Monday, August 25, 2014

Apple #682: Dog Days of Summer

It has finally turned humid this summer.  For weeks and weeks, the weather has been beautiful -- sunny, breezy, warm, and none of that oppressive humidity.  But a few days ago, we had a big fat thunderstorm, and it left a lot of that humidity behind.  Looks like it won't budge for the whole week, either.

Which makes me think, we have finally entered the Dog Days of Summer.

What does that mean, anyway?  I have always imaged it means this:

(Photo from Doggie Cakes)

(Photo by Snowlight at Flickr, sourced from Low Country Dog)

(Photo from The Pet Wiki)

The Dog Days of Summer: when the weather gets so hot, all the dogs are panting.

But no, that is not the correct definition.
  • The Dog Days refers to the position of Sirius, the dog star (No, not Sirius Black), relative to the sun.

Sirius is the brightest star in the constellation Canis Major (Bigger Dog). It's just below Orion -- the 3 stars of Orion's belt point to it.  The story goes that Canis Major is Orion's hunting dog.
(Image from

  • Ancient Romans noticed that during the hottest time of the summer, the brightest star in the night sky -- Sirius -- was rising and setting roughly the same time as the sun. 
  • Some people say the Romans thought that Sirius's conjunction with the sun was adding heat to the days, and that's why those particular days were hotter.  
  • In reality, while Sirius is the brightest star in the sky, it is much too far away for its heat to have any impact on us.  

Sirius is larger and brighter and hotter than our sun -- though it's too far away for us to feel its heat.
(Image from Astro Bob)

  • The Romans were pretty smart cookies, though, so they may have known this and simply been aware that the two were in the sky at the same time. 
  • Ah, yes, here we are.  An astronomer named Geminus wrote, around 70 B.C., "It is generally believed that Sirius produces the heat of the 'dog days,' but this is an error, for the star merely marks a season of the year when the sun's heat is the greatest." 
  • (So, Weather Channel and everybody else, quit making the Romans out to be a bunch of dummies.)
  • Knowing that the two stars were in the sky at the same time, the Romans named that stretch of days the Dog Days of Summer. (Actually, the time period goes from about 15 days before the two rise together through 15 days after)
  • Exactly what part of summer that happened is also now in question.  Because of the very slow change in the Earth's orientation on its axis, when Sirius rises with the sun now is slightly different than when it rose back then. 
  • Some say it used to happen from July 23 though August 23, or thereabouts.
  • Now, however, the Farmer's Almanac says the Dog Days officially happen each year from July 3 through August 11, and everybody more or less goes along with that.
  • You kids with your smart phones, you've probably got an app that allows you to point your phone at the sky and it will tell you where the constellations are.  If you don't, this app called Star Walk ($2.99) supposedly does just that. Get an app like this, and you can see for yourself where Sirius is, and whether we're actually in the Dog Days or not.
  • (I know, he fell through the portal and he isn't coming back.)

Monday, August 18, 2014

Apple #681: Airport Runway Signs

I have had a request!  Daily Apple reader Jamarcus wants to know, what do all those signs next to airport runways mean?  You know, the ones that look something like this:

This sign lights up so it will be visible to pilots at night. But what do the letters and numbers mean?
(Photo and sign from Astronics Corporation)

A very good question.  Something I have often wondered myself.

Before you can interpret the signs, it helps to know how things get named at airports.


  • There are taxiways, and there are runways.  Runways are the paved strips where planes take off and land.  Taxiways are the paved passageways the planes take to get from the terminal to the runway to take off, or from the runway where they've landed back to the terminal.
  • You definitely want to keep the two separate because you don't want one plane ambling down a runway as another plane is about to land there.
  • A lot more real estate is covered by taxiways.  Some of our airports are enormous, and a plane may have to travel quite a long way to get from the terminal gate out to the runway.  It will have to drive down a lot of taxiways before it gets to the runway.
  • Taxiways are indicated with letters, beginning A, B, C, etc.  All airports begin their naming of taxiways with A, and one taxiway can go for a really long way. So the signs you see from your airport window will most often have an A on them.  
  • Some airports are so big or have so many taxiways, they get up to G.  Theoretically, taxiways could be lettered all the way up to Z, and then get the letters doubled: AA, BB, CC, etc.  But in real life, it's rare that taxiways are named much deeper into the alphabet than G.
  • Taxiways can never be named H.  The letter H is reserved for helipads -- landing places for helicopters.
  • They can also never be named I or O, because those letters could be mistaken for numbers.
  • They can also never be named X because an X on a sign means the runway or taxiway is closed.
  • You will often see signs that combine a letter and a number, such as A1, or B3 (as above), or C2.  These indicate either:
    • a stub taxiway -- a connector that goes from a runway to a taxiway that runs parallel to the runway (a little cross-bar connector from a runway to a taxiway) 
    • or the exit or entrance connector that goes from a taxiway to & from the terminal. The connectors get named sequentially A1, A2, A3, etc. along the length of the taxiway.
  • Keeping all those rules in mind (and a few I've left out for brevity's sake), an airport also needs to make sure no taxiway has a name that could be confused with a runway, and no two taxiways have the same name. 

