Music to My Ears

Walking around Julian, Roy O. West Library, or any other study space on campus, you are sure to see students working hard on their assignments while listening to music on their ipods or computers. Many students claim that the music helps them block out the surrounding distractions and concentrate on their work. Although students have a variety of musical interests, the common thought is that listening to classical music, such as Wolfgang Amadeus Mozart, is the best choice for studying. Research on the effect of listening to music, however, is not so clean cut.

On one hand, it would seem contradictory that dividing the brain’s function between two tasks, studying and listening to music, would provide an improvement to having the brain focus solely on studying. On the other hand, listening to music may stimulate the brain and enhance the student’s ability to study.

As it turns out, it may depend on how often you listen to music when you study. A study done at Bradley University gave reading comprehension tests to 16 male and 16 female college students. Half of each gender were given the test in a quiet setting, while the other half took the test with music of their choosing (many previous tests did not allow subjects to choose their music). The subjects read the passage for 10 minutes and then answered  5 questions without looking back at the reading. The mean reading comprehension score in the music condition for maIes was 6.9 and for females, 6.6. In the no-music condition, mean scores for males and females were 6.6 and 8.6, respectively. While it appears that the music had no major effect on the males and a large effect on the females, the results also showed that the frequency that the students study with music was also significant. Among females, two reported that they frequently studied to music, 4 said occasionally, and 10 reported never. Of the male subjects, 5 reported frequently studying to music, 6 said occasionally, and 5 reported never. Thus, females studied to music less often than did males. The distracting effect that the music had on the females studied can be explained by the fact that they were not used to studying with music.

A more recent study at the University of Wales Institute in Cardiff, United Kingdom, suggests that music may actually hurt your studying if you are trying to memorize and ordered list, such as numbers, facts, or dates. Participants were tested under various listening conditions: quiet, music that they’d said they liked, music that they’d said they didn’t like, a voice repeating the number three, and a voice reciting random single-digit numbers. They then instructed 25 participants between ages 18 and 30 try to memorize, and later recall, a list of letters in order. The study found that participants performed worst while listening to music, regardless of whether they liked that music, and to the speech of random numbers. They did the best in the quiet and while listening to the repeated “three.” The researchers hypothesized that your brain might get thrown off it’s attempt to memorize a sequence by the changing words and notes in a song. This study, however, does not completely contradict previous studies that show music’s benefit. It simply points out that there may be limitations on the types of studying that are enhanced by listening to music.

But what is actually happening in the brain that would cause the positive or negative effect of listening to music while studying. Recent research using functional magnetic resonance imaging, or fMRI, allows scientists to see what the brain is doing and take pictures and videos of its activity. Using this technology, a research team from the Stanford University School of Medicine research team showed that music engages the areas of the brain involved with paying attention, making predictions and updating the event in memory. A link to the video is here: http://med.stanford.edu/news_releases/2007/july/music.htmlSubjects listened to short symphonies by 18th century composers while undergoing the fMRI to image their brain. What surprised them was that the peak brain activity came during the short time period in between musical movements.

So what does all this research mean, and how does it apply to you?

First, if you currently listen to music while you study, you can continue. If, however, you are thinking starting to listen to music for the first time, you may want to stop and rethink. Starting this new activity during your studying may distract you until you become used to it.

Second, it depends on the type of studying you are doing. If you are trying to memorize a list, ordered process, or the digits of pi, listening to music will hinder your studying.

Third, to increase your brain activity, only listen to the transitions in between songs on your ipod. This suggestion may not be particle, but you can try it if you want.

References:

Baker, M. “Music moves brain to pay attention, Stanford study finds.” Web. 30 Nov. 2011. http://med.stanford.edu/news_releases/2007/july/music.html

Landau, E. “Music may harm your studying, study says.” web. 30 Nov. 2011. http://thechart.blogs.cnn.com/2010/07/27/music-may-harm-your-studying-study-says/

Etaugh, C. and Michals, D. “Effects on Reading Comprehension of Preferred Music and Frequency of Studying to Music.” Perceptual and  Motor Skills,  1975, 41 , 553-554.

