Warning: This contains spoilers, including some for the main plot points of the movie "World War Z". Read on only if you've seen the movie, don't plan on seeing the movie, or really, really like spoilers. 

Tonight I took my wife to see the movie World War Z. She doesn't often go to movies with me. In fact, she doesn't even really like seeing movies in the theatre at all. But, for a zombie movie, she was easy to convince.

My thoughts on the film? I really liked it. I thought there was a good balance of action and suspense. I don't care that the characters were underdeveloped and I didn't mind that the movie had almost nothing to do with the book it was "based on". I wanted a fun, suspenseful zombie flick and I got it. There were a few things that bothered me, though, and of course they were science related. I can't help it - when a major plot point requires science I spend more time analyzing the science than enjoying the movie. I was able to shut off my brain for most of the film, but here's a few things that bothered me.

#1 - The Virologist
There is only one hope for humanity - a young virologist who knows everything about how to fight the zombie virus.

Why it bothered me
I was really worried when I saw this virologist character enter the picture. He's a young, brilliant scientist who is presumably humanity's last chance to find a cure. The reason this bothered me is that science really doesn't work like that - it's not a solo endeavor and there's not one person without whom we would be completely lost. True, there are some great scientists who have contributed enormous amounts of knowledge, but a major field doesn't usually just die because one researcher isn't researching anymore. Science is extremely collaborative - even if you're doing research on your own. There are papers, conferences, and discussion. Science doesn't move forward on the shoulders of one person. The "savior" scientist character is a little annoying, so I'm glad they took him out (or rather, I'm glad he took himself out).

#2 - The Virus That Knows You're Terminally Ill
Our protagonist notices that the zombies don't attack the weak or terminally ill. We learn that the virus will only seek out a healthy host.

Why it bothered me
I could actually believe the science of this . . . almost. It makes sense though, from an evolutionary standpoint, that the virus would be "programmed" to seek the next step in its life cycle - in this case a healthy human. It's even true that, as one scientist in the movie said, "there is a precedence for this kind of behavior." It's just a case of mind controlling parasites, which I've written on before.

The problem is that there hasn't been time for nature to select for this trait. Evolution doesn't work by "choosing" the best solution to a problem. It works by randomly coming up with billions of "solutions" and letting mother nature weed out which ones work and which ones don't. In this case, the virus spread quickly, had very few life cycles, and actually started showing the trait very early on (the zombies avoided the soldier with a bum leg - which by the way how is that terminally ill? Wouldn't most of the world be safe if a hurt leg is all it took for the zombies to avoid you? If you fall down while being chased wouldn't that be the zombie equivalent of sliding safely into home base?).

#3 - The "Camouflage"
A zombie "vaccine" of sorts is created. It's a hybrid meningitis bacteria that tricks the zombies into thinking you're terminally ill.

Why it bothered me
Vaccines are, in many cases, literally this exact thing. There's already a vaccine for meningitis that should be administered starting at 11 years old. Why wouldn't that work as zombieflage¹? Talk about herd immunity - our vaccines in this scenario would literally be immunity from a herd (of zombies). If weakened bacteria were all we needed then this should have never been a problem.

But let's step away from vaccines. Maybe vaccines won't work in this universe because they aren't healthy bacteria. Even so, we are full of bacteria. It's everywhere, no matter how clean you think you are. If zombies don't attack a human that is infected with bacteria, then we're all safe. After all, we're mainly microbe:





But maybe I'm making a bigger deal than I should about all of this. After all, it is just a movie . . .



Notes
[1] It's camouflage, but for zombies. Stay with me, I'm making up words in this post.


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Recently, a friend on Facebook alerted me to an article claiming that:

"The World Cancer Research Fund (WCRF) has completed a detailed review of more than 7,000 clinical studies covering links between diet and cancer. Bottom line: Processed meats are too dangerous for human consumption. Consumers should stop buying and eating all processed meat products for the rest of their lives."