Well, this is hard to see. But the runways have the dashed lines, and the taxiways are thinner.  The taxiways are named, from top to bottom, A, B, and C, and the little connectors that go between the runways and the taxiways are named, from left to right, A1, A2, A3, A4, A5, A6, and A7, and then in similar fashion for the connectors that go off taxiways B and C.  The little taxiway that goes vertically, bisecting the runways and the parallel taxiways, is named J.  That one gets its own letter, as opposed to something like C5, because that's a high-traffic taxiway.
(Diagram from the FAA's Engineering Brief on Taxiway Nomenclature)

This isn't a real-life runway but a screen shot from a simulator, but it does the job for our purposes.  The runway is on the right, as indicated by the white markings. The taxiway, outlined in yellow, is on the left.  A taxiway stub connects the two.  The colored paint and types of markings is a whole other set of visual indicators for pilots.  
(Photo from SimFlight)

  • By the way, the names of taxiways are not pronounced as the letters (A, B, C), but by the names that correspond to each letter, according to the NATO phonetic alphabet (Alpha, Bravo, Charlie).   So taxiway A2 would be called "Alpha two."
  • Yes, this is the same alphabet popularized by Wilco's Yankee Hotel Foxtrot.


  • Runways get named using numbers.  The thing that determines which numbers get assigned to a runway is where the runway is relative to points on a compass.  Then it gets turned into a kind of code.
  • North, South, East, and West all correspond to degrees on a compass.  North = 360°, for example.  According to this runway code, you lop off the 3rd digit of the compass point.  So if a runway were pointing true north, it would get numbered 36.  For the 4 points of the compass, the code works like this:
    • North = 360° = runway number 36
    • South = 180° = runway number 18
    • East = 90° = runway number 9
    • West = 270° = runway number 27
  • But of course it's rare for a runway to be heading in exactly the position of one of the points of the compass.  So in most cases, the runway number is arrived at by rounding off ±5°.  Let's say a runway is heading 176°.  That's within 5° of 180°, so its runway number would be 18.
  • It is also of course likely that a runway won't fall within 5° of one of the ordinal points on a compass, so it is very likely that runways will be named other numbers besides these four.
  • Because there are only 360° on a compass, you can't have a runway with a number higher than 36.  Also, since North is indicated by 360°, there is no 0°, so there will be no runway named 0.
  • Finally, because you may be allowed to land on a runway from either direction, its name will often be expressed from either approach direction, as in ##-##.  The first number indicates the compass direction from one end of the runway, let's say, 22.  That means the runway's compass heading is 220° (or within ±5° of that).  So the second number will be 180° from 220°, which is 40°, which becomes number 40.  This runway's official name is therefore 22-40.
  • By the way, the runway numbers are not pronounced the way we normally pronounce two-digit numbers. They are said individually.  Not "runway twenty-two" but rather "runway two-two." Nine is pronounced "niner."  Yes, just like in Airplane!


  • Now that you know what the letters and numbers mean, let's look at some signs.

(Photo and sign from Astronics Corporation)

  • This is our sign from earlier.  Now we know that B means "Taxiway Bravo" and B3 indicates a taxiway stub or connector or exit.  Anything in a black box with a yellow outline means "this is where you are."  So this sign means "You are on Taxiway Bravo. Taxiway stub Bravo three is to the right."

(Photo and sign from Astronics Corporation)
  • Here's another one. This means "You are on Taxiway Alpha.  Taxiway Foxtrot is to the left or angled to the right."

(Image from Avery Dennison)

  • Let's try a little more complicated one.  This one means, You are on Taxiway Hotel 3, Taxiway Charlie is to the left, Taxiway stub Charlie two is angled to the upper right, and more of Taxiway Charlie is to the right.
  • The red circle with the white line through it means "CLOSED."  This sign seems to be saying a little too softly that Taxiway stub Charlie two is closed, but that's what it means.  
  • (I think in this case, Avery Dennison, a label-making company, is saying you could put one of our  temporary "CLOSED" sticker on your runway signs.  Really, the airport should put up a giant CLOSED sign and they're also supposed to paint big red Xs on the ground before a closed section.)

This is what a CLOSED, or NO-ENTRY sign should look like. Either this or a gigantic X. Big and obvious. No subtlety. 
(Image from the Aircraft Owners and Pilots Association

  • Those yellow signs are the kinds you see most often. Taxiway Alpha's exit is this way, etc.  Now that you've got those down, you'll be able to interpret most of the signs along the taxiways that you'll see from your airplane window.
  • But there may be other signs in other colors and letters.  What about those?