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Trash Talk

With all the recent talk of being “green”, many people have begun to make small changes to do their part. Living on my own I have vowed the same. Since I live in a duplex, without a yard, I am unable to compost so I have begun using my garbage disposal religiously.

Have you ever thought about how your garbage disposal works? Well, neither had I. Most people view their garbage disposals as being mysterious, you flip a switch and it works. That’s all most people care to know, though how a garbage disposals works is actually quite simple.

It is commonly thought that a garbage disposal works like a blender, with spinning blades chopping and breaking down the food. In reality disposals work in a different way and there are NO blades involved. Instead, impellers (or lugs) mounted on a spinning plate use centrifugal force, at a speed of almost 2,000 RPM, to continuously force food waste particles against a sharp-toothed inner wall. The wall breaks down the food waste into very fine particles, practically liquefying them. This process is most commonly interrupted, causing a jam, when the food placed in the disposal is either too large or too firm for the machine to handle. In these instances, the food will usually fall beneath the plate where it cannot be broken down properly. Keeping this in mind, large or firm pieces of food should not be placed directly into the disposal, but should first be broken down by hand into a workable size. Once pulverized, the running water flushes the particles through the inner wall, out of the disposer, and into your wastewater pipe. From there it flows into your septic system or to the wastewater treatment plant.

There are two common types of garbage disposals available that differ slightly from one another; continuous feed and batch feed. A continuous feed disposal operates, once switched on, by feeding food and water from the spinning plate to the inner wall and then finally to the drainage pipe. Batch feed disposals work in a similar way, except for the fact that a stopper is placed in the disposal. After loading a batch feed disposal, the stopper activates a switch which turns it on. Continuous feed disposals are considered to be more user-friendly, and are therefore more common, than batch feed disposals.

I hope you enjoyed learning about a little bit about your garbage disposal, but if you’re craving a bit more, here are some fun facts…
• John W. Hammes invented the garbage disposal in 1927 for his wife (apparently she didn’t want a vacuum cleaner). He spent eleven years refining his invention before starting his own garbage disposal business. The name of his company? The In-Sink-Erator Manufacturing Company.
• In nations with ready access to water and an industrial base, such as the United States, garbage disposals are common fixtures.
• In the US approximately 50% of homes had garbage disposal units in2009, compared with only 6% in the UK.
• Garbage Disposal Energy usage is not high; typically 500 to 1500 watts of power are used. This is comparable to an electric iron, but only for a very short time. Per year, this totals to approximately 3-4 kilowatt hours of electricity per household. Daily water usage varies, but is typically one gallon of water per person per day, comparable to an additional toilet flush.
• Food scraps range from 10 – 20% of household waste, and can be a problematic component of municipal waste. Burned in waste-to-energy facilities, the high water-content of food scraps does not generate energy; buried in landfills, food scraps decompose and generate methane gas, which is considered to be a potent greenhouse gas.
• The premise behind the proper use of a disposal is to effectively regard food scraps as liquid (averaging 70% water, like human waste), and utilize existing infrastructure (underground sewers and wastewater treatment plants) for its management. Modern wastewater plants are effective at processing organic solids into fertilizer products (known as biosolids), with advanced facilities also capturing methane for energy production.

References
Formisano, Bob. “Anatomy of a Garbage Disposal.” Home Repair. About.com. Web. 26 Nov. 2011. .
“Garbage Disposal: Facts, Discussion Forum, and Encyclopedia Article.” AbsoluteAstronomy.com. Web. 27 Nov. 2011. .
In-Sink-Erator Staff. “How Garbage Disposals Work.” InSinkErator. Web. 26 Nov. 2011. .
Larsen, Kurt. “How A Garbage Disposal Works.” Home & Garden Ideas. The Writers Network, 24 Feb. 2011. Web. 26 Nov. 2011. .
Vandervort, Don. “Home Tips : How a Garbage Disposal Works.” Home Tips. Web. 26 Nov. 2011. .