That is a pretty serious claim. Processed meats are pretty common: Hot dogs, sandwich meats, bacon . . . WAIT. Bacon? Are you serious? The World Cancer Research Fund has said that bacon, even in small amounts, is dangerous for human consumption? Please, say it isn't so!

Or, if you won't say it isn't so I will . . . it isn't so. The World Cancer Research Fund said no such thing. They even responded to this article on their own website, saying:

"The articles talking about processed meat being 'too dangerous for human consumption' are unhelpful and scaremongering."

The WCRF also pointed out that the "recent review" being talked about was performed in 2007. A more recent meta-analysis shows that while the question of red meat consumption is very much resolved (eating >120 grams of red meat per day raises your risk of cancer by 13%), the question of processed meats is not as clear. Although review of the available literature shows that 50 grams daily of processed meats raises your risk for colorectal cancers by 19%, the p-value, which is a measure of the significance of an effect (the lower the value the more significant) was pretty high. The p-value was 0.46. Usually you want to see a value <0.05. The red meat p-value was <0.001, so ya, don't eat red meat every day.


So, to recap that last paragraph (if I lost you in the numbers): Don't eat red meat every day, and avoid processed foods. But what does that even mean? The WCRF uses the same language, and it's frustratingly ambiguous. Does "avoid" mean (as the first article suggests) that all processed foods are "too dangerous for human consumption", or does it mean that you should just try to eat less? In the WCRF's response to the "scaremongering" article they say that there would be 4000 fewer cases of cancer if people ate less than 70 grams of processed meat per week ^{[citation needed]}. However, they stress that avoid does not mean completely remove from your diet. Instead, they advocate a balance. Again, to them this means less than 70 grams per week, while the recent meta-analysis I found said less than 50 grams daily. That's a little less than two hot dogs per day or one-quarter of a large sandwich meat container.


Sodium Nitrite
One chemical that is specifically pointed out in this debate is sodium nitrite (NaNO₂). I'll admit, this is not a very welcoming image to see on the chemical's warning label:


But, we can't let that be the end of our research. What is sodium nitrite, and should you completely avoid it?

Let's answer the cancer question first:

"The National Academy of Sciences, the American Cancer Society and the National Research Council all agree that there's no proof of cancer risk from consuming sodium nitrite."

Now, I agree that the source of this statement isn't the strongest I could provide, but the conclusions agree with the Material Safety & Data Sheet for sodium nitrite, which place it in the "unknown" column for cancer, so I'm using it. Sodium nitrite has not been shown to cause cancer. Let's move on to what sodium nitrite is, and where it's found.

Sodium nitrite is used as a preservative. Now, I hate that I have to explain this, but that doesn't mean that it makes your food dangerous. That's a common thought. Preservatives are bad. Always. That's a statement that's not supported by science though. In fact preservatives are used to . . . preserve your food. Specifically, sodium nitrite keeps botulinum, one of the most deadly of all toxins, from growing in your food. To put this in perspective, botulinum toxin is fatal at a dose of about 0.000000002 grams per kilogram of body weight. If given a choice between botulinum toxin and sodium nitrite I choose sodium nitrite every time.

But, maybe that's a false choice. After all we could just eat foods that don't require chemical preservatives, right? Let's say, for example, spinach, carrots, and celery. These fresh vegetables must be an excellent substitution for foods high in preservatives, right?

Well, as far as the sodium nitrite content goes, not really. Fresh vegetables contain sodium nitrate (NaNO3), which your body converts to sodium nitrite (NaNO2). So if you are worried specifically about sodium nitrite in your food then you need to stay away from a lot more than just processed meats (Please note: I am not saying that processed meats are as healthy as fresh vegetables. I'm saying they both contain similar amounts of nitrates/nitrites).

So should I change my diet?
Frankly, everything can give you cancer - it just depends on who you listen to. Here is a pretty extensive list of things that have been reported (by The Daily Mail) to cause cancer. Some of the entries are ridiculous, some are contradictory, and some are just plain wrong. The important thing to remember is the dose determines the poison. That is, just because something in large amounts will increase your risk of cancer does not mean that small, controlled, balanced portions of that same thing will give you any problems at all.

