Past Advice

Fizz, fizz, plop, plop?

Dear Doctor Ninja,

I’m a 27 year old woman who is trying to lose weight. I switched from regular soda to diet soda, but I’m worried about some news that the sweetener in the diet soda will make my gut health worse. I like the flavor of soda and the fizziness, and the diet soda keeps from from drinking the regular stuff, but I also worry, since gut health seems to be so important.


G. Utrot

Personally, I think the jury is still out on what artificial sweeteners do to the bacteria in your gut in terms of whether the changes that seem to have been reported have any impact on you. And while there are some diseases and conditions that are directly caused by problems with gut flora, they’re not generally ones that can be fixed through diet alone.

The answer to your question lies more in the realm of what it takes to dislodge your dieting sanity. If diet soda is what makes the difference between sticking to your diet and achieving weight loss, and if weight loss is your major goal, then I say, take the theoretical hit (and I do think it’s theoretical) and lose that weight. If diet soda is something that’s just, “nice to have” and you can stick to your diet whether you have it or not; AND the theoretical risk bothers you that much, then consider something else that might be just as refreshing or fizzy that might be sweetener-free.

There’s also the idea that switching is the first step to “quitting”, if that’s also a major goal. Tastes are changeable. You can condition yourself out of a soda habit, just as much as you can condition yourself into one. The benefit of a diet soda is that it allows you to quit or reduce on your own terms without having to worry about the calories. Not everyone can go from full-sugar soda to plain water in one giant step.

The decision you made the day you switched from regular soda to diet isn’t carved in stone. You can choose to taper off diet soda in favor of other non-caloric drinks when it feels time and you can do it as fast or gradually as you want; if ever.

Birth and Bias

Dear Doctor Ninja,

I’m a first time mother and I’m learning about all the pain management techniques, medications, and birth interventions. I can’t help but dread the process of delivery considering what mainstream media and fear-mongering mommy groups portray. So many women are traumatized by their birth experience and I feel that health care standards are too low. (For example, if 80% of women have perineal tears, why has nothing been invented or researched to decrease this statistic? Compare this to when a small portion of men reported slight negative symptoms for potential male contraceptives, clinical trials were halted immediately.)

At the same time, I have unwillingly curated the narrative that the health care system is highly patriarchal and practices have been established by men/male doctors without considering the comfort and verbal symptoms relayed by women. Several studies have cited that when women present verbal feedback about signs and symptoms, they have been neglected or sent for psychiatry treatment instead of having physical treatments. Interventions such as Vacuum Extraction, Forceps, Episiotomy seem highly aggressive with increased harm to mother AND baby.

Where do / How have birth intervention practices come about? Who are some thought leaders in the specialization? Is my narrative untrue or distorted? What can be done individually or nationally, to push the standard for better health care for women?


Feminist First Time Mother

First of all, congratulations on the coming new chapter of your life!

What I see in your letter is the fear of not being heard, and the fear of your needs being ignored, misunderstood, and the fear of being mistreated outright in a situation where you feel you have very little control. Pain is the great disabler–it changes what we want; how we see the world, and others; and our priorities. So, confronted with a scenario in which pain seems to be an inevitable, and predictable part of the event, you are wise to look ahead into the future from a place where pain doesn’t yet have quite this power over you.

There’s nothing distorted by your narrative. Tears happen. Traumatization happens. As with all things, childbirth carries risks that are unique to every mother. And yes, there are studies that have shown that women can be taken less seriously when they talk about pain. And interventions are used when the judgement of the physician deem the risk to be high enough to the mother or baby to use them. There isn’t a frame of reference in which these events don’t exist; and we would be wise not to ignore them.

But, regardless of where birth intervention practices come from, and who the so-called thought-leaders in obstetrics are, and what can be done to push for better healthcare for women (all topics of great significance and interest), the singular reality is this: You are going to have a baby. You, specifically. This baby, specifically. And with the attendance (if you’re choosing to have a hospital birth), of a specific physician or group of physicians, as well as the entire healthcare team that will be part of the process. AND hopefully, whoever you’ve chosen as your “helper”. You might feel that standards of care in general are quite low, but it’s the standards and quality of the specific care you’re going to receive that matter in this scenario.

