Iron- good for more than just pumping!

 Did you know that iron deficiency is the biggest cause of anemia worldwide? Anemia, for those unfamiliar, is when your blood isn't able to carry enough oxygen to your body, either due to a lack of red blood cells or lack of iron. How does iron figure in? Let's take a little journey inside your red blood cells to find out.

Google a picture of a red blood cell. What you'll see is a bi-concave disc (meaning it's a frisbee with a dimple on either side) that is, as the name implies, red. While you might think the shape is just for kicks, it actually serves a very important function. It's hard to imagine but your tiniest blood vessels are only wide enough for a single red blood cell (let's call them RBCs) to fit through, and it's often a very tight fit! What being bi-concave means is that your RBC is able to bend and flex around tight corners and through tiny blood vessel tubes. There are some folks who have certain blood diseases where their RBCs aren't this fabulous shape, they are spheres (hereditary spherocytosis) or shaped like crescent moons (sickle cell anemia), and those folks can have all sorts of problems, just from the shape! With spherocytosis the cells are very fragile and prone to burst open when put under pressure. In sickle cell anemia the funky shape means that the RBCs tend to get stuck and pile up in those narrowest of blood vessels. So be thankful if you are in that lucky majority who have normal shaped RBCs.

Now let's go inside the RBC. Really, in comparison to most of your cells, there's not a whole lot. There's no nucleus, which is the middle "yolk" of the cell that has all that important stuff like DNA. RBC are one a few types of cells in your body that don't have a nucleus, mainly because when they die, new cells get made from scratch rather than divide and have children cells, so they don't need DNA. What RBCs are packed full of is a molecule called hemoglobin. Hemoglobin is this fancy little protein that is made of two pairs of identical globs of protein (picture four snowballs in a square). In the center of each of these globs is a molecule that kind of resembles a trampoline, called heme, and in the middle of the trampoline is one single molecule of iron suspended. Since there are four snowballs in each hemoglobin that means that there are four iron molecules too, which doesn't seem like much, until you consider that every single RBC has an average of 280 million molecules of hemoglobin! That means there are four times that amount (I'll let you do that calculation) of iron in every RBC! Then, when you consider that the average adult has 20-30 trillion red blood cells, that gets to be a lot of iron!

So why iron? Iron has this nifty ability to bind easily to certain types of molecules, which includes oxygen (think about that old piece of rusty metal- that's iron binding oxygen too!). When a red blood cell gets into the blood vessels in your lungs it comes in contact with oxygen and the oxygen sticks to the iron molecule like a magnet. Then when that same RBC gets out to your foot which needs oxygen the iron kicks the oxygen off, then returns to the lungs to do it all over again. Unfortunately, other things can also bind to the iron. Things like carbon monoxide which binds even tighter than oxygen. Hence why carbon monoxide is so deadly toxic to you. It binds to your iron and doesn't let go easily, thus depriving your tissues of the oxygen they need to function. You will also get symptoms of this lack of oxygen if you don't have enough iron to carry the oxygen, this is called iron deficiency anemia. You can get anemia from a lot of different reasons, but this is by far the most common cause. It is most common in children and elderly folks, who are less likely to eat iron rich foods like meat. In many developing countries iron deficiency anemia is very common, especially in urban areas where poor families have little access to affordable meat. In India the rate among children is currently estimated to be around 80%. Some of the consequences are stunted growth, poor immune function, and general weakness and fatigue, among others.

