Is Vitamin D the "Missing Link" of Flu Prevention?

Vitamin D and Flu Prevention: Part 1

Influenza (the flu) is the poster-child of seasonal variability in an infectious disease. During "flu season" rates of influenza skyrocket, but in the warm, summer months the virus is seemingly dormant. I think that last bit does a particularly good job of beginning to elude to the commonly held beliefs surrounding the flu. Public officials tell us every year that this is going to be a bad year for the flu- perhaps the worst one yet. I think that most people conjure up an image of a virus that "attacks" every year, is defeated (fails to infect everyone), goes into hiding for the summer and makes itself bigger and better, and mounts an attack again the following year. It seems simple enough why people get sick- if you come into contact with enough germy people and if the virus is "bad" enough the virus will get you; it's only a matter of time. But what if the virus isn't the biggest variable in this equation- what if it's us?

There is a number of theories for what makes us more susceptible to infection in the winter. The start and end of the school year, the fall of absolute humidity in the winter months which dries out mucous membranes, seasonal patterns of behavior, temperature fluctuations, changes in viral transferability, and changes in host (human) immune function throughout the year all almost certainly play some role in influenza transmission [2]. Out of all of those reasons, however, one theory has risen above the rest in terms of answering unanswered questions (below) and promising research trials (to be discussed in Part 2).

Host (human) immune function is dependent on Vitamin D

Vitamin D is considered to be a hormone- a chemical that is made in one cell or gland (skin cells), released into the blood stream, and affects other cells in the body. Vitamin D is known to regulate at least 913 genes [3], including many that regulate immune function. Vitamin D is the major regulator of several antimicrobial peptides (AMPs) (you're body's in-house, broad spectrum antibiotics), namely cathelicidin and beta-defensin [3,4]. Among other functions, AMPs are known to protect the body's barrier surfaces (lungs, mouth and throat, gut) by creating a hostile antimicrobial shield [5]. This alone has tremendous implications in disease transferability! If the virus can not get past these barriers and get into the body it makes it tremendously difficult for it to make you sick. Vitamin D is also a key player in the innate immune system [3,5], which is the body's first, non-specific line of defense against pathogens. One way it does this is by enhancing TH3 cell function- T Helper cells that keep the rest of the immune system running smoothly. Fascinatingly, new research has shown that cells of the immune system and epithelium (barriers) are able to convert the non-active form of vitamin D into it's active metabolite [6]. This mechanism may further demonstrate the immune system's dependance on this modest little hormone.

Vitamin D as the "seasonal stimulus" answers many otherwise unanswerable questions about Influenza's odd behavior [5]

1. Why is Influenza both seasonal and ubiquitous (everywhere) and where is the virus between epidemics?
It is unlikely that the virus hides each summer and magically comes out in the winter. What's more likely is that the virus is around us (and in us) all year-round, but during times of enhanced immunity (sun exposure) we are able to fight it and remain asymptomatic.

2. Why are the epidemics so explosive?
As vitamin D levels begin to drop in the fall and winter months, so does our ability to fight infections. After a prolonged amount of time without sun exposure people's vitamin D levels will begin to fall, resulting in more and more people becoming increasingly more prone to infection. Once people's vitamin D levels drop below their tolerable threshold (which is most likely different from person to person), a subset of the population would find themselves suddenly susceptible to infection.

3. Why do epidemics end so abruptly?
It is likely that there is a sub-population of "good transmitters" within each population, which may be associated with each person's degree of Vitamin D deficiency. The depletion of this limited supply of good hosts most likely plays a large role in flu season's speedy resolution.

4. What explains the frequent coincidental timing of epidemics in countries with similar latitudes [5]? Why is the seasonal pattern of Influenza so weak or non-existent in equatorial regions [1]?
The peak of the last 25 epidemics in France and the USA occurred within a mean of four days of each other [5]. Similar latitudes likely follow a similar pattern (in both severity and seasonality) of impairments in innate immunity. This would also explain why regions closest to the equator experience fewer cases of influenza and seem to exhibit no pattern of seasonality [1].

5. Why is the serial interval so obscure?
The "serial interval" refers to the amount of time it takes for an infected person to make a well person sick. The serial interval has been shown for a number of other respiratory diseases, but has yet to be established for Influenza [5]. It appears that the presence of "good transmitters" among a population, who's infectious period is limited, makes this incredibly hard to measure for Influenza. The variation in Vitamin D status from one individual to another is likely one of many factors that seperates the "good transmitters" from the poor transmitters.