When it comes down to you and this event, reassurance and trust are paramount, regardless of who is present and making decisions. What can you do specifically to push for better health care for yourself? Book that appointment with your doctor. The one who you’re hopefully seeing for pre-natal visits. Make it clear that you need a chunk of time and that it’s not a quickie visit. Be prepared with your questions; but remember, that this visit (or series of visits) is about your fears and worries, and not about getting clinical information. Redirect your doctor if they seem to be talking about specific procedures in a general and abstract kind of way, as opposed to addressing how and why you feel the way you do. Because doctors are human too; they have their own fears and worries. Being “cold and clinical” can be a default kind of place when the conversation becomes uncomfortable.

Find out if the location  you’re planning on giving birth has tours. If they don’t, ask if you can have one. Bring your helper with you. Find out whether you’re in a practice that has group call for deliveries. It’s okay to meet those other doctors too, depending on how big the call group is (otherwise, it might be a lot of appointments!)

Part of what doctors are paid to do is to listen to you tell them your worries and fears. The other part is to be good at all of the other skills that are needed to provide care in the best interest of their patients. But sometimes they forget that this is your first birth and not your 1000th. And it’s okay to remind them of that too.

As for what can be done about raising the quality of healthcare for women in general:

  1. Take your own experience forward, including this one, and consider the spaces in which you see room for improvement

  2. Get involved locally with patient advocacy groups and develop your own sense of the story through hearing the stories of others, both positive and negative. It’s only through hearing and seeing others that the question of an untrue or distorted narrative can be answered. Global practice is shaped by the critical mass of local ones.

Lollipops and Island Dreams

Dear Doctor Ninja,

I’m planning to continue my studies with a Master’s degree.

I really like to keep up with the latest research and I would love to contribute to my field as a researcher. I’m having trouble deciding which degree to pursue, if I should strive for a MSc within my field, or one in Research Methods. What should I base my decision on?

Is a coin flip ok?

PS: I hope it is not a very specific question.


Fiddy Fiddy

I really wish you had been more specific. But I’ll give you the best answer I can.

You don’t mention whether the kind of Masters you’re looking to pursue is a course-based program or a thesis-based program. A course-based Masters in Research Methods is actually quite abstract, since you’re not really doing as much design work. It’s like going to art school and learning about all the _things_ you need to use to draw, or sculpt, but never actually drawing or sculpting. A thesis-based Masters is going to have more practical components, but you can’t study Research Methods in a vacuum—they need to be applied to a field of some kind. In a thesis-based non-Research-Methods program, you can still learn a lot about Research Methods, depending on who your supervisor is, and what kinds of courses you take. It’s not really an either/or decision.

A coin flip is either totally okay, or not okay at all. If the coin flip reflects your overall ambivalence to either pathway, I would want to encourage you to do some soul searching as to why you want to do a Masters in the first place. While it is only 2 years of your life (hopefully, if you finish on time; and completion time IS important), every graduate student experiences “the dark times” in their degree where the original reason for going in the first place is what gets them through. If however, you feel some sort of strong pull that feels equal in both pathways, and see yourself equally “happy” (is there really such a thing in graduate school?) in both scenarios where you have convictions that will get you through those times that you just have to grit your teeth and push through, then flipping a coin is as good as any way to make this decision.


This question also sounds like these are pathways you are simply contemplating at this time. Both options are just potential pathways, not real ones. If you have two offers in your hands, that’s a different story. If you haven’t applied to either programs, then you are making a decision between two equally unreal outcomes. It’s like deciding whether you’d like to have a bag of lollipops or a small tropical island. If you don’t have either of them at your disposal, then you’re just making a decision about which one sounds better to you today. If, however, there’s a bag of lollipops and a deed to a small tropical island in front of you and you are in some sort of odd game show where you have to choose one, then go for the one that has now become more attractive, or flip that coin.

In short, you don’t need to make this decision today, because one or (and hopefully this isn’t the case) both of these options might not actually be available to you. If both options are available to you in a concrete kind of way, THEN, you may find that when things get really real, that you see the choices differently.

You can date both options at once until one becomes more attractive than the other—either because you get to choose between them, or because one dumps you first.

Push-ups and your pumper

Dear Doctor Ninja,

I’m a guy in his mid-30’s. I just heard about a study that says if you can do 40 push-ups that your risk of a heart attack is much lower. I can’t do 40 push-ups. If I train myself to do 40 push-ups, can I prevent a heart attack?


C. Hesturts

This study really made the headlines, Mr. Hesturts, didn’t it? Some of devil is in the details here—mostly having to do with “What is a push-up?”