There are also many interfering factors which can contribute to iron deficiency. For example calcium interferes with your body's ability to absorb iron. One recent study suggested that the ideal amount of milk for children to consume was no more than two cups a day. Any more than that could put them at risk of becoming iron deficient due to the amount of calcium in the milk. Another major interfering factor are molecules called phytates. These are found in grains and can also prevent your body from absorbing iron from the meal. An easy way to remedy this is to soak the grains overnight before using them, as this breaks down the phytates. For example, my little man loves oatmeal in the morning so I set out the bowel of oats in water with a little yogurt and let it sit overnight before cooking in the morning. This breaks down the phytates as well as starts a slow fermentation (from the yogurt) which makes the grains much easier to digest. Most traditional societies who eat grain would often do some sort of fermentation before consuming them, inherently recognizing that this made the nutrition in the grains much more accessible. Lead poisoning can also mimic iron deficiency anemia, but research suggests that it's due to the lead getting in to your bones and messing up the production of red blood cells as well as the lead interfering with iron being attached to the hemoglobin. Lead has largely been removed from modern homes, but in older homes it can still be found in paint and pipes. I know in Portland you can request a free lead water test if you live in an older home and have a child under 6 or a pregnant woman living in the home. If you are concerned about your water or paint it doesn't hurt to look into testing as even tiny amounts of lead can have pretty significant effects.

Then there's the issue of vegetarian supplied iron vs. iron from meat. You have probably heard that spinach and other dark leafy greens are just teeming with iron along with all sorts of other good vitamins. Well, it's true, but unfortunately your body has a much harder time absorbing iron from non-meat sources (this is considered "non-heme" iron vs "heme" iron that comes from meat). The iron must go through a series of reactions in your gut before it can be absorbed through the intestines whereas iron that is coming from meat is already in the proper form to be able to be sucked right up in your gut. There are a few things you can do to increase the amount of iron you absorb from food. The main thing is vitamin C. Having a big glass of orange juice or including other vitamin C rich foods with the meal can really help your body absorb more iron. Oh, and in case you're wondering, cooking in cast iron pans has also been shown to be a small source of iron for those who are just slightly deficient as trace amounts of the iron get into the food as it cooks.

So, how much iron do you need? Well this answer is different for everyone (of course- in naturopathic medicine we always approach every person as an individual), but there are some general guidelines that can help. When in doubt, it never hurts to get your iron levels checked by a medical professional, especially if you are experiencing any of the signs of anemia. Your body is actually incredibly efficient at recycling iron. When your RBCs gets broken down very little of the iron is actually lost. This means that for healthy men and non-menstruating/non-prego/non-lactating women the daily iron requirement is much lower compared to menstruating women or anyone suffering from blood loss. Children have their own requirements as they are (obviously) growing and increasing their blood supply daily. The National Institute of Health has put together several tables of daily requirements as well as recommendations on good sources of food iron: http://ods.od.nih.gov/factsheets/Iron-HealthProfessional/ I hope you feel much more informed about iron, but truly this just scratches the surface. The link above has a lot more information and resources if you want to learn even more!

Why Vitamin D is so good for me!

For the better half of the last century we have been told that the sun is our enemy. It gives us skin cancer and that the smartest thing we could do was slather on thick layers of sunscreen, wear a hat, and avoid sunburn. Unfortunately, as often happens in our society, the pendulum now seems to have swung too far. Research definitely tells us that sunburn is a bad bad thing. Even just one severe sunburn in childhood can raise your risks of developing skin cancer as an adult by a significant amount. But in our "go big or go home" rush to avoid the sun we have inadvertently caused most of us to become vitamin D deficient.

You have probably heard that we get vitamin D from the sun. Actually, it's a little more complicated than that. Vitamin D starts as a molecule called 7-dehydrocholesterol (yes, it's based on that same cholesterol you hear all the hype about). When 7-dehydrocholesterol gets into the blood vessels just under your skin, and you happen to be out in the sun, the UV rays trigger a reaction to produce cholecalciferol (coal-aay-cal-sif-fur-awl). This reaction takes about 10 minutes to really get underway and a whole day's worth of vitamin D can be produced in about 15-20 minutes of moderate sun exposure (this rate varies based on skin type- faster for lighter skin, longer for darker), but after too long in the sun your body does a very smart thing. Vitamin D in high doses can be toxic so your body naturally starts limiting the reaction. This means that more than 20 minutes is no longer beneficial in raising your vitamin levels and can actually start destroying more than is being made. When you get tan you make this reaction take longer by absorbing more of the light in higher layers of your skin with the pigment melanin. So tanning (among other things) is your body's natural way of protecting you from too much vitamin D if you are someone who spends a lot of time in the sun. For most of us in the US it would be easy to get our daily allotment of Vitamin D from the sun during the summer, but in the winter things get a little more tricky. Not only are the days super short, but if you live above about the 30th parallel (which includes most of the US except Southern Florida and Hawaii) the sun doesn't even get high enough in the sky during the winter to penetrate the atmosphere with enough strength to trigger the reaction in the skin. So even if you live in a sunny area and get out there naked in the freezing cold you sadly won't be producing enough Vitamin D to qualify for a day's allotment.