Food Cravings and what those foods do to your brain!

Ever find yourself staring at that delicious chocolate cake or pumpkin pie on the shelf and with your mouth watering just at the sight of it? Then you know how craving food feels like.

Scientists define food craving as the intense desire for a very specific food and your willingness to go out of your way to receive it. A lot of us blame ourselves for giving into those cravings “letting go” by indulging into something either sweet or very fatty, but there are many scientific facts that now allow us to understand why those foods are so tempting.

Many questions may arise when you think about food craving and I will attempt to answer a couple with this post, starting with: What types of foods do we crave and why?

Many of us think of craving as the desire for something sweet, but scientists at Tufts University did a wide study, where they found that even though sugary foods are preferred, fats are not left behind. The craving for a specific type of food differs on a personal basis, but we mainly tend to go for foods that are very calorie dense and tend to go for a combination of carbohydrate and fat rich food. An interesting thing that those researchers also found is that the craving intensity did not depend on body mass index of the people tested. Lean people experienced just as much craving as obese ones, but the obese ones would need bigger amount of food to satiate that craving.

So why do we have those cravings is the next most logical question? The only theory that holds strong logic in this case is derived from our evolutionary history. Any species needs nutrition to survive and through the years nutrition has not been as readily available as it is now. Thus, it would be more beneficial for our predecessors to find food that is highly packed with those vital calories they would need. So in the idea of “survival of the fittest”, the fit specimen would be the ones able to find enough calories to survive, thus the ones that seek them most avidly are the ones that find them. On the other hand, that doesn’t mean that you can blame your ancestors for all your cravings, it’s partly your fault!

Now that we know that we can partly blame evolution this leads us to two more questions: What exactly happens that causes us to crave and why are we in part to blame for cravings?

Researchers at Johns Hopkins Medical School have found that there are specific centers that light up in the brain on a functional MRI (magnetic resonance imaging) when people think about foods they crave. The fact that those sections light up, shows they are activated. The more interesting thing is that those sections don’t activate when we think about low calorie food, but also that those are the same parts of the brain connected to drug addiction.

The amygdale, hypocampus and nucleus accumbens are strongly associated centers of pleasure. Those are the same places that drugs activate and those are the same places activated by the sight or thought of craved foods. Through those images the researchers also found something even more fascinating: when lean people consume craved food those sections light up more strongly than in obese people. Lesson learned – leaner people experience more satisfaction from the food than obese people, who have to consume more to receive the same satisfaction.

So why should we in part blame ourselves for our cravings? The more often you indulge on these “craved” foods you train your brain to get accustomed to them, a process called “sensitization.” The more accustomed your brain is, the less satisfaction you receive from eating that food you craved. The less satisfaction you get the bigger amount you crave. It is a vicious cycle that leads into obesity and depression very fast. Food addiction is real and it is not to be undermined.

To leave you on a positive note all of this is to just remind you that “craving” food is absolutely normal and 96% of people experience it. The difference is that if you indulge on that craving frequently it will become stronger. The good side is that like any addiction it can be overcome. As long as you stick to a good diet, it is estimated that you can go back to the same amount of craving as a “lean” person within 3-6 months. Hope that helps!

Sources:

Beaver, J., et. al. “Individual Differences in Reward Drive Predict Neural Responses to Images of Food.” Journal of Neuroscience. Vol. 26(19) Pg:5160 –5166. May 10, 2006

Pelchat, M. et. al. “Images of desire: food-craving activation during fMRI.” NeuroImage. Vol. 23. Pg 1486-1493. 2004

Bryant, R., Dundes, L. “Fast food perceptions: A pilot study of college students in Spain and the United States.” Apetite. Vol 51. Pg. 327-330. 2008

Gilhooly C., et. al. “Food cravings and energy regulation: the characteristics of craved foods and their relationship with eating behaviors and weight change during 6 months of dietary energy restriction.” International Journal of Obesity. Vol 12. Pg 1849-58. 2007