(Image from Holland Aviation)

  • By now you know the part in the black box means "You are currently on Taxiway stub Sierra six."  The stuff on the right you might guess indicates a runway named either "two four or zero six." You are correct about that, but since it's in red, it also means a whole other thing.
  • Red signs mean "stop" or "holding position."  This means the plane has to stop right here and wait until it gets the go-ahead from air traffic control to proceed onto the runway.  There will also be some yellow & black markings like crazy on the pavement next to the sign.  The plane is absolutely not to cross those yellow and black lines at all until the pilot gets the OK.

(Photo from Airchive)

  • What about this one?  It's a red sign, so you know it means stop, but there are no numbers on it, only the letters ILS.  That can't mean a taxiway, right?
  • Right.  ILS stands for Instrument Landing System.  This is the signalling system used by air traffic control to give pilots precise information about taking off from a runway, or landing on it.  The red ILS sign means this is a critical ILS zone, and "stop here and wait or you will interfere with ILS signals being given to planes taking off or landing on this runway."

(Image from the Aircraft Owners and Pilots Association)  

  • You might also see a red sign with two runway numbers followed by the letters APCH.  That stands for "Approach."  Like the ILS sign, this means you've entered the approach for a particular runway (runway 15, in this case), and you must wait here so you don't interfere with the ILS signals for incoming planes.

(Photo from Air News Times)

  • This image is kind of dark, but anyway, what does FBO mean?  That's not a taxiway either, right?
  • Right.  FBO means "Fixed-base operator."  It's basically the gas station for airplanes.  FBOs are typically businesses that operate independently of the airport -- Chevron, or Philips 66, or some other gas company -- but that serve airplanes at the airport.  They provide fuel for the planes, and they also may provide maintenance services, hangars, parking, equipment rental, and so on.  They are used most often by people who fly their own planes.

(Image from the Aircraft Owners and Pilots Association

  • This one you don't see very often, but MIL means a military installation is that way.
  • I think that about covers it.  Thank you for flying with the Daily Apple today.  Enjoy your destination.

FAA, Airport Marking Aids and Signs
FAA Engineering Brief No. 89, Taxiway Nomenclature Convention
Jim Sweeney, The Short Course: Airport Signs
Aircraft Owners and Pilots Association, Airport Signs and Markings
Nevada DOT, AOPA's Airports Signage & Markings (this uses the terms runways and taxiways interchangeably, which is very confusing)
AOPA's runway flash cards
Bangalore Aviation, Airport runways: All you wanted to know but were afraid to ask
Sploid on Gizmodo, This is what all the signs and symbols at the airport runway mean
Alpha Bravo

Monday, August 4, 2014

Apple #680: Henna Tattoos

This weekend at the state fair, I got a henna tattoo.

I went for a simple $8 design of a sun. The tattoo artist offered to extend it so it goes up my finger. I said OK by me.
(Photo by the Apple Lady)

Naturally, I asked the woman who gave me the tattoo all sorts of questions about it.  And again naturally, I have still more questions.  So here follows some of the things she told me mixed in with some of the things I looked up and have learned since.

What Is Henna?

  • Henna is a dye made from the ground-up leaves of the henna plant (Lawsonia inermis).  
  • It's sometimes also referred to as mehndi or mehandi or mendhi.

The henna plant is a pretty non-descript looking shrub.
(Photo from Sailu's Kitchen)

  • The plant is a flowering shrub that grows in all sorts of places, including the US and Australia, but it's most prevalent in the dry, arid regions in northern Africa, India, and the Middle East, and it also grows in Southeast Asia.
  • The leaves themselves won't stain anything; you have to crush them or grind them up before they will work as a dye. Most people make their henna dye from powdered henna.
  • Henna has been used as a dye for both hair and skin for centuries in several different cultures & religions in the areas where it grows.
  • Though people of Muslim, Hindi, Jewish, and other faiths have all used henna, they all generally consider that henna tattoos mean some sort of good luck or blessing. 

Traditional bridal mehndi -- henna tattoo on the hands & wrists prior to a marriage, here, on a bride from India.
(Photo from Sameera Threading)

Why it's Usually Brown, and Why on the Hands & Feet

  • Traditionally in most of these cultures, women's hands or feet, or both, were tattooed before a wedding as a way to invoke good luck for the bride or the marriage.  But now lots of people get henna tattoos for lots of purposes.
  • It takes a while for the henna stain to sink into the skin.  So you don't know right away how dark the tattoo will be.  The stain can range from tan to light brown to auburn to dark brown.  
  • What color the tattoo becomes depends on the person's skin, where on the body the tattoo is applied (some areas take up the stain better than others), how much henna is present in the stain mixture, whether the henna artist has used some form of mild acid like lemon juice or vinegar as an adjuvant, etc. 
  • Because the color of the stain varies from one person to another and from one application to another, the darkness of the tattoo is consider to signify the extent of the good luck. In other words, the darker the henna tattoo, the better your luck will be.  So the theory goes. 
  • Most henna tattoos are put on the hands and feet.  This is because the skin here tends to be thicker, so it will absorb more of the henna, and the resulting tattoo looks darker than it would elsewhere.  
  • Back of the hand and top of the feet works best because it's easier to keep from disturbing the henna paste as it dries and interrupting the process by which the paste stains your skin.  But people do put henna tattoos in lots of places--palms, shoulders, calves, bellies, etc.