So back to our story of how your body actually makes Vitamin D. After the sun hits your skin and makes cholecalciferol it then travels to your liver where another reaction happens which changes it ever so slightly into a molecule called (boringly) 25-hydroxycholecalciferol. This then goes to the kidney where it undergoes yet another change to become 1,25-dihydroxycholecalciferol. Woohoo! We made it to the active form of the vitamin! This form only lasts approximately 2-4 hours in circulation before it begins to break down and you have to start the process all over. As you can imagine, with this kind of complicated path there are a whole host of things that can go wrong! So besides not getting enough sun, people can be low on vitamin D if they are missing any of the pieces of this puzzle.

The primary function that has been conventionally assigned to vitamin D is in bone formation. You need proper amounts of Vitamin D in order to even absorb, let alone use calcium and all the other fabulous bone building minerals. Vitamin D actually turns on a gene which makes protein in your gut that binds to calcium to allow your body to absorb it. Vitamin D has also been shown to protect against cavities (for some of the same great reasons why it's so good for your bones). In fact, in one study looking at over 3000 children from 1920-1980 researchers found a 50% reduction in cavities in the kids with adequate Vitamin D.

For thousands of years people in colder latitudes have eaten traditional foods that supply Vitamin D during the cold winter months. Vitamin D is a fat soluble vitamin which means.... surprise... that you find it in fats! Cod liver oil, lard, whale fat, dairy, meat (not lean and  often organ in nature) all these yummy (?) favorites are great traditional sources of Vitamin D. If you've read my fats blog then you'll know how fabulous fat soluble vitamins are, and Vitamin D is no exception! Among other things it acts as an anti-oxidant (yes, just like blueberries) and helps to protect your tissues from those nasty free radicals. It is also considered a  "prohormone" which then gets converted into... you guessed it.. a hormone! Researchers have found vitamin D receptors on virtually all of the body's cells. You wouldn't expect to see that many receptors if it wasn't a pretty important thing! You don't have to look far to see what happens when your body lacks Vitamin D. The disease rickets, where your bones fail to form normally, is the manifestation of a severe Vitamin D deficiency, but Vitamin D deficiency has been associated with a host of other diseases like multiple sclerosis (MS), diabetes type I (the autoimmune version), and the biggie: cancer. Not surprisingly, 84% of patients who go to the Cancer Treatment Centers of America are deficient in Vitamin D.

Like I said above, we know that severe sunburn can increase your risk of skin cancer. In fact, sun exposure in general increases your risk of skin cancer simply because those same UV rays that convert the vitamin D also can hit things like your DNA and trigger mutations which then lead to cancer. However, medicine is now starting to find out how much protection the sun gives us from cancer via..... Vitamin D! Among the cancers that Vitamin D has been shown to protect against: breast, prostate, ovarian, colon... the list goes on.... and these are not minor cancers! These are the biggies that require intense treatment and often come back again and again. Skin cancer, on the other hand is easily treated by removal (duh, skin is a lot easier to reach than your ovary) and is much more sensitive to conventional cancer treatments (you can see it, therefore radiation can too). Plus you can easily observer skin cancer and therefore it is much more frequently found in routine screenings or by the person themselves and is caught at earlier stages (which means it's easier to treat). These differences in cancer types and treatability are significant and have everything to do with figuring out the cost-benefit ratio for sun exposure. One recent study concluded that the protection that Vitamin D gave against some of those nasty internal cancers listed above far outweighed the related increased risk of skin cancer from moderate sun exposure (not counting those nasty burns)! Let me say that again because I know it took me re-reading it a few times before it sunk in. With moderate sun exposure, your risks of all sorts of nasty internal cancers goes way down and your risk of skin cancer only rises slightly. Wow! Ahhhh... this is making me crave a little sunshine... too bad it's midnight in Portland!