Tufts University, Health Sciences. “Links Between Food Cravings, Types Of Cravings, And Weight Management.” ScienceDaily, 18 Jul. 2007. Web. 24 Nov. 2011


Dirty Mouth? The Science of Teeth Whitening

It seems that as we move further into the 21st century, Americans are using modern techniques to evade everyday responsibilities. Overweight people get liposuction to avoid exercise, singles use the internet to find their “soulmate,” and parents pick up fast food to avoid cooking and cleaning. Another example of this is teeth whitening. I admit, I have on occasion used teeth bleach, simply to whiten my teeth after years of braces, or to give my smile a like “pick-me-up.” However, there are people out there that depend on this process to replace teeth brushing. Sure, it seems harmless and an easy fix to not brushing your teeth twice per day, but what it really happening in your mouth? How are the chemicals in teeth bleach physically changing the color of your teeth? Is it harmful to whiten too often? Let’s explore the scientific processes behind a few different methods of teeth whitening…

First of all, what are teeth even made of? The somewhat translucent, exterior layer of the tooth is called “enamel,” which is made of a crystalline calcium phosphate (a mineral). Since it’s made of so much mineral, it is very strong yet brittle. The criss-crossing layer of minerals creates rod-shaped holes in the enamel, making is porous. The layer underneath the enamel is called “dentin,” which is made up of the same material as enamel in combination with water. It is yellowish in appearance, which causes some teeth to become yellow when they are not clean.

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After eating different types of food, another layer called the “pellicle” gradually starts to form on top of the enamel. This layer can be brushed away by a toothbrush or by a dentist who can scrape it off. However, the enamel is porous, so the pellicle (or stain) can get deep into the dentin after years of the pellicle sitting on the tooth. Bleaching agents in whiteners can get down into the dentin to remove these stains. Let’s take a closer look…

“Dentist Supervised” whitening involves the use of a gel that consists of a certain percentage (15-35%) of hydrogen peroxide coupled with the use of a UV light. The hydrogen peroxide, upon entering the tooth, releases “free radicals” to “oxidize” the stain beneath the enamel. Confused yet? It’s really very simple. A free radical is an atom, molecule, or ion with unpaired electrons. When something is oxidized, it loses electrons. Thus we can safely assume that the electrons in the organic compounds in the stain are being donated to those in the free radicals released by the bleach. This causes the degeneration of the stain, and thus the yellow color to disappear. Adding light to the equation accelerates this whitening process.  UV light is known to accelerate many chemical processes, including the oxidation of the stains in your teeth. So while you do have to sit with your mouth open and a light stuck in it for about 30 minutes to 1 hour, you’ll only have to go in once and you won’t have to keep bleach in your mouth for hours at a time.

As you all know, we can obviously also whiten our teeth at home. The difference here is the use of a lower concentrated (10-20%) carbamide peroxide gel (and more time consumption, unfortunately). Carbamide must be broken down into hydrogen peroxide during a separated chemical reaction first during the chemical reaction, which is why it takes longer than if you went to the dentist. Using either custom-made “trays” or over-the-counter “strips.” You can eventually achieve similar results to those from the dentist’s office. You must be careful, however, not to get the gel onto your gums, which are made of soft connective tissue. Leaving hydrogen peroxide on them for too long can causes burns, which will leave your mouth sensitive for a few days.

Hydrogen Peroxide

Carbamide Peroxide

So there you have it, a bleaching gel in combination with UV light causes a simple chemical reaction that removes stain below the enamel layer of teeth. So popular contrary belief, it is science, not magic that changes the color of your teeth. And even though you may be removing the stain, you are not removing permanent damage done to enamel by not brushing your teeth (I’m talking cavities, my friends).

