Security Now 209

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Security Now
Episode 209

Security Now 209: The Vitamin D Story

News & Errata

03:50 - 12:32

  • Apple have released updates for OS X and OS X Server
    • Security problems in the BZip 2 libary
    • A maliciously crafted website may control the displayed website URL in a certificate warning
    • A image could cause arbitrary code execution
    • Updates the list of potentially unsafe file types
    • A person with physical access to a locked system may use four-finger Multi-Touch gestures
    • Viewing a maliciously crafted Canon RAW image may lead to an unexpected application termination or arbitrary code execution
    • Viewing a maliciously crafted OpenEXR image may lead to an unexpected application termination or arbitrary code execution.
    • A format string issue in the login window may lead to an unexpected application termination or arbitrary code execution
    • Viewing a malicious crafted image may lead to an unexpected application termination or arbitrary code execution.
    • Processing a maliciously crafted PNG image may lead to an unexpected application termination or arbitrary code execution.
    • Processing a maliciously crafted PNG image may lead to an unexpected application termination or arbitrary code execution.
    • A logic issue exists in the MobileMe preference pane. Signing out of the preference pane does not delete all the credentials. So a person with access to the local user account could continue to access any other system associated with the MobileMe account which had previously been signed in for that account.
    • Receiving a maliciously crafted AppleTalk response packet may lead to arbitrary code execution with system privileges or an unexpected system shutdown due to a buffer overflow that exists in the kernel's handling of AppleTalk response packages.
    • Processing maliciously crafted XML content may lead to arbitrary code execution.

12:33 - 13:52

  • The Java runtime environment and the Java development kit have been updated

13:53 - 17:36

  • Microsoft released this months updates
    • Four critical vulnerabilities in Office Web Components that allow remote code execution using a specially crafted web page.
    • A vulnerability in Remote Desktop Connection
    • Two vulnerabilities could allow remote code execution if a user opened a specially crafted AVI file
    • Another fix for vulnerabilities in Microsoft's Active Template Library.

17:37 - 20:40

  • There is a common library flaw in the XML library that a huge number of open source utilities and systems are using.

20:41 - 22:34

  • There is a fake blue screen of death piece of scareware where it shows a blue screen and then pops up a message offering a fix

22:35 - 26:41

  • Twitter suffered DDOS attacks
  • Facebook, YouTube, and LiveJournal were also affected but not as badly
  • Initial reports were that it was a botnet attack but it is now thought that it was caused by users clicking links in spam

26:42 - 29:30

  • More than half of the top websites on the net are using flash cookies but only four sites mention the use of flash cookies in their privacy policies

Spinrite Story

No Spinrite story today as there is a lot Steve wants to talk about

Vitamin D

[Bracketed times refer to times on Steve's cut down version of the podcast]
33:20 - 01:42:00 [02:40 - 01:01:25]

[02:40 - 07:54]

  • Steve became interested in staying healthy when he saw older people at an airport struggling to move around
  • 3 months ago various mentions of Vitamin D began appearing (This would be around June based on the podcast recording date)

39:45 - 01:42:00 [07:55 - 11:47]

  • Vitamin D is not a vitamin it is actually a steroid hormone
  • A vitamin is something which you do not make endogenously, it's something that you must acquire through nutrition from outside sources
  • It was discovered due to a chronic deficiency in an unknown substance
  • As we became more industrialized and people moved from rural settings into cities, and especially as children were employed in buildings they began getting rickets, which is a severe underdevelopment of skeletal bones.
  • It was then discovered that taking cod liver oil cured this
  • It is the most powerful steroid hormone in the human body
  • The metabolic form is measured in picograms per milliliter
  • It is found in almost no food sources apart from fatty fish
  • We get it from the sun
  • The only place where it has received lots of attention, is in our body's calcium metabolism
  • You need Vitamin D and Calcium to build bone
  • Vitamin D is linked to Calcium mentablosim.
  • For thousands of years this is the only thing we knew it did

[11:48 - 15:08]

  • When we evolved from apes to humans we lost our fur to aid cool
  • When we lost fur in favour of skin we were being exposed to intense sunlight so we ended up developing a much more rich melanin content.
  • Melanin is the pigmentation in skin.
  • Ever since the beginning, we were also using sun (the ultraviolet radiation) for fundamental chemical reactions which take place in our skin.
  • A precursor of cholesterol called 7-dehydrocholesterol, or 7-DHC, that exists in our skin in abundance in youth, and we lose it as we get increasingly older.