6. Why is the secondary attack rate so low?
For a  (supposedly) "highly contagious" virus such as Influenza, it's secondary attack rate is surprisingly low- about 15-20% at most, compared to 70% for measles and 58% for rhinovirus [5]. This is inconsistent with the idea that the virus sustains itself via regular sick-to-well transmission. The presence of a limited number of "good transmitters" as a result of vitamin D variation likely plays a role. Surely we've all known a person who always gets sick when there's a bug going around? It would be interesting to measure that person's vitamin D levels!

7. Why did epidemics in previous ages spread so rapidly, despite the lack of modern transportation?
"If Influenza were embedded in the population, only to erupt when impairments in innate immunity create a susceptible subpopulation, the disease would only give the appearance of spreading. Instead, it would appear in large segments of the population seasonally, and almost simultaneously, as long as good transmitters were available" [5].

8. Why are so few sickened by direct aerosol inoculation of influenza virus?
If the virus is highly infectious, one would expect most, if not all, people to fall ill when exposed to the virus. However, this is not the case. Even if the virus is sprayed directly into patient's eyes, nose and throat (I swear they really did this in 1918 and 1919) none of the volunteers became ill in any way. Other studies found similar results, where none or relatively few of the volunteers became sick after direct exposure to the virus. Once again, we must ask ourselves what makes one person susceptible and one person all but impervious to infection?

9. Why have influenza-related mortality and hospitalization rates significantly increased in the last three decades, despite profound increases in the rate of influenza vaccination?
Simply said, because vaccine manufacturers and researchers grossly overestimate the effectiveness of the flu vaccine every year. The flu vaccine lowers the incidence of the flu by 1.55%. If you want to know why I am so certain in saying so, please check out my previous blog posts on the flu vaccine here.

Check back soon for Part 2 of this series- I will be going over the current research on vitamin D as a means of preventing the flu.


Stay healthy out there, folks!

References:
[1] Juzeniene, Asta et al "The seasonality of pandemic and non-pandemic influenzas: the role of solar radiation and vitamin D" 2010 [PMID 21036090]
[2] Shaman, Jeffrey et al "Shortcomings of vitamin D-based model simulations of seasonal influenza" 2011 [PMID 3108988]
[3] Lang, PO "How important is vitamin D in preventing infections?" 2012 [PMID 23160915]
[4] Aranow, Cynthia et al "Vitamin D and the immune system" 2011 [PMID 3166406]
[5] Cannell, John et al "On the epidemiology of influenza" 2008 [PMID 2279112]
[6] Sundaram, Maria et al "Vitamin D and influenza" 2012 [PMID 3649720]

Beware of Junk Science

The more I learn about health, the more I realize being healthy should be a no-brainer. Eat more vegetables. Move more. Laugh more. Put down that PopTart. But what about all the scads of conflicting information out there? Low fat, low carb, or low cal? Which of the thousands of antioxidants available should we be taking? Fish oils, resvertrol, goji berries, green tea? Is sunlight good because of the vitamin D, or bad because it increases our odds of skin cancer? Should we eat that egg yolk?

In many cases false information is propagated by one thing- money. I'm not saying that everyone with something to sell is trying to dupe you out of your money... I'm just saying they have something to sell you. As long as we remain objective and never stop asking questions, we will get along just fine in this free market economy, but it's always nice to have a little help to weed through information. Junk science is science (or something that seems scientific) that is produced or interpreted by those with special interests. For example, articles investigating the safety or efficacy of a drug that are being funded by the company that makes said drug. Can you say "conflict of interest"?

But I digress.

There is one particular experiment I have seen recently in the media and on the internet that I just couldn't resist debunking. On websites such as this one, authors say that you can test your vitamins by seeing whether or not they dissolve in water. While I will be the first to admit that most multivitamins sold in the stores are not only junk, but might actually be harming you [1], this is not a valid test by any means.

My favorite example of this lately is this popular commercial for a CoQ10 supplement, Qunol. The makers of this supplement boast that their product dissolves better in water than other CoQ10 supplements... but when did we decide that this was a good thing? Beyond the issues I outline below, CoQ10 is a fat soluble antioxidant, which means it should NOT be able to dissolve in water. The makers of this product are bragging about a quality in their product that is actually undesirable! That's marketing for you.

There is SO much more going on inside your body than in a cup of water it's exhausting to imagine listing them all, but for the sake of the article I will talk about just a few.

1. Stomach acid is extremely acidic- ranging in pH from 1.5 to 3.0 [2]. As we all know, acidic is extremely corrosive- apparently enough so to dissolve razor blades [4]! I should hope such a strong acid would be able to dissolve a pesky pill or two. While the above article did state that vinegar better mimics the stomach's acidic environment than water, vinegar is only moderately acidic with a pH of 4.25-5.0 [3]. Compared to the stomach's pH of about 2, even at it's strongest (we'll say 4.0) vinegar is 100 times weaker than stomach acid.