Most people know what a push-up should look like. But for firefighters, the test that is performed has some pretty specific parts:

  1. your chin has to touch a 5-inch tall object (this seems pretty mean for tall people)

  2. your back has to be neutral (no sagging)

  3. you have to do them to an 80beats-per-minute metronome

  4. you have to do the push-ups within 2 minutes

But that’s not all, you also cannot:

  1. Do more than 3 incorrect push-ups

  2. Fail to maintain continuous motion with the metronome cadence

  3. Have any joint or muscular pain, or dizziness or unsteadiness or chest pain while you are doing the test.

So what does this all mean? Let’s break down what it really takes to do 40 push-ups:

To do ONE push-up, you have to have:

  1. the ability to stand or kneel

  2. the ability to get into push-up position (bend over, support weight with hands)

  3. the ability to keep your body straight

  4. the ability to lower yourself to the 5-inch object

  5. the ability to push back up

  6. the balance to support yourself on two hands and feet together

  7. the coordination to get down and up as well as to keep time with the metronome

To do FORTY push-ups, you have to have, in addition:

  1. muscular endurance in your chest, triceps, shoulders

  2. the ability to hold the rest of your body (some might call it your “core”) in a specific position

  3. sufficient strength to do one push-up

A push-up defined in this way isn’t a simple movement. In the end, this has more to do with exercise capability and the ability to exercise at all, than it does directly to do with heart health. Certainly the two are linked—the ability to exercise has to be satisfied before one can exercise and THEN exercise is linked with lower rates of heart attacks. But really, this study is one that compares people with higher-than-average exercise condition with people with much-lower-than-average exercise condition within a group of people (firefighters) who generally have better-than-average exercise condition.

What’s interesting is that we aren’t told of those men in the 0-10 push-up group, how many could do 0 push-ups vs any non-zero number. The kinds of things that would prevent you from doing a single push-up range from being extraordinarily weak, to a wide range of medical problems that are already linked with bad outcomes of all kinds, including heart attacks.

The other interesting number in this study is that of 1104 participants, the number of heart-related events was 37. In the general population, over 10 years, we would expect there to be about 55 first-time heart attacks (both fatal and non-fatal), so taking this into consideration, firefighters, no matter how many push-ups they can do seem to be at lower risk for heart-related events than the general population. However, amongst the firefighters who could only do 0-10 push-ups there were 8 heart-related events, which is almost 2 times higher than the general population rate which we would expect to be around 3 or 4.

The main message of this paper is that a push-up test doesn’t require a lot of fancy equipment (you need a 5-inch tall thing that will stand on its own, a metronome, and enough floor space to do a push-up without touching any walls) and that there might be a link between being able to do 40 push-ups and not being able to do 40 push-ups within 2 minutes and your first heart attack. Oddly, I think the floor space is more the barrier, given how tiny examination rooms are in doctors’ offices.

If you can’t do 40 push-ups now, then there’s going to be a certain amount of work that has to be done to get to 40. It might be a lot of work if your current number is less than 10 but more than 0. That work would be exercise. So can you prevent a heart attack if you train yourself to do 40 push-ups? Well, if exercise is linked with a lower risk of heart attacks, and you have to exercise enough to have a body that can do 40 push-ups, then yes, you’ll reap the rewards that come with that, because to get to 40 push-ups and stay there, you have to develop a habit of exercise.

Whether or not it will prevent a heart attack depends entirely if you were going to have one in the first place.

Disappointment, or error?

Dear Doctor Ninja,

I am a reasonably fit 57 year old male. Nearly three years ago, I had a DEXA scan that revealed I had about 500g of visceral fat. It didn’t seem critical that I lose it, but I thought it would definitely be good if I reduced it. Between the scan and November last year, I hiked 1000km over four separate hikes, rode my bicycle a lot, became a vegetarian and generally reduced drinking alcohol. In November last year, I started an intensive 12-week workout program, which included five weight-training workouts and one aerobic workout every week. I also didn’t have an alcoholic drink for 100 days. Then I had another DEXA scan. I felt sure that my visceral fat level would have dropped. Instead, it was 160g more, causing me to exclaim mutha-ninja! Would you have any advice on the best ways to reduce visceral fat?


Fujibayashi Nagato

First off, congratulations on making some great lifestyle changes that seem to be working for you!

Before I get into your question, I think it’s important to note a number of reasons why you might have been disappointed in your perceived lack of progress.