Should you change your diet? I don't know. Do you eat more than 50 grams of processed meats every day? If so you might want to change that. As for me, I already eat less than the recommended amount of processed meats, so I'll enjoy a hot dog every now and then or some bacon when I get the chance.

Ok, so right now Facebook is full of people posting pictures of the moon.

Yes, it is a super moon.

No, you can't tell just by looking at it.

A super moon happens when a full moon coincides with the time when the moon makes its closest pass to the earth. Tonight the moon does appear larger. But by how much?

Ahh, the internets. A delightful distraction, a humongous time sink, an amazing educational resource. Unfortunately, they are also a terrible source of misinformation if you're not careful.

I recently came across this BuzzFeed article entitled "8 Foods We Eat In The U.S. That Are Banned In Other Countries." The article lists food additives that are not prohibited by the FDA, but are prohibited by its counterpart in other locales. Among the list are such items as rBST, potassium bromate, and arsenic. For each item, we are told what the item is, what it's used for, why it's dangerous, and where it's banned.

The "science" upon which this article is based is at best misleading and at worst an outright lie. Over the course of several posts, I will deconstruct the particularly egregious errors.

Brominated Vegetable Oil
What it claims: "Bromine is a chemical used to stop CARPETS FROM CATCHING ON FIRE, so you can see why drinking it may not be the best idea."

Why it's totally bogus: This article tries to compare the effects of elemental bromine (an admittedly toxic liquid) with brominated compounds, in which a bromine atom is attached to one of the carbons in vegetable oil. This may seem like a logical comparison, but it's actually a huge fallacy. Allow me to demonstrate by analogy:

Carbon and nitrogen are, arguably, two of the four most common elements (along with hydrogen and oxygen) for our bodies. Amino acids (the building blocks of proteins) always contain multiple carbon and nitrogen atoms. But what do you get if you have a single carbon atom triple bonded to a single nitrogen atom? CYANIDE. Yup, that's right folks, that nasty poison that smells like almonds (at least according to Law and Order). You cannot judge the health effects of a compound based on its constitutive elements. They way they're bonded radically changes the way that they behave in the body.

Ok, so what about the claim that "BVO is linked to major organ system damage, birth defects, growth problems, schizophrenia, and hearing loss."? Well, if you look at the link provided, it tells us that "In 1997, doctors were stumped by the case of a man who came to the emergency room with headaches, fatigue, and a loss of muscle coordination and memory. He continued to get worse over time, and eventually he lost the ability to walk. A blood test found sky-high levels of bromide. The source? The man had been drinking between 2 and 4 liters of soda containing brominated vegetable oil every day. He needed dialysis but eventually recovered." That, is, as far as I can tell, the ONLY evidence that there might be deleterious effects from BVO's.

Let's take a look at this claim for a second. The man was drinking, and I'll put this on a second line for emphasis:


To put this in perspective, if you drank that much natural, pure, fresh squeezed orange juice, you would probably get massive diarrhea. Of course you're going to see health effects if you drink that much of pretty much anything on a regular basis. Heck, drinking too much WATER can kill you (looks like you can overdose on homeopathic remedies after all).

So what?
Someone was wrong on the internet. I wrote a post explaining why they were wrong. Who cares? (Besides me, of course; I care a lot.) Frankly, I didn't even make a very strong case the BVO's are safe, just that Ashley Perez's claims were unsubstantiated. Consider the following logical "proof":


This blatant abuse of logic should make anybody cringe. Note that despite the logic being faulty, the conclusion happens to be true. But substitute "Woods Cross Wildcats" (my high-school football team) for "Chicago Bears," and the same argument suddenly supports a ridiculous conclusion. Heck, exchange "Chicago Bears" for "The sofa in my living room," and I could make a killing selling autographs. If you didn't know anything about American Football, would this kind of logic be helpful in determining whether someone/something played football professionally? Ultimately, it is important not simply to arrive at the correct conclusions, but also to arrive at them using correct principles.