2. There's more stuff in the stomach than just acid. Even if you did dunk those pills in a vat of acid that is the same strength of stomach acid, you still couldn't hope to make up for all the other stuff in our guts. Digestive enzymes such as salivary amylase start working on your food the moment it enters your mouth and continually get added throughout the digestive process. Amylases, proteases, lipases, pepsinogen, intrinsic factor, mucous, bile salts, bicarbonate, and a plethora of gastric hormones are among the many, many things that get secreted as food moves through the digestive tract.

3. The digestive tract is a muscular tube. The juices that digest our food only make up a part of the whole digestive picture. The stomach is a big muscular bag and the rest of the digestive tract is one long muscular tube that is constantly pulling, pushing, squishing and mashing the ever-loving heck out of the food we eat. Last I checked, cups of water weren't capable of such things... even with the most vigorous of stirring.


The question we should be asking ourselves is not weather our pills can dissolve in a cup of water. Rather, once the pill (or food) is broken down will it be absorbed from the digestive tract and properly used in our body? If there is a leaky gut or inflammation afoot I would say the answer to both of those questions is a "no".

Take care and beware of junk science, dear readers


Nikki Cyr, D.C.


Resources
[1] http://createanewbox.blogspot.com/2012/11/metals-that-might-make-you-mental.html
[2] http://en.wikipedia.org/wiki/Gastric_acid
[3] http://en.wikipedia.org/wiki/Vinegar
[4] http://www.mnn.com/health/fitness-well-being/stories/infographic-28-odd-facts-about-the-human-body
[5] http://www.ehow.com/how_5641704_test-vitamins-home-dissolving-water.html

Iron Deficiency Anemia

Anemia is a relatively common condition in which the blood's Oxygen carrying capacity has been compromised. This may be due to a loss of red blood cells, low Iron or hemoglobin, lack of B vitamins, or misshapen red blood cells as is seen in Sickle Cell Anemia.

The most common form of anemia both worldwide and in the United States is Iron deficiency anemia (IDA). Commonly seen in women, particularly those whom are pregnant, have a heavy menstrual period or are vegetarians, IDA is easily corrected by increasing your consumption of Iron. This is usually accomplished by taking a prescription Iron pill that I have nicknamed the Home Depot Special. I mean, have you ever cut one of those things open? It looks like someone took a chunk of Iron ore from the Home Depot, made it into a pill, and painted it red.

IDA seems like a simple enough condition with an even simpler cure: Take Iron. But after our last blog post where we discuss just how toxic inorganic Iron can be to the human body, it may leave our anemic readers a bit confused. On the one hand, you don't want to be anemic- without proper oxygenation of your tissues your body will be less able to build and repair itself and it will leave you feeling worn down. On the other hand, being the well-read, informed patient that you are, you probably don't want to take the Home Depot Special pills, either.

First we must ask the question, why is your Iron low in the first place? The many different causes of IDA require completely different treatments.

1. You lose a lot of blood. This is generally seen on a CBC as a high RDW value (above 15 on most labs). Perhaps you have a heavy menstral period because of a hormonal imbalance or PCOS, in which case addressing those conditions would correct the problem. Perhaps you have an internal bleed such as an ulcer, which would require a completely different work up and treatment than the above.

2. You don't eat enough Iron. Most people will tell you that this is seen in vegeterians, but I have found that vegan and vegeterian eaters can get along quite alright without extra protein and Iron. In my experience, this is more often due to just plain old unhealthy eating habits. There's not a whole lot of nutrients in Doritos last time I checked, guys. Stop fooling yourselves and eating that garbage.

3. You're not absorbing the Iron you are taking in. Honestly, I think this is by far the most common (perhaps in combination with number 2) reason people develop IDA. The big thing you need to know is that you need two things to digest and absorb Iron: Stomach acid (to break it down) and a healthy intestinal tract (to bring it into the body).

Low stomach acid, or hypochlorhydria, can be caused by a myriad of things including infection by a bacteria called H Pylori, or drugs that decrease stomach acid. For example, proton pump inhibitors (Prilosec, Omprezole) decrease the stomach cells' ability to make stomach acid. These drugs are used to treat ulcers, but all too often patients are left on these drugs for years after the ulcer has healed. Likewise, acid blockers such as Zantac and Pepsid have become increasingly popular and are often taken on a long term basis. These drugs are often advertised with the implication that you can now eat whatever you want without all those pesky unpleasant symptoms. I guess they forgot to mention the fact that those symptoms are just your body screaming please don't do this to me.. For Pete's sake put down the hot dog!!