  • The 7-dehydrocholesterol, when it is zapped by an ultraviolet photon, it is converted into an early form of what unfortunately we have labeled Vitamin D.
  • It's not stable in that form, and so it shortly changes its bonds around and just under thermal isomerization converts into something called cholecalciferol, which is the form of Vitamin D that you can also get in a supplement.
  • That's transported to our liver, where our liver changes it through a process known as hydroxylation into the Vitamin D which is measured in our bloodstream, something called 25-hydroxy Vitamin D. And that's sort of the bulk storage form of this chemical.

  • Our kidneys takes it the next step further, hydroxylates it again, and turns it into this super potent steroid hormone.
  • That's involved directly, it's that hormone which is involved with the regulation of calcium metabolism and our bones.
  • It turns out, though, that many other organ systems in our body also have the ability to deal directly with Vitamin D.

[15:09 - 19:23]

  • A nested, case-controlled study was conducted using subjects from the Johns Hopkins Operation CLUE Cohort. This cohort consisted of 25,620 health adult residents of Washington County, Maryland, who provided samples of serum between 1974 and 1975
  • Individuals whose 25-hydroxy Vitamin D levels were greater than 20 nanograms per milliliter had one third the risk of colon cancer

[19:24 - 22:12]

  • Talks about a study from the American Journal of Clinical Nutrition 2004,
  • Vitamin D deficiency has been associated with increased risks of deadly cancers, cardiovascular disease, multiple sclerosis, rheumatoid arthritis, and Type I diabetes mellitus.

[22:13 - 23:45]

  • Talks about "Prospective Study of Predictors of Vitamin D Status in Cancer Incidence and Mortality in Men"
  • Vitamin D levels have a direct influence on the chance of developing cancer

[23:46 - 25:32]

  • There's are studies which describe similarly that higher levels of Vitamin D are connected to lower levels of many different types of cancer - pancreatic, colon, rectal, stomach, prostate, lung, breast, bladder, uterine, esophageal, kidney and multiple myeloma
  • M.D. and psychiatrist at the Atascadero State Mental Hospital, John Cannell had his whole ward on Vitamin D for its psychological benefits
  • When a flu broke out in the hospital not one single patient in his ward on Vitamin D caught the flu

[25:33 - 29:08]

  • Autism is on the rise and his has been noted that the incidence of autism directly correlates with the latitude of the mother of autistic children during pregnancy. The further away mothers are from the equator, the greater incidence of autism in their children.
  • However it is important to note that correlation doesnt always equal causation and Steve uses this example to illustrate it:
  • Imagine that an alien came down, knew nothing about the way we operate and was watching a random street in New York, and noticed that suddenly everyone put their umbrellas up and, oh, look, then windshield wipers all began going on the cars.
  • Well, if you didn't know any better, you didn't understand anything about what was really going on, you could say that raising umbrellas caused windshield wipers to go on. Which isn't true.

[29:09 - 31:20]

  • You can not patent Vitamin D so there is no financial incentive to research it
  • There was a study between the years of 2000 and 2005 that took 1,179 women in Nebraska, which is at 41 degrees north latitude.
  • This was a double-blind, randomized, placebo-controlled study.
  • It divided the women in half. It gave half of them a placebo and calcium, and the other half 1,100 IU per day of Vitamin D and calcium.
  • If you ignore and throw out the first year of any cancers that were found, on the premise that those were already in the process of developing
  • During the rest of this study the women who were taking the Vitamin D plus calcium had 0.23 percent incidence of any type of cancer compared to the other half

[31:21 - 34:47]

  • Vitamin D can be toxic in very high doses
  • It is fat soluble, so it's not excreted from our body on an ongoing basis.
  • So like any fat-soluble vitamin, there's a concern that it will build up in your tissues over time.
  • Nobody has ever become Vitamin D toxic from sun exposure.
  • But it has been determined that half an hour in the sun will generate about 10,000 IU, 10,000 international units' worth of Vitamin D, which then over the course of a couple days enters your bloodstream.
  • Adequate levels of Vitamin D lowers blood pressure
  • There is a seasonal sine wave cycle of blood pressure
  • The extent, the amplitude of the sine wave varies with latitude, and it is synchronized to the calendar
  • It is well known that blood pressure goes down in the summer and goes up in the winter
  • People tend to get colds in the winter, and they get the 'flu in the winter
  • Maybe it's because our Vitamin D stores are depleted.