In an ideal situation, if you wanted to know how effective your 12-week program was going to be, you would have done a DEXA scan before you started. Since it’s been 3 years and a bit since your DEXA, we really don’t have a good idea of what your visceral fat has been doing. Were you possibly even higher than 660 grams 12 weeks ago?

The other consideration is the nature of the DEXA scan itself. Again, in an ideal situation, you would have a DEXA scan with the same scanner, as different scanners use different algorithms to calculate the various tissue masses. You didn’t mention if this was a whole-body DEXA scan or a single-level one, which can also affect things, particularly if your previous scan was one and your latest scan was the other.

Even measurements with the same machine carry measurement error though. Fat mass variation between scans of the same person (with no change in body composition) can be in the 150g range, which means that an increase of 160g of visceral fat from your previous scan 3 years ago could be due to just the variation in the machine, as opposed to an actual meaningful increase in visceral fat.

You can’t reduce your visceral fat to 0. The average amount of visceral fat in healthy 20-30 year old males likes somewhere in the 400g range. You’re not 20-30 years old anymore, so the average amount of visceral fat in a healthy 50-60 year old male is expected to be higher as visceral fat tends to increase as we age, even if our waistlines don’t.

Visceral fat is contrasted from the fat that sits under the skin (the fat you can pinch, also called subcutaneous fat). It’s the fat around your organs. Visceral fat plays an essential role in organ health as both a source of energy as well as padding; it’s only when visceral fat is in _excess_ that it becomes a problem. Its accumulation is directly related to fat accumulation in general. There’s no known effective way to directly target visceral fat without making changes in other fat stores.

Fat, in general, does not accumulate when there’s no difference between the energy you’re spending vs the energy you’re eating. So the best ways to prevent visceral fat accumulation, or to reduce it, are the same ways to lose fat in general, which come down to controlling the “energy in vs energy out” equation. While there are still many small controversies about which diet is best and whether there can be ways of trying to get around this energy balance requirement, it still seems to bear out that it’s the main linchpin of the matter. How you choose to manipulate energy balance (whether through vegetarianism, or carnivorism) depends mostly on the priorities you have on what, of many factors, play into whether you can stick to an eating style or not. “Diets” are mostly mind-tricks that we use to allow us to execute a habit of eating within energy balance—some people need different or stricter rules than others.

The solution to dilution is not pollution

Dear Doctor Ninja,

I’m an undergrad who just started working in a research lab. In the lab today, I couldn’t think up the mental maths in order to come up with the serial dilutions we needed to do on the spot. The graduate student assisting me kept providing assistance. I would ask, she would answer. I would zone out because I was freaking out about how dumb I sounded, I would ask her to repeat. It was humiliating. Even when I asked questions, I wasn’t fully understanding what was happening, even though I thought I was in the moment.

What I really needed was a pen and paper; that always helps me clear my head when things get jumbled. However, that isn’t an option, because 1. the math really isn’t that hard (i.e. when I’m not freaking out) and 2. we have to keep a sterile environment for the experiment (i.e. no touching things other than the pipette and the test tube).

How do you keep your cool in situations like these? How do you get better at mental math? Most importantly, how do you get better at taking orders and following instructions (aka: listening skills)?


Upset Undergrad

First of all, I think it’s important to give yourself a break. You’re new. You’re excited and you want to impress. If you didn’t have these qualities, they wouldn’t have hired you. Being nervous when there’s both data and impressions on the line is normal and I’m pretty sure you’re not their first nervous student. They get it.

I’m going to answer your last questions first.

You learn to keep your cool and get better at mental math by doing them. Your grad student is there to help you and to make sure that your practice is perfect. They’re not going to let you go off the rails. So just focus on the work, and allow yourself the space to separate your work from how you see yourself as a person (i.e. you are not your work). In a short time, you’ll hit your groove, and you’ll be looking for the next challenge.

But, more importantly, understand two things:

1) You are an investment in this lab. Data does not collect itself. Experiments don’t just do themselves. Both data and experiments cost money. You cost money. It is in the lab’s best interests to keep you (especially after they’ve trained you), and it’s in their best interest for you to produce the best work upon which their findings and publications are based. Reagents and equipment are expensive, whether you’re working in sterile conditions or not. It is far better for THEM that you are sure the data you are generating/collecting is of the highest quality than it is for them to be worried about how flustered you might be getting. So it’s also in their best interests to support your development, and this means supporting you getting better at what you do.