This henna tattoo starts on the fingers, descends down the palm, and onto the wrist. You can see how the tattoo is darker on the fingers and palm than it is on the wrist. This is because the skin on the wrist is thinner and doesn't take up the stain as well as on the hand.
(Photo from Ohio Body Art)

What It's Made of

  • Most henna artists mix the powder into a paste. Typical ingredients include:
    • henna powder
    • black tea or coffee
    • lemon juice or lime juice or orange juice or vinegar (mild citric or acetic acid)
    • sometimes the lemon juice etc. is mixed with sugar
  • That's it. People say the resulting paste feels like toothpaste.  In my very limited experience, the paste that was put on me felt smoother even than toothpaste. More like gel toothpaste.
  • The henna plant is not toxic, and neither are any of those above ingredients. (The situation is a little different for "black" henna, but I'll get to that in a bit.)
  • The paste is applied to your skin, usually through a tiny little tube, sort of like a minuscule cake decorating tip.  There are no needles, nothing is injected into your skin, it is not a painful experience at all. In fact, it's rather soothing. 

This applicator is like what my henna tattoo artist used.  Most of the applicator is a slender metal cone which tapers to a fine point with a hole in the end. At the top end of the applicator is essentially a plastic bag containing the henna paste. The artist squeezes the bag which makes the paste come out the tiny little hole at the bottom. The artist moves the applicator while squeezing out the paste. Often the artist makes very detailed designs and fine lines. I was pretty impressed with the delicacy of the skill.
(Photo from ehow)

This is another type of henna applicator. Here, instead of a little plastic bag, the receptacle that holds the paste is a plastic bottle.  The tip of the bottle is the very fine tube with a tiny hole at the end through which the henna paste emerges as it is squeezed out and applied to the skin.
(Photo from Wikimedia Commons)

  • Since nothing is injected into your skin, some people say it's technically not a tattoo. 
  • The stain sinks down into only the first few layers of your skin, all of which are dead skin cells.  As these skin cells are naturally worn away, so also will the henna tattoo. That's why it only lasts a couple of weeks. 

The Application Process

  • The paste goes on black.  You leave it on, allowing the paste to dry and so the stain has time to sink into your skin.

Henna paste being applied. Here you can see how it sits on top of the skin.
(Photo from White Ink Tattoo Center)

  • You'll want to let the paste dry for anywhere from 4-8 hours. The range of time depends on the mixture your artist is using, how hot & humid the weather is, if you've got lotion on your hands (or wherever the tattoo was applied), etc.
  • This means you won't want to wet your hand--or foot or wherever you got the tattoo--during that drying time. So this is why people tend to get their henna tattoo on their non-dominant hand. 
  • You'll also want to avoid brushing it against things, which will rub the paste off, or flexing and moving that part of your body very much. 
  • When the paste dries, it will flake off in bits.  Some of those bits got on my sheets and left faint brown stains. I washed my sheets right away and the stain came out, no problem.
  • After the dried paste flakes away, the brown stain on your skin will become visible.  Over the next day or two, the brown stain will continue to darken somewhat.
  • You'll still want to avoid washing the area that's been tattooed for about 24 hours.  After that, you can wash your hand, but you'll want to avoid any vigorous scrubbing.  The more scrubbing, the more of those dead skin cells you'll wash away, and the faster your tattoo will fade.

Process of a henna tattoo, from paste to no-paste to additional darkening.
(Image from New World Henna)

This is what the paste looks like as it's drying & flaking off -- kind of crusty.
(Photo from Cuded)

Some of the designs can be really elaborate.
(Photo from White Ink Tattoos Center)

Or even more elaborate. This person would have to keep from moving both of her hands for several hours in order for this tattoo to turn out properly.
(Photo from ehow)

Henna on feet & toes -- also very detailed.
(Photo from Lovetoknow Tattoos)

Some pregnant women get henna tattoos on their bellies--I suppose in hopes of giving good luck to their forthcoming babies.
(Photo from Pop Sugar)

This might be a cool idea for someone going through chemo.
(Photo from Best Tattoo Designs Ideas)

Black Henna

  • In most photos of henna tattoos online, the henna looks black. I'm going to assume that this is probably because the picture was taken right after the henna was applied, before the paste dried.
  • However, there is a thing people call black henna.  This type of henna leaves behind a much darker, blacker stain after the paste dries and flakes off.  
  • The ingredient that gets added to the henna that turns it black is a chemical called paraphenylenediamine, or p-phenylenediamine, or PPD.
  • PPD is a type of coal tar that's been used for many years in hair dye, especially for brunette & black dyes. 
  • Some people are allergic to PPD.  If you are allergic to PPD, you do not want this stuff to touch your skin. It is possible to develop an allergy to PPD after having been exposed to it over time. This is why the hair dye people want you to do a skin test before each self-dyeing session, to make sure you haven't developed a PPD allergy.
  • But since henna is used to dye hair as well as skin, people thought, why not add the PPD that we've been using in hair dye to the henna, to make it darker?
  • It turns out, this isn't such a hot idea because for those people who are allergic to PPD, they experience some pretty unpleasant results with the black henna tattoos.