[34:38 - 35:45]

  • There was one study that attempted to demonstrate that watching too much television caused autism
  • The people who did the study didn't actually interview people for how much television they watched.
  • Instead they used the rainfall figures in the area.
  • What they were inadvertently doing was they were measuring probably the amount of sun that these kids were getting. And that's where the correlation was.

[35:46 - 39:47]

  • Nobody actually knows what the proper level of Vitamin D is
  • They set the RDA by measuring how much Vitamin D was in Cod Liver oil

[39:48 - 41:46]

  • There are three types of skin cancer; cell carcinoma, basal cell carcinoma, and malignant melanoma
  • Malignant melanoma is the cancer that everyone worries about
  • Interestingly, though, it generally appears on areas of the skin that are covered by clothing, probably because statistically most of us have more than the majority of our skin covered.
  • The squamous cell carcinoma and basal cell carcinoma is the kind that we see on our hands, arms, and face.
  • It's also the kind that your dermatologist can freeze off easily, and it's not a big deal as long as you've got someone looking at your skin from time to time, like your doctor takes a look at you to make sure that you don't have any of that.
  • What is believed is that, as we migrated away from the equator, because we are so dependent upon Vitamin D, that it became a powerful natural selection factor in our evolution.
  • As we left the equator and populations moved north up into Europe, we depigmented in something like several tens of thousands of years, maybe 50,000 years.
  • Because suddenly the high melanin content we had, which was protecting us from the sun at the equator, was also now blocking our ability to produce Vitamin D

[41:47 - 43:05]

  • We know when Vitamin D is really low that you develop chronic problems with calcium management and bone
  • Your body takes calcium from your bones to preferentially manage your blood calcium level because that's even more important
  • So your bones represent essentially a calcium repository that, if you don't have enough Vitamin D and/or calcium in your diet, there are mechanisms that'll pull calcium from your bones, which you don't want.
  • But now we're learning that it's very likely that this very powerful and necessary hormone has been incorporated into many other systems in our body.

[43:06 - 45:56]

  • There are Vitamin D analogs which the pharmaceutical companies are exploring
  • There are now some effective psoriasis medications which are all based on Vitamin D analogs

[45:57 - 55:59]

  • There is study after study that demonstrates that cancer, autism, allergies, diabetes, an amazing number of maladies have latitudinal correlations. And they've even noticed that even at a high latitude, if you're at a high altitude, then the incidences of these problems drop because you've got less atmosphere between you and the sun.
  • You also need to be in the sun when it is directly overhead any thing else wont have an effect
  • By the age of 50 our ability to produce Vitamin D endogenously in our skin, has fallen by half
  • By the age of 65 it's down to 25 percent of what it was
  • As you get older we lose the cholesterol in our skin
  • You get thin-skinned which is the result of a loss of cholesterol in our skin which reduces our ability to produce Vitamin D
  • The US government puts Vitamin D in milk

[56:00 - 58:44]

  • There are two types of D that you can purchase
  • There's D2, which is called ergocalciferol
  • Or D3, which is cholecalciferol
  • D3 is what we make
  • Cholecalciferol is the only kind you really want to take
  • It is essentially biologically identical to what we manufacture
  • There is some concern because it's made by irradiating the lanolin from lamb's wool
  • Ergocalciferol is made from irradiating fungus
  • So it's 100 percent plant based, but it's Vitamin D2
  • And some studies have said that it only raises your Vitamin D levels about 25 percent as high as D3
  • So D3, which is what we make when sun hits our skin, is substantially more effective than D2.
  • The only way the Eskimos were able to keep their relatively high level of pigmentation is eating oily fish.
  • They have a diet high in fish, and fish is the only source.
  • Three and a half ounces of salmon has about 380 IU of Vitamin D
  • And again, there are studies that have been done that estimate we use about 4,000 IU a day.
  • So you would need to be eating 35 ounces of salmon a day, which you might get tired of after a few days.

[58:40 - 01:00:40]

  • Cod liver oil is really not the best source it does give you Vitamin D
  • But it also contains the other fat soluble vitamin, Vitamin A
  • And a lot of Vitamin A can be a problem.
  • And also Vitamin A genetically looks very much like Vitamin D, and there have been reports that say that A can block the positive effects of Vitamin D
  • So getting A in the form of beta-carotene is really what you want because your body is able to convert as much as it needs over to A.


Go To Assist Express

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Production Information

  • Recorded Date: August 12, 2009
  • Release Date: August 13, 2009
  • Duration: 1:43:42
  • Log line:
  • Edited by: Tony
  • Notes:
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