2) Practically, I’m also horrible at mental math. In fact, a lot of mental math comes down to memorizing the common stuff, or printing it out, spreadsheet style. If you know what kinds of dilutions you need to do and if they tend to fall in the same patterns over and over (hint: ask your grad student), then it’s actually in your lab’s best interest not to rely on mental maths at all, because it just takes one slip of one number to render an experiment an utter waste of time and money. If you work under sterile conditions, then taping this spreadsheet to the wall or the table or anywhere you can see it while you’re working is potentially a much better (and more importantly, less error prone) solution than you doing any math in your head.

It will get better. Promise.

There’s no ‘U’ in diet. But there is an ‘I’

Dear Doctor Ninja,

I’m a 33 year old female. I started a new diet this year, and I’ve lost a bit of weight already. It feels like I lose the same 15 pounds every year no matter which one I try. I’m starting to wonder which diet would be best for me to lose the weight permanently. There are so many articles on so many diets, that I don’t know how to choose! Help!

F. Ifteen

There are a couple of things that almost all diet-type science folks agree upon:

  1. If you’re not eating enough food, and don’t have a medical condition, weight gain is nearly impossible. And by nearly impossible, they mean that if it were to happen—that someone gained substantial amounts of weight while eating not enough food that could ONLY be explained by their food, that it would be a publishable case report in a very prestigious medical journal and you wouldn’t be hearing about it on a blog first because the news would be THAT big.

  2. A diet that cannot be followed by an individual, can’t produce results.

After that, it turns into a shitshow.

But, if we consider the these two things, a diet that will cause weight-loss really just has one purpose:

To give you a set of eating “rules” that you can stick to, that allows you to not eat enough food.

Not eating enough food is not the same as being hungry. And hungry is a state of mind that is driven not only by what’s in your tummy, but also when you’re used to eating, how much you’re used to eating, who else is eating with you, or at the same time as you, how certain foods make you feel, what memories certain foods evoke, and what food means culturally to you and what your beliefs around what the function of food is, apart from just calories. And more.

Diets aren’t made for everyone (one might even argue that they’re not made for any one). They make assumptions about what people will and won’t tolerate. For some people, eating three meals per day, no matter what is in those meals is mandatory. For other people, feeling full is more important than eating three meals a day. The range of priorities that we each MUST have in order to feel satisfied (or at least not angry) about our food is as wide as the number of diets available to us.

Thinking about what’s important to you when it comes to food and then picking the diet that respects those values is more important than picking a diet that is “scientifically best” (as though there was such a thing) and changing yourself to fit it.

The diet you pick is like picking who to date. You have a certain set of core values that you won’t give up for anyone. A compatible partner respects or even shares those values. Likewise, all relationships require some degree of compromise. But that compromise doesn’t involve changing who you are fundamentally. Your relationship with your diet shouldn’t be an abusive one.

And just like we outgrow some relationships, we can outgrow our diets. The diet that you partner with that enables you to lose those 15 pounds might not be the diet that enables you stay at your new weight, because at your new weight, some values can change. The good news is that breaking up with your old diet doesn’t have to be full of angst. You don’t even have to text it.

Arthritis and the price of wine

Dear Doctor Ninja,

I’m a man in his 60’s. I read a news story about how having things called Heberden’s nodes on your fingers means you probably have bad arthritis in your knees. I have these nodes on my fingers and now I’m worried about my knees. Should I be seeing my doctor about this?

B. Umpy

Heberden’s nodes are usually linked with finger arthritis. They look like small bumps on the back of your finger at the finger knuckle closest to your finger nail.

But what we are dealing with, in both the case of Heberden’s nodes and in the case of the study cited in the news article is the definition of arthritis, or rather the ways in which the word “arthritis” is used.

Cartilage is the extra layer of stuff that caps many of the bone ends in your body to allow them to move smoothly against each other. Strictly speaking, arthritis is the term used to describe any damage or wearing away of cartilage in a joint. We can tell there has been loss of cartilage either by looking at it directly with a camera in the joint (called arthroscopy), or with surgery (not that anyone would open up your knee wide open just to look in it); but also indirectly from tests like x-rays or MRI’s. X-ray or MRI are the most common ways to tell if there’s loss of cartilage.

However, that’s not the way most people think of arthritis. Most people think of arthritis as joint pain caused by loss of cartilage in the joint. Most people think of things like knee and hip replacements when they think of arthritis.