References:

1. “The Chemistry Associated with Peroxide-Based Teeth Whiteners” http://www.dental-picture-show.com/teeth_bleaching/a3_teeth_whitening_science.html

2. “Teeth Whitening – How it Works and What it Costs” http://www.yourdentistryguide.com/teeth-whitening/

3. “Antioxidants and Free Radicals” http://www.rice.edu/~jenky/sports/antiox.html

4. “The Art and Science of Tooth Whitening” http://www.ncbi.nlm.nih.gov/pubmed/15828604

Easy Mac, Spaghettios, and left overs…What would we do without microwave ovens?

First off, who am I and why should you trust me?…

I am a senior biochemistry student at DePauw University in beautiful, small, middle of no-where Greencastle, IN. I am originally from Knoxville, Tennessee, so if you’d like you can imagine this post was written in a Southurn accint. My background is mostly in biochemistry, but as an aspiring med student I’ve also taken two semesters of physics. I did pretty well in those two semesters, and I’m confident I learned enough to research the basics of microwave physics and explain them to you here. I have also have an extensive history with microwavable food…I currently eat Lean Cusines and Campbell’s Soup on a regular basis while I’m at school…so I’d like to think you can trust me when I say I am a microwave expert of sorts.

Everyday when my brother and I came home from school he would open a can of Spaghettios, pop them in the microwave, and wait the 2 or 3 minutes until they were warm and ready to eat. When I was younger I just inherently knew that if you put something in the microwave and turned it on for long enough the food would get warm, but how does a microwave oven actually heat up your food?

Microwave ovens actually use microwaves- a form of electromagnetic radio wave to heat food. Electromagnetic radiation is a form of energy that has both electric and magnetic field components and exhibits wave-like behavior as it travels through space (4). Radio waves have the longest wavelength and the lowest frequency in the electromagnetic spectrum (seen below), making them the lowest energy EM wave based on the Plank-Einstein relationship (E = hc/λ) which says the energy of an electromagnetic wave is directly proportional to the Planck Constant (h) and the speed of light (c) but indirectly proportional to wavelength (4).

In the case of microwave ovens, the frequency of radio wave usually used is about 2,500 megahertz (4). Interestingly, microwaves at this frequency are absorbed by water, fats and sugars and are not absorbed by most plastics, glass or ceramics. As the water, fats, and sugars in your Spaghetios or Pop-Tart absorb the microwaves they heat up by a process called “dielectric heating.” The molecules are dipoles, meaning they have a positive and negative charge on opposite ends. The dipoles begin to spin as they try to align themselves with the alternating electric field of the microwaves, causing them to rub together and create heat (3). The heat produced by the the water, fat, and sugar molecules in your food rubbing together begins to heat the molecules around them and, essentially, to cook your food! The length of time required to cook your food, therefore, depends on its water, fat, and sugar content in relation to its size.

…So, where do the microwaves come from? The microwaves are generated by a magnetron within the oven. Magnetrons were invented in 1921 and then vastly improved in the 1940s (2). The physics of a magnetron is a little beyond the grasp of this blog, but in layman’s terms it is essentially a tube that moves electrons through a magnetic field which causes the electron path to curve and create oscillating microwaves (2).

The microwaves are then corralled into the cooking box by the waveguide where they bounce around, reflected by the metal of the box, until they are absorbed by your food. Microwaves are a common household object around the world. We use them to heat up left-overs, cook microwave dinners, and to pop popcorn before we sit down to watch a movie. I hope you enjoyed learning about a little bit about the science behind these household marvels, but in case you’re craving a little bit more knowledge, here are some fun facts…

  • Microwaves cook your food from the inside out, as opposed to a conventional oven which cooks food from the outside in by the process of convection. This is why Hot Pockets have a little metal casing around them which allows heat to be reflected back at its surface creating a crust! (1)
  • Microwaves aren’t nearly as efficient at cooking frozen foods because the molecules are not free to rotate. (3)
  • As of 1971 only about 1% of American homes had a microwave. That number rose to 25% by 1986, and as of 2009 90% of American households had a microwave.
  • Microwaves convert Vitamin B12, an essential vitamin predominantly found in meat, to an inactive form. (3)
  • However, spinach retains almost all of its folate when cooked in a microwave, but loses approximately 80% when it is cooked on a normal stove. (3)
  • The first documented use of the term “microwave” was in 1931. It was used in a Telegraph and Telephone Journal, which said “When trials with wavelengths as low as 18 cm were made known, there was undisguised surprise that the problem of the micro-wave had been solved so soon.” (3)

