few days ago, some posters mentioned this was a low and outdate dosage.
However, the NHS site also warns against taking more than 100 micrograms (4000 IU) of vitamin D. In the previously mentioned HN discussion, some posters stated they take more than this (some have been told to by their doctors).
What the NHS website says:
Taking too many vitamin D supplements over a long period of time can cause too much calcium to build up in the body (hypercalcaemia). This can weaken the bones and damage the kidneys and the heart.
If you choose to take vitamin D supplements, 10 micrograms a day will be enough for most people.
Do not take more than 100 micrograms of vitamin D a day as it could be harmful.
The calcium build up of the reason they often add vitamin K2 to vitamin D supplements. I am not qualified to say if it works at preventing the build up but it's often the stated rationale.
I don't know what you mean by "these studies" as the link is to only one study.
This study does a pretty questionable job of establishing that any amount of vitamin D levels reduces likelihood of severe infection. It doesn't even attempt to say what level of supplementation would lead to what vitamin D levels. So I think the answer to your question is a firm, "No."
It may be that people with low Vitamin D are low because of a combination of their skin tone and the amount of sunlight they get. This causes them to also be low on Nitric Oxide. You see the low Vitamin D as a marker, but it might not be the true cause.
The shelter in place is causing people to get less sunlight, so until we know more, I'd focus on getting more sun.
If that were the case you'd see significantly different infection and mortality numbers for the Nordic countries than for the rest of Europe since many people supplement vitamin D there.
Norway, Denmark and Finland seem to be doing relatively well, but Sweden's rates are pretty similar to France's.
Adequate sleep is very important to immune function. I should sleep more at night but its my most productive time. I started taking some vitamin D when all this started because a doctor recommended it. Granted I think if I just go outside into the sun a little bit I should have enough.
It is not merely that people are old that makes them susceptible to Covid-19. It is other factors that correlate with age that make them more susceptible. One of those factors could very well be lack of vitamin d.
Healthy people have healthy levels of Vitamin D. Sick people that ingest VitD will still get sick, vitamin D is a signal of healthiness, not something you can ingest to get healthier. Lose weight, eat meat, sunbath.
> Vitamin D levels are severely low in the aging population especially in Spain, Italy and Switzerland.
So.... all old people are unhealthy? Across the board?
And are you saying that sunbathing makes you healthy? That would be the closest link to Vitamin D, but I'd suggest sitting around outside doesn't actually mean you're healthy.
I'd delete this too. Supplementing Vitamin D is a good idea and promotes an overall healthier person. It'd be great if you could stop trying to spread misinformation.
> Vitamin D is a nutrient found in some foods that is needed for health and to maintain strong bones. It does so by helping the body absorb calcium (one of bone’s main building blocks) from food and supplements. People who get too little vitamin D may develop soft, thin, and brittle bones, a condition known as rickets in children and osteomalacia in adults.
> Vitamin D is important to the body in many other ways as well. Muscles need it to move, for example, nerves need it to carry messages between the brain and every body part, and the immune system needs vitamin D to fight off invading bacteria and viruses. Together with calcium, vitamin D also helps protect older adults from osteoporosis. Vitamin D is found in cells throughout the body.
You are misunderstanding basic physiology and thus implying that I'm wrong. The healthy body produces the Vitamin D it needs. The unhealthy ones that takes VitD as supplement are just wasting their money, there is no evidence that oral vitamin supplements raises the bioavailable nutrients we use. You didn't bring any evidence of that.
Again, no. Attempting to condescend to me about bioavailability and physiology is great, but a quick google search proves that (shock) _supplementing things makes them increase in the blood_
> According to our data, amounts of vitamin D3 increased in the blood serum of all treated animal groups in proportion to time, during vitamin supplementation, until the 7th day (Figure 3). As early as after 3 days of supplementation, microencapsulated and oil-based vitamin D3 increased vitamin levels in the blood by almost three times: The control level of vitamin D3 in the rat serum ranged from 36.49 ± 4.12 to 40.5 ± 3.05 nmol/L, meanwhile in the microencapsulated and oil-based treatment groups it got up to 143.35 ± 14.72 and 150.85 ± 35.77 nmol/L, respectively. The highest vitamin D3 concentration in the rat blood serum was registered in the oil-based vitamin D3 group on day 7—the tested vitamin concentration reached 198.93 ± 51.6 nmol/L. Comparing the duration of the effect of all vitamin vehicles, microencapsulated SmartHit IV™ supplementation vitamin D3 concentrations in the blood serum remained constant for the longest time (up to the 14th day).
Everything you put in your belly will show up in your blood at some point, quicksearcher. It doesn't mean it will be bioavailable for you in the right place.
Which is why the beaches & parks should be open to the public...
Edit: The down votes only supports what I have suspected, many on HN are authoritarian & should not be in positions of power. This is why many in the public don't trust you or your "Science", which are mainly buggy software models built on a tower of assumptions, enforced (ahem peer reviewed) by a priesthood of like-minded fools.
People do support empiricism & the humility of knowing there are unknown unknowns in any model
There are some good reasons that beaches and parks should be open to the public. There are also good reasons that beaches and parks should not be open to the public.
This study is not one of those reasons. The conclusion of this study is not one of those reasons.
The study recommends supplementation, which could come from sunlight & being outdoors, as sunlight increases vitamin d in the body. Getting out of the house by going to public parks or the beach is one way of getting sunlight & vitamin d...
The study is not remotely conclusive. The methods are indirect, the controls are weak, and the correlation model is misleading. Recommendations based on this study can and should be ignored, because this study doesn't prove anything. The only thing that should be done with this data, is using it to get funding for a better-designed study. To the credit of the scientists involved, I think that was probably their intent.
Yet we cite buggy & non-deterministic computer models to justify mass social & economic disruption. Funny these double standards...
I suppose, by your standards, that a healthy immune system is not yet "proven" to have any effect on Covid-19. Perhaps we don't have enough data to make a determination one way or another? Yet there's enough data to determine that we need heavy-handed government policy to lock everything down. Strange...
Think in terms of perception, possibility, & risk management. Here's one possibility. The usage of buggy, non stoichiometric, & non empirical models & questionable data collection led to the unstantiated fear mongering leading to the application of public policy which resulted in social & economic disruption. The politically connected benefited from policy while independent businesses were harmed.
Their claim of a very high p value and significant effect is VERY strongly influenced by a single outlier. It's not even close. On this unlabeled graph, I think x axis is vitamin D levels and y axis is deaths per million. They've got ~16 data points in the range of 0-10 deaths, one point at ~20, and one at 65. If you removed the 65 point the line would get a hell of a lot less convincing.