You can see that this woman from Kuwait got a really beautiful henna tattoo. Except the henna that was used had PPD in it, and she turned out to be allergic to PPD. So her skin turned red and swelled up every place the black henna was applied.
(Photo from Evans et al., New England Journal of Medicine

  • Since it takes quite a few hours for the henna to soak into the skin, it can also take that long before people discover they are allergic to the PPD in black henna. So, often the artist using black henna does not know if one of his or her clients has had a bad reaction to the black henna.
  • The best thing to do, therefore, is to ask your henna artist if he or she uses black henna.  If you know you're allergic to PPD, ask if he or she would use the regular henna instead. 
  • If you get a black henna tattoo and then discover you're allergic because your hand is tingling and itching and swelling up like a beautifully decorated basketball, go to your doctor as soon as possible. Most likely, your doctor will prescribe some sort of steroid that will take down the swelling.
  • If the reaction and the swelling are severe, you could wind up with permanent pigmentation -- your temporary black henna tattoo would become permanent.
  • Even if you think you're not allergic to PPD, it's probably best to avoid the black henna.

Now I'll show you some more pictures of regular henna tattoos because there are a lot of really magnificent ones.

(Photo from Factortruth

(Photo from Henna Tattoo Body Art)

Foot henna
(Photo from Cuded)

Leg henna
(Photo from Cuded)

Some henna tattoo artists are also adding additional dyes to make the henna different colors.
(Photo from Tattoos Time)

I think this one wins the prize. This is a wedding henna tattoo, complete with all sorts of colors, glitter, and body art gems.
(Photo from Crafty Nitti)

Desdemona's Designs Ohio Body Art, FAQ
Henna Arts, Frequently Asked Questions
The Henna Page, Why doesn't henna stain last forever like a tattoo?
Henna Mehndi, How to Mix Henna? FAQs
FDA Consumer Information, Temporary Tattoos May Put You at Risk
Colby C. Evans, and John D. Fleming, Allergic Contact Dermatitis from a Henna Tattoo, The New England Journal of Medicine, 2008; 359:627

Monday, July 21, 2014

Apple #679: Pork Bellies and Bacon

Not long ago, I tried pork belly for the first time. 

The first -- and for many years the only -- time I heard of pork bellies was in the Dan Aykroyd/Eddie Murphy movie Trading Places (1983) -- which still holds up, by the way.

Never heard a whisper about pork bellies after that. But all of a sudden in the past five or six years, it seems every other Food Network show has some chef who makes pork belly at least once per episode and gets all excited and drooly-mouthed about it as if it's some incredible delicacy.  Especially on Top Chef.

Top Chef season 6 contestant Kevin Gillespie (the guy with red hair & beard who made pork about 90 ways)'s smoked pork belly with pickled apples and pureed peanut sauce.
(Photo from Food Gal)

In spite of all their enthusiasm,pork belly has never looked that appetizing to me because there's usually a big hunk of fat on top.

Pork belly, with the fat on top crispy.
(Photo from Simple Comfort Food)

But recently I was at a restaurant that had pork belly on the menu so I thought, what the heck, I'll try it and see what all the fuss is about.

It tasted like a pork chop with a lot of fat on top.

But I did suspect that pork bellies and bacon have something to do with each other, and that if you cut a pork belly vertically, you'd get a strip of bacon.  Was I correct?  What exactly is the relationship between pork bellies and bacon?

  • The short answer is yes, my guess was correct.  Bacon is sliced from the pork belly.  But let me back up a second and give you the whole low-down.
  • As you would suspect, the pork belly is cut from the belly of the pig.

Chart of cuts of pork from the pig.  The section marked Side is where the belly and the bacon come from.  Even though this chart calls it the "side," most people say the pork belly comes from -- you guessed it -- the belly.
(Chart from Sugar Mountain Farm)

Raw pork belly with the skin still on.  The Food Network described pork belly as "a fatty slab of meat."  Yup.
(Photo from A Knife's Work)