References:

1. Brain, Marshall. “HowStuffWorks “Microwave Cooking”” HowStuffWorks “Home and Garden”2011. Web. 16 Nov. 2011. <http://home.howstuffworks.com/microwave2.htm&gt;

2. Gallawa, Carlton. “The Magnetron Used in Microwave Ovens: Structure and Operation.” Gallawa Family Web Site. 2008. Web. 16 Nov. 2011. <http://www.gallawa.com/microtech/magnetron.html&gt;.

3. “Why You Generally Shouldn’t Put Metals in the Microwave.” Today I Found Out: Why You Generally Shouldn’t Put Metals in the Microwave. Vacca Foeda, 2010. Web. 16 Nov. 2011. <http://www.todayifoundout.com/index.php/2010/08/why-you-generally-shouldnt-put-metals-in-the-microwave/&gt;.

4. Vollmer, Michael. “Physics of the Microwave Oven.” Physics Education 39.1 (2004): 74-81. Print.

Fishy Diets – What Are You Really Eating?

In 2007, several people in the US sat down to what they thought was a harmless dinner of monkfish. Little did they know that this particular Chinese import was actually a toxic puffer fish that had entered the country under the cover of a more innocuous name (1). This scare began to draw more attention to the regulation of the fish market and labs began to investigate whether this incident was an aberration or a frequent occurrence. In the United States, most consumers are completely trustworthy of food labels and believe that a misrepresentation of a food product is extremely rare or nonexistent. This year, multiple labs investigated this assumption and did not like what they saw. Some of these labs included associates of Oceana (an environmental group), Consumer Reports Magazine, private lab companies like ACGT, Inc, and the Food and Drug Administration (FDA). Their results showed a massive problem in our country’s seafood regulation.

Seafood is a staple food in cultures around the world. It is commonly considered a healthy alternative to many other food groups and there are multiple delicacies found in oceans, rivers, and ponds. The FDA recognizes 45 species-specific market names for fish (4) and retail companies must legally identify their fish with these market names. Unfortunately, it is believed that 20-25% of seafood samples throughout the world are actually mislabeled, oftentimes as a more expensive species (3). In fact, the FDA port inspections speculate that a third of seafood sold in the U.S. is mislabeled. One reason for this may be that 86% of seafood eaten in the U.S. is imported and only about 2% of these imports are inspected (2). This deception costs consumers millions of dollars each year when they are under the belief that they are actually buying a more expensive fish (1). It also may cause health problems similar to the toxic puffer fish or allow endangered fish to be sold illegally, thus enabling the decimation of certain species.

During the occurrence of the puffer fish incident in 2007, fish samples were verified through protein analysis, or isoelectric focusing (1). Each fish species contains slightly different proteins in its body and this test identified the proteins by their electric charge differences. This older test was limited by its inability to determine the accuracy of the sample’s identity if it had been processed or cooked because these processes affected protein structures. This rendered the test useless in many different circumstances. The next step in seafood regulation was to determine a more efficient and reliable way to regulate seafood.