Maybe BVO's are harmful. Maybe they're not. But wouldn't you like to find out, rather than simply jump in fright every time someone mentions a molecule that you've never heard of before? Chemophobia all boils down to a fear of the unknown. Not sure what something is? Treat it like it's evil, just in case. Never heard of a food additive before? It must be bad for you.

The Good

#1 - New Friends/Old Friends
I've always met at least one great person at every conference I've gone to, and since I met them at a conference there's a good chance I'll see them at a later conference. It's fun to have friends and acquaintances from around the globe. It's even more fun to catch up with them.

#2 - Arguments
I love it when, after an oral presentation, you see someone rush up to the microphone. It usually means an argument is about to break out. Science isn't . . . well I guess the colloquial way to finish that phrase would be "Science isn't a science". We don't know everything and we don't [mean to] pretend that we do. When two competing theories meet at a scientific conference it's not only good for the field - it's downright entertaining to watch.

"Good info. Bt what is d-orbital ?" 

Synthetic Chemicals!

Carl Sagan is an internet hero. Even now, some 17 years after his death, the words of Carl Sagan resound as a clarion call to science advocates. Sagan's biographers, however, claim that his popularization of science is what kept him from membership in the National Academy of Sciences. The so called "Sagan effect" is the belief that contact with the public is inversely proportional to academic achievement - those who have risen to the top of the "ivory tower" of academia wouldn't need to speak with the public. Therefore, if a scientist is spending time popularizing science he must not be a real scientist. The evidence, in fact, suggests the opposite is true, and Carl Sagan himself was a prolific scientist.

I don't believe the Sagan effect is of any current concern (an opinion I've had for some time and recently saw that Phil Plait agrees with me). I think scientists are much more willing (even excited) to share their results with the public - a change that can probably be itself attributed to Carl Sagan. Younger scientists, many of whom were drawn to science by the Carl Sagan/Bill Nye types of activism, are eager to continue the science outreach that brought them to science. They not only accept science outreach, the embrace it as a necessity. The modern Sagan effect isn't to discount a scientist because they seek to popularize science, it's to criticize a scientist that "dumbs science down". I can think of two specific examples:

1. "I F***ing Love Science"   

This wildly popular Facebook page (5.4 million likes) just may be the greatest science outreach success in the last 15 years. Elise Andrews has a massive audience willing to hear daily updates from the scientific community. There are those that criticize the page for not being science enough (most famously this one).

Now, to be honest I agree with some of the criticism. I have seen plenty of misinformation on "I F***ing Love Science", and the moderators of the page do very little to clarify misunderstandings. This is true both for inaccurate content and misunderstandings presented (and perpetuated) in the comments. When you control the most popular science page on the most popular social media site that comes with responsibility - responsibility that can't be shrugged off like it seems "I F***ing Love Science" does.

That being said, "I F***ing Love Science" is successful at gaining a new, larger audience that is interested in science. A great addition to the page has been a "This Week in Science" infograhic that shows somewhere around 6 advances reported in science literature every week - complete with sources for those that want to read more. Elise Andrew isn't doing a perfect job, but she's reaching a large audience and doing real science outreach. True, not everyone that subscribes to her page will become a scientist, but they are becoming more scientifically literate. 

2. "MythBusters"   

Over and over it seems that I hear people criticize the MythBusters for poor experimental design or misrepresenting science. I've said before that science, the MythBusters way, is a great advancement in science outreach (and Kyle Hill agrees with me). It is true that the MythBusters don't present a rigorous approach to experimentation. However, and more importantly, they show their audience that experimentation is possible. 

These are just two examples of the modern Sagan effect. There is no need to call out "dumbed down" science as wrong. Science was meant to make our complicated universe more understandable. Communicating science correctly, then, means to simplify a complex idea to the level that it can be understood. If someone walks away from science because they are "too stupid" we have failed miserably.