  • Once you've got a slab of pork belly, you can go in either of two directions.  You can either roast or fry the belly or otherwise make that your dish of choice.  Or you can transform the pork belly into none other than our good friend bacon!
  • Bacon is pork belly that has been cured so it won't go bad, smoked, and then sliced into the familiar slices we all know and love.
  • Curing means you coat it in a ton of salt.  This is true of any meat, but with the pork belly you need an especially large boatload of salt.  This is because pork belly tends to go bad in a hurry.  Unsalted, pork belly would turn rancid in about 5 days.  So for the amount that's cut off the end there, you'd probably need around 3 cups of salt.
  • Plus you would add some sugar.  This is to help combat the saltiness and to add flavor. One guy recommends brown sugar.  Someone else recommends maple syrup.  Still another says to use honey.
  • You'd also want to add any other kinds of spices or flavors -- black pepper, garlic, rosemary, bay leaves, whatever strikes your fancy.
  • Another guy recommends adding just a touch of a preservation called saltpeter.  People are afraid of it because it's in things like gunpowder, but lots of green vegetable naturally contain more saltpeter than you'd be adding to your pork belly/bacon.  
  • If you don't use the saltpeter, you might use pink curing salt, which is sodium nitrite.  This ingredient helps to prevent botulism, and the pink helps turn the meat the nice red color we associate with deliciousness, and it also does improve the flavor to give you that deliciousness that the color promises.  
  • Yes, people have health concerns about sodium nitrite (or its precursor, sodium nitrate).  
In general, the American Medical Association has found that the concentrations of nitrites in normal quantities of preserved meats aren't sufficient to cause cancer. However, they also report that nitrites lead to formation of modified hemoglobin proteins, [which] can lead to cellular oxygen deficiencies. [from Livestrong]

Pork belly rubbed with the cure -- in this case, curing salt, kosher salt, dark brown sugar, black pepper
(Photo from Pork Drunk)
  • Once you've got your pork belly all salted & flavored up, wrap it snugly in plastic and put it in your refrigerator for about 7 days.
  • When you take it out and unwrap it, you will discover it will have formed a flabby soggy looking whitish layer on top.  This is called the pellicle and, yucky-looking though it may be, its appearance means you've done everything properly do this point, and it also helps seal in flavor and acts as a protective layer during the smoking.  Which comes next.
  • Some people buy or own a smoker and they stick their cured pork belly/almost bacon in there.  Or if you have one of those barbecue drums, you could use that.  Or you could use your regular old oven, but the flavor would not be as good. Because you would not really be smoking it.
  • You want the temperature in your smoker/grill/BBQ thing to be on the low side, around 200 degrees, but really smoky.  One guy recommends using half the coals you normally wood and adding wood that's been soaked in water for a little while so it will smoke a lot.  Of course the type of wood you choose will make a difference too.  Fruit woods tend to smoke a lot, as does hickory.  Which is why you often hear of hickory-smoked bacon, for example.
  • When you take your cured pork belly out of the smoker/BBQ/oven, it will look dang near like the bacon you're used to seeing.  And that's because it has become bacon.  All you need to do is slice it, and you'll say, hey!  I know that meat!  That's bacon!

Home-made smoked bacon, from pork belly.
(Photo from

  • Some people say to refrigerate for a while before slicing; others say slice and then refrigerate or fry it up as soon as you want to eat it.
  • Oh, and pancetta is essentially the same thing.  You take a pork belly, cure it, & smoke it. The difference is you use a specific recipe of spices in your cure rub.

Here are some recipes in detail:

Home-cured bacon, with spices still on top, prior to slicing.
(Photo from TasteFood)

Give it a try.  Let us know how your bacon turns out.

Oh, and by the way, pork bellies haven't been traded as a futures commodity since 2011.  Which may seem like a mistake because their fortunes have really taken off.  But actually this is why they're no longer traded.  The bellies don't get frozen & stored for later use, which is what made them ideal as a futures commodity.  Now, bacon & the pork bellies themselves are so in demand, they're eaten all year round.  Paradoxically, there's no longer a future in 'em. Har har.

Some futures traders lament their passing from the trading floor.  Apparently, pork bellies were a commodity for the most hard-core trader.  They could make you or break you.
There was the balding trader whose wig was seen as a gauge of the market’s volatility; on the craziest days, the wig’s part ran ear to ear, [Chicago Mercantile Exchange futures reporter Gary] Wilhelmi recalled. There was the analyst who died right there. “Bellies killed him,” Mr. Wilhelmi said. [from the New York Times]

Photo from the day the Chicago Mercantile Exchange began trading pork bellies -- September 18, 1961.  It was a good 50 years.
(Photo sourced from The '60s at 50)

Seattle Met, Bacon vs. Pork Belly, March 2, 2012
Food Network, Pork Belly Ribs and Bacon Guide
Sugar Mountain Farm, What Good is a Pig: Cuts of Pork, Nose-to-Tail, April 4, 2014
Cool Material, How to Make Bacon from Scratch
The Guardian, The secrets of home-curing your own bacon, March 16, 2011
A Knife's Work, Roasted Pork Belly
Jacob Burton, Difference between Sodium Nitrite, Nitrate, & Pink Curing Salt
Livestrong, Sodium Nitrate vs. Sodium Nitrite, October 21, 2013
Investopedia, Commodities: Pork Bellies and Pork Bellies: Definition
Trade in Pork Bellies Comes to an End, but the Lore Lives, The New York Times, July 30, 2011

Monday, July 14, 2014

Apple #678: Does Hair Dye Make Your Hair Fall Out?

Most of my Daily Apples start when I encounter some sort of question I don't know the answer to.  I look stuff up online, and I post what I find here.  One of my goals is to demonstrate that you can find the answer to just about any question on these here Internets, if you take a few minutes to run a few Google searches.  Now that pretty much everybody has a smart phone, you're all starting to figure that out.