So what is the new technique that was developed to identify these species? The answer is simple; scientists are now able to use a DNA barcode to identify different fish species. Every living organism has a DNA sequence that is unique and contains the individual’s genetic information. A single species will have individuals with varying DNA sequences, but there will exist certain genes in common that are only usually found in that particular species. A gene is a stretch of DNA that codes for a protein, so this basically analyzes the same information as the old test, but at an earlier stage. DNA is not as easily affected as proteins by any processing done to the fish. Comparing DNA barcodes is easy to do and relatively inexpensive. It compares the sample’s DNA to a known database and matches the sample to its correct species (1). There is currently a global effort to finish a Consortium for the Barcode of Life (CBOL), which is a sequence reference library for every species of fish on earth for the specific gene, cox1 (4). It currently contains the gene sequencings for cox1 in most seafood species. If a lab needs to identify a species, they are able to do so by comparing their sample’s DNA to this library. This analysis requires only a gram of the sample and is able to identify the sample whether it is raw, frozen, steamed, or deep-fried (1). In fact, DNA barcodes could be extremely helpful for the FDA in many cases of food-related illness or economic fraud investigations. In order to begin testing on a regular basis, the FDA recently installed DNA-sequencing equipment in nine of its laboratories across the country in order to decrease seafood substitutions. This technology will allow the United States to take the next step in food safety and help ensure that regulations are upheld in order to decrease economic fraud, harmful substitutions, and a great threat to endangered species.

This shows a comparison of genes (or stretches of DNA) in different tuna species. The rows indicate the genes being analyzed from the different species and the columns indicate the specific nucleotide being looked at. Nucleotides make up DNA similar to how atoms make up different molecules. Highlighted boxes show specific nucleotides that cause a gene to be unique for a single species.

Works Cited

1. “Specious Species: Fight against Seafood Fraud Enlists DNA Testing”. Scientific American. November 10, 2011. <http://www.scientificamerican.com/article.cfm?id=dna-testing-for-seafood-fraud&gt;

2. “Fake Fish: Experts Say Mislabeling of Seafood is Risky Business”. ABC News. May 27, 2011. <http://abcnews.go.com/US/fake-fish-experts-mislabeling-seafood-real-problem/story?id=13706266#.TsIE2XPb_fE&gt;

3. “Mystery fish: The label said red snapper, the lab said baloney”. Consumer Reports Magazine. December 2011. <http://www.consumerreports.org/cro/magazine-archive/2011/december/food/fake-fish/overview/index.htm&gt;

4. Lowenstein, Jacob H., George Amato, and Sergio-Orestis Kolokotronis. (2009) The Real maccoyii: Identifying Tuna Sushi with DNA Barcodes – Contrasting Characteristic Attributes and Genetic Distances. PLoS ONE 4:4-14.

Why Can’t I Breathe?

Environmental allergies are one of many ways allergies can inhibit our day-to-day lives. (http://www.allergydruginfo.com/images/allergy-medication.jpg)

Whether it is a runny nose, itchy eyes, or a skin rash, many of us have faced the systems of an allergic reaction at some point in our lives. They are a determining factor in the places we go, the pets we have, and even the food we eat. The Asthma and Allergy Foundation estimates that allergies affect 50 million Americans, making it the fifth leading chronic disease in the country. Despite the frequency of allergies in the population, few individuals really understand how allergies occur (1).

A healthy body’s immune system is set up to constantly identify invading pathogens by identification of self vs. non-self. While one definitely should not be upset that the body has this skill, things can become problematic when the body cannot differentiate what non-self entities are harmful or harmless. Allergies are induced when the body begins to strike against non-harmful entities (5).

The above picture describes the process of eliciting an allergic response. An allergen causes B cells to release IgE, which bonds to Mast cells or Basophils. When allergens interact with these antibodies, the cells they are attached to lyse and release chemicals that cause allergy symptoms. (http://microbiology2009.wikispaces.com/Histamines--What+They+Do+%26+What+Anti-Histamines+Do+to+Stop+Them)

When an allergy is induced, the body identifies an allergen, inducer of the allergic response, as an invader. An allergen may be anything individuals are exposed to in day to day life (2). In order to remove this invader, the body elicits a response to destroy it. T-cells and B-cells, two types of White Blood Cells, play an important role in eliciting this response. When these cells are presented with a foreign substance, T-cells either recruit more White Blood Cells or directly attack whatever invader is present. B-cells release antibodies, which are also engineered to fight off the specific invader. IgE is the antibody specifically associated with allergic reactions. It bonds to basophils and mast cells, eventually causing them to release their contents, including a protein named histamine (5).