Altering the state of the stomach's acidity not only leaves you vulnerable to nutrient deficiencies such as IDA, but it leaves the GI tract vulnerable to infection by opportunistic bugs like H Pylori. Because these drugs drastically alter your ability to digest your food properly (especially protein), food transit time through the stomach slows, allowing food to sit in the stomach for long periods of time and fester. This putrid food hanging out in the stomach longer than it's supposed to may produce symptoms of indigestion. Wait, wasn't that what we were trying to avoid in the first place?

Many, many things can cause malabsorption at the small intestine level. Celiac Disease, Crohn's Disease, Ulcerative Colitis, and Leaky Gut Syndrome have all been known to cause multiple nutrient deficiencies, and as you can imagine, their treatment involves far more than one little Iron pill. Another increasingly common reason for malabsorption in this country is due to malabsorptive surgery such as the gastric bypass. There are several various flavors of bariatric surgery, and they all have slightly different effects on the GI tract. For example, the gastric bypass mostly alters the stomach size, and therefore has the greatest impact on one's acid producing equipment. The Roux-en Y Gastric Bypass, on the other hand, is a procedure in which they actually bypass the first part of the small intestine all together. This sets the stage for great potential weight loss, but also for great potential nutritional consequences. Since about 90% of the vitamins and minerals in food are typically absorbed in that first, short portion of the small intestine, bypassing it severely handicaps that GI system for the rest of that persons life.

So what can we do to try to correct IDA without taking the Home Depot Special pills?

1. Stop to think, why am I anemic in the first place? Yes, getting to the root of the problem might be harder than simply popping a pill for the rest of your life, but it will be worth it. Really.

2. Stop with the acid blockers already! If this means going off a prescription medication communicate with your doctor, but be aware that they might think you've lost your mind. Your doctor should know that these medications were never meant for long term use, but if they give you a hard time just stick to your guns and explain why you are concerned.

3. Eat food that actually contains Iron. I know, it's a wild concept. And no, this does not mean that Iron fortified cereal is now a health food. I'm talking about real food that has real Iron- healthy meats, spinach, kale, chard and other green leafy veggies.

4. Even after all that if you are still Iron deficient (perhaps due to pregnancy), find a source of Iron supplementation that didn't come from a hardware store. I don't know of one off hand that is commercially available, but if you talk to someone in the supplement section of a Sprouts or a Whole Foods they should be able to help you. Functional medicine doctors such as myself often carry good quality Iron supplements in their office, but these products will only be available through the doctor's office.

Happy to be out of their box,

Nikki

A Note on Choosing Supplements

I recently went to a health talk that my supervising doctor put on at Arizona State University, and one of the attendees brought up this great question. How do you find good quality supplements? I mean, if you walk into a Whole Foods or a Sprouts these days it's like the bread isle on crack. There's 8,000 companies offering 9,000 products, all the while claiming that theirs is the best. But how do you know you're getting what you paid for? Or more importantly, how do you know if you're paying for something you really didn't want?

Functional Medicine practitioners such as myself work with pharmaceutical grade supplements from many different companies. Such companies only sell their products to licensed healthcare professionals. To you out there in the world who just wants some vitamins this may be annoying, but believe me when I tell you it is for your own good. When they say pharmaceutical grade they really mean it... which means two things. On the one hand, you can have a great therapeutic (positive) effect with these supplements. On the other hand, you can do a lot of damage with them if you take them inappropriately... I know- I've made myself sick stimulating the wrong pathway a time or two and I've heard friends' stories after they've done the same. If these products got into the hands of the general public who doesn't know how to use them properly a lot of people would be in a whole world of hurt. I'm not saying that non-pharmaceutical grade supplements aren't effective... Just perhaps not as effective as what we in FM use. The other plus side to going to a doctor for your supplements is that they will run tests (blood, urine, saliva) to ensure that you are taking the right thing.

For those of you who don't want to go to a doctor, there is a more reasonable way to find good quality supplements. Consumer labs is a third party company that tests and reviews different supplements. There is a small subscription fee that goes toward funding the tests that they run, and it is well worth the fee. Not only do they test the supplements for what they claim to contain, but they test for contaminants. For example, their review of vitamin D supplements revealed two products that were contaminated with Lead [1]!

Stay healthy,

Nikki


References:
[1] https://www.consumerlab.com/reviews/vitamin-d-supplements-review/vitamin_d/