But in some cases, these here Internets don't have all the answers.  I know, you Internet lovers are gasping in disbelief.  But it is true.  Sometimes the best way to learn about something is to experience it.  The answer to today's topic, can hair dye make your hair fall out, comes to you courtesy of your Apple Lady's personal experience.

This is actually a home hair coloring DON'T.
(Photo from SheKnows)

I'll give you the answer first, and then I'll give you some more information.  If you're interested, you can read on.  Or you can just get the answer and move along.

  • Yes, hair dye can make your hair fall out.  But only if it touches (and burns) your scalp.
  • One little spelling/grammar thing.  People, you are not "dying" your hair.  You are "dyeing" it.  Dying is the process of going down that dark road to death.  Dyeing is the process of coloring.  OK?  
  • And actually, we want to find out how to dye our hair without dying it.  If you get my pun.

Knowledge by Experience

  • Here's how I learned the truth about hair dye and hair loss:
  • For a while I had my hair professionally colored, but my hairdresser left a very thin strip along the part that wasn't colored.  After several sessions when this was still the case I thought, What the heck am I paying him all this money for if he doesn't even color the roots?  I'll do this myself.
  • So I started coloring my hair myself.  So much less expensive!  Plus, I made sure to put the dye as close to the scalp as possible.  No more differently colored roots!
  • Rinsing out the color afterward, I noticed more strands than usual coming away in my hands.  Not a ton more, but enough to be noticeable.  Slightly disturbing and not ideal, but not enough to freak me out.
  • But by the third or fourth time I did it myself, I was really putting the color close to the scalp.  Get it all down in there, I thought.  We don't want any of that undesirable shade (OK, gray) to show up any sooner than necessary.  I even kind of scrubbed it in at the temples.
  • Rinsing out the color that time, egad, practically buckets of hair came away in my hands.  Not, like, in giant bunches, but six & eight & ten strands at once, again and again and again.  Combing my hair afterwards, still a ton of hair coming away.  One and two days later, still, a ton of hair coming away in my comb and my brush, and even just when running my hand through my hair.  THAT was enough to freak me out.

This is about the level of hair loss at that time.  Maybe not even quite as much as this.  But enough to be upsetting.
(Image from

  • I looked up all sorts of things online and I found out that there's a chemical in some (OK, most) hair colors that can give you "adverse reactions" including making your hair fall out, or giving you an allergic rash, etc.
  • That chemical is paraphenylenediamine, sometimes abbreviated P-Phenylenediamine, or PPD.  
    • IMPORTANT NOTE:  At the time, I thought it was the PPD that was making my hair fall out, but it turns out, that only happens if you have an allergic reaction to it.  That's why the hair color box tells you to test the color on your skin first, before applying.  This test is to see if you are allergic to the PPD.  I didn't have that skin reaction, so the PPD wasn't actually the problem.  But for a while, I assumed it was. 

This is the amount of hair loss you could experience if you are allergic to PPD.
(Photo from Ishida et al., ISRN Dermatology)

  • I checked the ingredients on the box of hair color I'd been using and sure enough, that giant para-blahblah word was in the list.  The next time I went to the store, I looked at other brands of hair color, and they pretty much all had that ingredient.  So I thought, Well, so much for coloring my hair by myself.
  • So I went back to my hairdresser.  I assumed he was using some sort of "professional" hair color that wouldn't have that bad old PPD in it.  I told him what I'd read online, and when I mentioned this chemical, he picked up a box of the stuff he uses and frowned at it.  He said, "So, you're allergic to this chemical, and I shouldn't use hair color that has that in it?"
  • OK, now, here comes what's known as a "human moment."  I so wanted my hair to be colored that, even though I suspected his hair color had the PPD in it, and even though I suspected that the PPD would make my hair fall out, I told him it was fine, don't worry about it, go ahead.  I wanted my hair to be colored, even if that meant a good deal of it would fall out.  Go figure.
  • But there is actually a logic to me telling him to go ahead.  Which is that after he colored my hair a number of times before, there hadn't been much hair loss at all.  In fact, I noticed no difference between the day after getting my hair colored by him and any other day's normal hair shedding.  You know, a strand or two here & there.  No big deal at all.
  • So this left one other possible explanation for my hair shedding episode.  I said to my hairdresser, "So, do you avoid putting the hair color all the way to the scalp on purpose?"
  • "Yes," he said.  He explained that this keeps the different colors from bleeding into each other, and it also protects your scalp and the root of the hair from being damaged.
  • If I'd just asked him the question from the get-go, that would have saved me so much time.