Histamine influences the body by causing inflammation. When an area of the body is inflamed, blood vessels become less dense, allowing an increase in the number of blood cells able to enter the site of histamine release. This increase in blood cells causes swelling at the site of the allergic reaction (4). These additional blood cells may also trigger the allergic response, causing the reaction to become worse with continued exposure. Histamine also causes smooth muscle to contract (6), which leads to breathing difficulties frequently associated with an allergic reaction.

There are several ways a person may try to deal with allergies. Some simply try to avoid allergens that tend to cause an immune response. Sometimes, allergens cannot be avoided, so allergy treatment drugs are provided. One common way to treat allergies is to use anti-histamines, such as Claritin and Allegra. They work to inhibit the ability of histamine to bond with other molecules that cause the allergic response (4). In severe allergic reactions, some individuals require an epinephrine injection. Epinephrine causes blood vessels to contract, inhibiting the allergic response (3). In severe cases, immunotherapy may be used. Immunotherapy forces the patient to be exposed to the allergen that normally elicits a response. While it is not always effective, in some cases it causes the body to release IgG, a blocking antibody that improves a subject’s response to an allergen (5).

While some of these ways of dealing with allergies are achieving a reasonable amount of success with sufferers, a larger question remains. How do we prevent allergies from developing in the first place? Research from the University of Copenhagen claims allergies tend to develop more prevalently in individuals who are not exposed to many types of bacteria in the first six months of life (7). This is why infants born via cesarean section have a much higher tendency to develop allergies than those born naturally (7). Naturally born children are much more heavily exposed to the mother’s bacteria in the birthing process. Some researchers suggest this reasoning is also why children raised in rural environments are less prone to develop allergies.

Though we still have a lot that we may learn about allergies, the information we see indicates that an increase in allergies is being caused by modern medicine. By not allowing bacterial exposure early in life, we are forced to face alternate medical consequences. Hopefully, researchers will develop a fuller idea of how to prevent both illness and allergies, but, in the meantime, we are left to take our Claritin, fear our bees, and exhibit caution in the presence of peanuts.

Works Cited

1. “Allergies – PubMed Health.” Web. 09 Nov. 2011. <http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001815/>.

2. Cunha, John P. “Allergic Reaction Symptoms, Causes, Signs, Treatment and Prevention by EMedicineHealth.com.” EMedicine Health. Web. 09 Nov. 2011. <http://www.emedicinehealth.com/allergic_reaction/article_em.htm>.

3. “Epinephrine Injection: MedlinePlus Drug Information.” National Library of Medicine – National Institutes of Health. Web. 09 Nov. 2011. <http://www.nlm.nih.gov/medlineplus/druginfo/meds/a603002.html>.

4. “Histamine.” Biology @ Davidson. Web. 09 Nov. 2011. <http://www.bio.davidson.edu/courses/immunology/Students/spring2000/lamar/mfirp.htm>.

5. “HowStuffWorks “How Allergies Work”” HowStuffWorks “Science” Web. 09 Nov. 2011. <http://science.howstuffworks.com/environmental/life/human-biology/allergy.htm>.

6. Schmidt D, Ruehlmann E, Branscheid D, Magnussen H, Rabe KF.  1999 Aug.  Passive sensitization of human airways increases responsiveness to leukotriene C4.  European Respiratory Journal 14(2): 315-319.

7. Hans Bisgaard, Nan Li, Klaus Bonnelykke, Bo Lund Krogsgaard Chawes, Thomas Skov, Georg Paludan-Müller, Jakob Stokholm, Birgitte Smith, Karen Angeliki Krogfelt. 2011. Reduced diversity of the intestinal microbiota during infancy is associated with increased risk of allergic disease at school age. Journal of Allergy and Clinical Immunology 128 (3): 646 -652.