So how does Vitamin D do all this cancer magic? Does anyone know? Yes! There have been multiple studies looking at the so called "mechanism of action" of this fabulous vitamin and it largely has to do with it's hormonal function (remember I told you it was a hormone). Not only does it turn on the genes that cancer turns off (mainly those that stop the cell from self-destructing when it realizes things have gone awry), it also turns on anti-cancer genes (specifically one called p53). Vitamin D also helps to keep your whole cell cycle functioning properly. This is the grow-->divide-->grow-->divide....die cycle of your cells. If this malfunctions and things start to grow, and grow, and GROW you get tumors, so keeping the cycle turning properly is very important. Vitamin D also has that great little quality of being an antioxidant like I mentioned above and helps to knock out nasty free-radicals in fatty tissues. Despite your thoughts about your belly fat not mattering if the free radicals invade, you do actually have some very important fatty tissue like the insulation around your nerves (called a myelin sheath), oh... and this little old thing called your brain! If free radicals get out of control (you mean get radical?) they can cause widespread destruction of your DNA which... you guessed it, leads to cancer! So keeping them in check is definitely a good idea.

Oh yeah! Vitamin D also helps to regulate the production of a protein in your body called cathelicidin. This protein is part of your body's innate immune system which is the first part of your immune system to get activated any time you have an infection. It helps to "nip it in the bud" as they say. Having adequate Vitamin D helps ensure that your body is ready and armed to fight the bugs, be they bacteria or be they viral.

So, in summary: Vitamin D is made beginning with a reaction triggered by the sun. It is naturally found in fat (and is commonly supplemented into dairy and other foods) and meat to some degree. It has some very important functions in your body (remember the receptor is found on virtually every cell in your body!) and protects you against all sorts of nasty cancers, autoimmune diseases, helps support your bones and teeth, and helps your immune system be ready to fight. You cannot get adequate vitamin D in the winter months in the US (unless you live in Florida or Hawaii- call me I need a sunny vacation!) and supplementation is generally recommended (always good to get your values checked to see how much is needed). The current recommended daily allowance was raised in 2010 to 600 IU for pretty much everyone (special rates for those under 1 and over 70). Since it's winter up here in Oregon and trying to snow I will be including my vitamin D in my regimen today and every day until the sun comes back in the spring.... ahhh.... daydreams of sun.... and Vitamin D!

One last note! I forgot to talk about D2 vs D3. Vitamin D2 is a molecule called ergocholecalciferol which your body can then convert into cholecalciferol, but only does so at about 33% efficiency, so it's considered 1/3 as bioactive as D3 which is straight cholecalciferol ready to go to your liver. D2 is often the form that will be naturally occurring in dairy products as it is made when hay is left to dry in the sun, then the cows eat the hay, and magic! Vitamin D enhanced dairy! The downside, other than the poor bioavailability is that it is much easier to build up toxic levels of supplemented vitamin D2, hence why you rarely see it marketed as a supplement any more.

Here are a couple references from which I pulled some of this information:

The Huffington Post (huffingtonpost.com) - Vitamin D Might Protect Against Tooth Decay: Study -By Annie Hauser - (Friday, December 07, 2012) -

The Wall Street Journal (wsj.com) - Multiple Sclerosis Linked to Vitamin D Levels, Study Says -By Jennifer Corbett Dooren - (Monday, November 19, 2012)

Vit. D and Diabetes type I

http://well.blogs.nytimes.com/2012/11/26/low-vitamin-d-level-tied-to-type-1-diabetes/?partner=rss&emc=rss

Vitamin D and Cancer

http://www.pnas.org/content/109/46/18827.full?sid=92caf2e8-8f44-4550-be05-447b52d9dd09

I also included information I learned last summer in my Integrative Oncology Research Course and the basic biochem came right out of my biochem lecture on Vitamins from last year.