Ignoring the fact that they are making this poor woman's hair striped, notice how they've left a bit of hair NOT colored up near the part. This helps keep your hair from being damaged and breaking at the scalp or falling out.
(Photo from BoldSky)

Again, notice how the foil doesn't actually go all the way up to the scalp but stops a little bit below the scalp. You may not be using foils at home, but you can be sure to apply the color a bit away from the scalp.
(Photo from 7YearsYounger)

This is what you DON'T want to do.  You don't want to inject the color right down into your scalp.  These squeeze bottles don't actually give you much control over where the color goes.  It will work better if you squeeze the color into a plastic dish of some kind and use a little brush to apply the color.  Clairol's Nice 'n' Easy Root Touch-Up is really cheap--about $4.50 at the grocery store--and it comes with a brush.  The color has lots of ammonia and is pretty harsh after more than a couple uses.  But it's a cheap way to get a coloring brush that you can rinse out and use again.
(Photo from SheKnows

  • Since then, I've looked up this question a couple other times, trying the search a few different ways to see what other responses come up.  Because all the aesthetician/cosmetician/professional hair care people insist that no, hair dye does not make your hair fall out.  But regular people like you and me say, Well, actually, it seems like my hair is falling out.
  • After combing through (pun!) a number of comments on a few chat boards, I noticed a pattern.  People who said they'd put a ton of color on their hair, or let it soak in, or otherwise put it all the way on their scalp--these were the people saying they were experiencing episodes of "shedding": tons of hair falling out over a period of a few days to a week.
  • So I took a chance and went back to coloring my hair myself.  (I really can't afford the professional thing that often.)   I've been careful not to let the color touch my scalp, though it is hard to keep that from happening sometimes, and I have not had another shedding incident since.  Some extra hair still does come away during the post-coloring rinse, but nowhere near as much as before.
  • Thus, I call the case solved: hair dye can make your hair fall out, but only if you let it touch your scalp.  Conversely, if you keep the hair dye from touching your scalp, you can reduce the possibility of hair loss quite a bit. 

More Facts I've Learned Since

  • So, most of your hair is dead.  That's why you can color it, cut it, curl it, blow it dry, and feel nothing.  As long as you confine the stuff you do to your hair to the dead part -- the shaft -- it's probably not going to have really serious effects.
  • But when you start messing around with the live part of the hair, then you're going to have problems.

A trusty diagram of ye olde hair follicle.  How many times have you seen diagrams like this?  But here's my point: look at all the activity going on under the surface of the skin.  There are oil (sebaceous) glands, there are blood vessels, there's the outer sheath, and there is the dermal papilla, better known as the bulb or the root.  All this stuff exists to keep your hair alive and growing.  Mess with this and your hair is not going to be happy.
(Diagram from Too Loop)

  • Hair naturally goes through a cycle of growth, falling out, and regrowth.  One strand of hair is in the growing phase for 4 to 6 years.  That's right, years!  Then it goes into a resting phase where nothing's happening.  Then a new bit of hair starts growing in the follicle under the old hair, pushing the old hair out and the cycle begins again.  
  • Normally anywhere from 50 to 150 strands of hair fall out per day as part of this cycle.  

Stages in a strand of hair's life: Growth, Transition, Resting, Falling Out/Regrowth.
(Diagram from Pure Aesthetics Pure Wellness)

  • When a stressor hits, the effects are felt in the follicle.  The results -- hair falling out -- can happen right away, or more often, within 2 to 3 months of the stressing event.
  • These kinds of stressors are usually major life things, like big changes in hormone levels, giving birth, very high fevers, diseases such as diabetes or lupus, severe dieting or anorexia, chemotherapy, radiation therapy, burns. 
  • Those big-time events literally make the hair fall out of the follicle. When the stressful thing goes away, the hair usually grows back eventually.
  • One of the experts who finally admitted that dyeing can adversely affect your hair says that dyeing the hair (or bleaching it or straightening it or giving it a perm) doesn't actually make the hair fall out, but rather breaks the hair off at or near the scalp, and then the root of the hair continues growing.  
  • I think she might be splitting hairs (another pun!).  I don't remember noticing the little bulb of white at the end of any of the hairs that have come out following a coloring incident, so maybe she's right.  Maybe the hair isn't actually falling out; it's only breaking off.  But either way, it's not what you want to happen.
  • The good news is that, once the color-treating process is over, even though that's when you discover that damage has occurred, the damage has actually stopped.  From that point on, the hair continues its growth process.
  • Hair grows about half an inch per month.  So within a couple of months, you can go back to being happy, smiling you.

(Photo by Ahoova on Flickr)

Ishida et al., "Severe Hair Loss of the Scalp due to Hair Dye Containing Para phenylenediamine," ISRN Dermatology, April 2011
Dr. Judith Reichman, Getting to the root of female hair loss, TODAY Health, August 2006, Can dying [sic] your hair cause hair loss?  
Susan Donaldson James, After Hair Loss at 11, Shame Ruins Woman's Singing Career, ABC News, April 3, 2013
Florida Center for Pediatric Dermatology, Does Hair Dye Make Your Hair Fall Out? Dr. Tace Rico Explains [they're talking about PPD and allergic reactions to it]
Linda DiProperzio, Women's Hair Loss: What Your Hair Stylist Might Not Be Telling You,