When a study is published that says that bumps on the back of your fingers are potentially a sign for arthritis in your knees that will get worse over the next 2 years, this can understandably cause some distress.

Here’s the thing: There are lots of people out there who have loss of cartilage on their x-ray or MRI who don’t have any pain or loss of function. And this has also been studied.

If you have arthritis (i.e. loss of cartilage) but no pain or loss of function, it is generally considered a non-issue. It’s only when the arthritis (i.e. loss of cartilage) comes with pain or loss of function that anything needs to be addressed.

So what about this study about bumps on the fingers and knee arthritis?

The study in question was a study looking at the association between the bumps on the fingers (Heberdern’s nodes) and the kinds of findings we associate with loss of cartilage in the knee. However, the study in question did not look at whether these findings were related to pain or loss of function.

However, since we know that a lot of people (50% in some studies) have “arthritis” on x-ray or MRI don’t have any pain or loss of function, what does it mean when someone else says having nodes on your fingers is linked to “arthritis” on MRI? How does knowing that your MRI will be more likely to look worse in 2 years help you change anything about the way you live, given that you might still only have a 50% chance of having pain with the worse-looking MRI?

A more expensive wine might make for a better story for whoever buys it, but the price on a bottle of wine doesn’t always make the wine taste better or worse. Price might be linked to taste rating if you can see both the price and taste the taste, but if the wine tastes fine (or even good, or amazing), and the price is low, does the price matter?

Fewer Flying F’s for Fighting Flu’s

Dear Doctor Ninja,

Are flu shots part of the anti-vaccination movement? After my social media post yesterday about my 5 year old and I getting our flu shots, I’ve heard from pro-vaxxers, anti-vaxxers, and people who give flu shots separate consideration from vaccines. What’s the story?

P. Rick

To answer your first question: Yes. Flu shots are vaccines and therefore would not be supported by people taking an anti-vaccination stand.

But what is the story?

Throughout modern history, there have been outbreaks of viruses. The symptoms we think of as the flu are caused by many different viruses. The outbreak of 1918, in a time before we even knew influenza was caused by a virus, it’s estimated that 500 millions people caught the spreading strain (thought to be the H1N1 strain) and that 50 million people died from it.

Since the flu is caused by viruses, there are very few treatments to cure it once you have it. Anti-viral medications help, but usually only shorten how long you have symptoms and sometimes make the symptoms less.

Since so many different viruses cause the flu, a flu vaccine can’t protect you from all of them. Every year, public health scientists and doctors (for instance, at the CDC in the USA) look at the information about what flu viruses have been circulating the most. They then make an educated prediction about which viruses will be the most common in the up-coming flu season, which usually runs Fall to Winter and vaccines to those predicted viruses are produced. Since it takes 6 months to mass-produce a vaccine, they have to commit to the prediction by February or March before the fall (September/October) in the Northern hemisphere, and September or March before the fall (February/March) in the Southern hemisphere.

As the saying goes, “It’s always twelve o’clock somewhere,” which means it’s also flu season twice a year globally. Since each flu season runs for almost 6 months, that means it’s almost always flu season somewhere too.

The most common question posed about the flu vaccine is usually, “Why did I still get the flu even though I got a vaccine?”

First off, you can’t tell you’ve been protected against things you can’t see. So while you might have gotten the flu last year, it’s difficult to tell which virus you got and whether you were _also_ infected with one of the viruses that were in the vaccine last year where you didn’t get symptoms.

Secondly, since you can’t be vaccinated against _all_ flu viruses, you can still get “a flu”, just not from the viruses you had a vaccination for.

Thirdly, there are some viruses that are difficult to make vaccines for. When these types of viruses are the predicted viruses, even if the prediction is right, it can be difficult to make an effective vaccine against them because of limitations on vaccine creation and production technology.

Lastly, sometimes, the prediction is off. You’re vaccinated and protected, but not against the viruses that are the most common in your area of the world.

So the reason why some people give flu vaccines a different consideration from other vaccines is this uncertainty. There aren’t a lot of different kinds of germs that cause tetanus. There’s not much guesswork in creating a tetanus vaccine. Therefore, if you were properly vaccinated against tetanus, it would be nearly impossible for you to get lockjaw if you were exposed to the tetanus bacteria.

So why get a flu vaccine at all?

When the weatherperson tells you it’s going to rain, you bring an umbrella because you don’t want to get wet. Even if it doesn’t rain, you’re ready. And sometimes, even though you have an umbrella, it rains sideways, so you still get wet. Or, it hails golfball-sized hail, and the umbrella isn’t really that useful.

One reason to get the flu vaccine is to protect yourself against the predicted viruses that cause the flu. And if you’re in a category of health where getting the flu is potentially a disaster (like young children, or the elderly), then an umbrella even on a day where it might not rain is a pretty good idea.

But other reason to get the flu vaccine is if you’re around other people where getting the flu is potentially a disaster. The thing about the flu is that you can pass on a flu virus before you feel sick. If you’re immune to the dominant virus in your area, you’re much less likely to pass it on. You’re a virus blocker. You break the chain for that virus. Which means you protect others who are either unable to protect themselves, or aren’t as good at it as you. You’re like the person who doesn’t forward email from Nigerian Princes to your friends and tells your mother to stop doing that.

What you can’t see can’t hurt you?

Dear Doctor Ninja,

I Like most people, I’ve heard the vaccination debate rolling around for the last few years, especially after one of my favorite comedians took an anti-vax stand a couple of years ago. But it’s only now with my wife is 30 weeks pregnant that it’s feeling like a very real and personal decision we’re going to have to make for our child and family. This is our first child and we’re so excited but also worried. Both my wife and I were vaccinated as children but things feel different now. I’ve been reading about vaccination extensively but I still don’t feel confident about making a decision. Can you shed some light on the situation?

W. Orried

When I was a child, I got the chickenpox. I still have a scar on my nose from it. My mom calls it “proof” that I had chickenpox. Back then, there was no chickenpox vaccine.

We were a vaccinated family: Measles, mumps, rubella, polio, tetanus, diptheria and so on. If there was a vaccine against heartbreak, my parents would have given it to me.

Whether to vaccinate your child against any particular disease is not only a personal decision for you, but a personal decision for your child. The question you have to ask yourself is, “What are the kinds of things do you see that make vaccination feel like a wrong or a right decision?” And more importantly, “What are the kinds of things you aren’t seeing that also make vaccination feel like a wrong or a right decision?”

My parents grew up in a time and country where polio was a reality. They had either friends or friends of relatives who lived with the complications of polio; unable to move certain parts of their body. Polio was present in their lives, not just theoretically, but in a concrete, experienced way, even if neither of my parents had the disease.

When asked, “Would you like to give your child a series of vaccines that would prevent them from ever getting polio?” my parents’ answer was confidently yes.

What you see today is autism. Chances are you know someone who is affected by autism or has someone close to them who is affected by it. Even if you don’t know someone affected by autism, the volume of vaccine-autism material on the internet is so overwhelming that it can create the vividness to make it real enough for you. Even if you never look at vaccine-autism material, you’ve seen autism.

A Google search today for “do vaccines cause mental problems”, comes up with over 64 million hits, the first two pages of which are about vaccines and autism.

A Google search today for “hospitalization of child for flu,” comes up with just over 1.2 million hits, and the first two pages aren’t even about kids in the hospital with flu, but when you should take your child to the hospital if they have the flu. In fact, the only way to find anything about a child in the hospital with the flu is to search “child dies in hospital with flu” which still only comes up with only 16 million hits.

Even if every case of measles, polio, or even every case of hospitalized flu was reported on the internet, it would never catch up.

For you, autism is real. For you, unlike my parents, polio is only theoretically real. Polio is only theoretically real for you because of a concerted effort to eradicate it. You would be hard pressed to find anything on social media about how polio affects anyone around you. You can tell something is really good at preventing something bad, when we forget that that bad thing exists. You can’t see what is no longer there. The bad boy/girl trope exists because you meet all the wrong people until you don’t meet the wrong one. Until then, to you, the world is full of undateable people. But “bad boys”/”bad girls” exist only because the good ones do too.

Your personal decision has very little to do with herd immunity, or the greater good, or even which of the differing opinions is true. You want the best for your child. That’s what loving parents want. You want to make the decision that protects your child and gives them every opportunity to be the person they want to be, whatever it is they want to be. Fear that you can see and feel is stronger than fear that you can’t see.

We all have blind spots when it comes to making decisions, and the key to making a good decision is to make sure that you’ve reflected not as much on what you can see, but what you can’t see, because it’s not what’s being shown to you. Because the fear you don’t see, if you could see it, would probably change how you feel about this very issue.

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