Monday, February 27, 2012

Survival of the sickest

On page 177 of Survival of the Sickest one of the study's authors, Dana Dolinoy states, "What is good in small amounts could be harmful in large amounts. We simply don't know the effects of literally hundreds of compounds that we intentionally or inadvertently ingest or encounter each day." I think that her statement is very true and I support it because we are told on a daily basis that certain things are bad for us, but then a couple months or years later we are told the opposite. Just like we mentioned in class about butter, first we were told that butter is bad for us and to use margarine instead, and now we are told that margarine is even worst and to go back to using butter. But I think as long as we limit our intakes of products, and portion them out accordingly, it is less harmless than consuming it in large amounts. I think that humans as a whole have a problem with consuming too much of one product, and not balancing out the good with the bad.

Another thing I found interesting is Dr. Sharon Moalem saying, "we don't know" throughout the book. One thing particularly, how little we know about possible epigenetic and maternal effects. Being a psych major I've learned a lot about the maternal effects on the baby, but I've never heard that my mothers genes will have an effect on my baby. Even though there is still complications and uncertainty with the data I find it very interesting that my mothers habits and environmental settings might have effects on my children, or that my genes can be carried to my granddaughter, through my daughter.

The Slavery Hypothesis

In Survival of the Sickest, Dr. Moalem mentions the idea of the Slavery Hypothesis in order to illustrate the mechanism of evolutionary medicine and its long term consequences. The Slavery Hypothesis is the idea that African-Americans have a predisposition for high blood pressure due to selection during the Middle Passage and ensuing enslavement. Dr. Clarence Grim hypothesized that slaves who survived the journey were likely to have been able to retain high levels of salt, as the death rate was high due to deprivation of food and water, as well as rampant illnesses that caused diarrhea and vomiting. Moalem does not mention that these claims are widely unsubstantiated. There is no proof of there being historical validity to the fact that Africa was salt-scarce and the statistics regarding this hypothesis lack supporting evidence.

However, it is interesting to note that the Slavery Hypothesis remains widely accepted today, despite the numerous criticisms that exist. It is still described as truth in medical textbooks and peer-reviewed literature, in the New York Times, the American Journal of Cardiology, Science News, and even by Oprah and Dr. Oz. As a result, ideas about genetic determinism and the biological basis of race have once again become a focus of scientific research. Acceptance of this hypothesis would presumably imply the acceptance of the idea that race is a biological, not social, construct. I agree with Moalem when he states, “From a medical perspective, it’s clear that specific diseases are more prevalent in specific population groups in a way that is significant and deserves continued, serious exploration” (65). However, this does become an issue when ideas such as that of eugenics arise. These ideas regarding the biological and social constructions of race are obviously a reoccurring theme in this class and remain an interesting topic of debate.

Survival of the SIckest

Survival of the Sickest offers an interesting perspective of evolution to the casual reader. The handful of Americans that do believe in evolution (joke) likely think in terms of ape-like creatures morphing into humans or survival of the fittest, some even considering the evolution of birds from dinosaurs or the mutation of viruses like HIV/AIDS. But Dr. Moalem leaves such readers with a very different appreciation for the wonders of this theory. He describes evolution as constantly dynamic, for better or for worse, and implicating all different organisms on the planet. I read the book quite avidly and quickly, especially given the accessible language and sensational examples. He starts off personal before getting into these examples, into his journey to investigate hemochromatosis, and subsequently the evolutionary reason behind numerous ailments. I especially enjoyed how he emphasized the genetic interaction of DNA of bacteria, viruses, and us as mammals. This portrays earth as a cohesive and dynamic enormous organism, all interconnected and evolving as a whole, subsequently taking the individualized notion of evolution out of people’s head, which I found very pleasing. If people adopted this former image into their political and everyday life, perhaps we would lead a far more satisfying and holistic reality.

I did maintain a few qualms about the book, mainly concerning the scientific evidence he uses to support his loose thesis. I wondered why he hadn’t used more concrete and solid research to support his claims, but rather became stuck on light ‘junky’ science. The last edition of the book was titled Survival of the Sickest: A Medical Maverick Discovers Why We Need Disease. Upon seeing this I was also left me wondering every time I read something especially surprising; what would non-mavericks in the field think of this? Why did he need a professional speechwriter to help him write this popular science book? There is a point at which Sharon states that some of his claims are still being investigated, or some words to that affect. Nevertheless, I believe he was more intent on offering an invigorating and different perspective on existence, and for me he succeeded to some degree.

Aquatic Ape Hypothesis and Water Births


In Survival of the Sickest, I found the discussion about the aquatic ape hypothesis to be extremely interesting.  The hypothesis is strongly supported by Elaine Morgan, a writer who became interested in evolution and in particular reproduction.  Traditionally, the idea is that humans evolved from a chimpanzee or ape that moved from the forest to the plains.  Because of the change in their environment, they had to learn to walk upright to obtain food, and over time evolve in humans.  However, Morgan presents another theory that is supported by research conducted by marine biologist Alister Hardy. The aquatic ape hypothesis states that our distant ancestors spent a majority of time near water.  The ability to spend time on land or in water gave them protection from land animals (cheetahs) or water animals (crocodiles).  As a result, these apes would evolve towards bipedalism since “standing upright allowed them to venture into deeper water and still breathe, and the water helped to support their upper bodies, making it easier for their bodies to support them on two feet” (199).  This lifestyle near water also helps to explain why humans lost their fur, and developed downward-facing nostrils.  I never heard of this hypothesis before and was shocked when I read about it.  For me, it seems pretty convincing, and I would love to learn more about this theory.
Moalem goes on to relate this theory to childbirths today.  He writes, “Childbirth in humans is riskier, is longer, and certainly seems more painful than it is in any of our genetic cousins” (194).  These complications are due to large skulls and narrow birth canals.  But if we take into consideration that we may have possibly evolved from an animal that had a similar structure to us who lived near water and who most likely gave birth in water, then maybe it would be beneficial to us today to give birth in water.  I would this connection to be very interesting.  After looking up more about waterbirths, I found that several celebrities have chosen this for their own labors, including Gisele Bundchen!

http://www.americanpregnancy.org/labornbirth/waterbirth.html

http://abcnews.go.com/Health/Wellness/gisele-bundchen-makes-water-births-sexy-delivering-son/story?id=9721599#.T0wAAWAlboA

http://celebritybabyscoop.com/2011/06/08/celebrity-home-births

The Evolution of Dairying

On page 88 of Germs, Guns and Steel, Jared Diamond mentions in passing the role that large, domesticated animals serve in nourishing early agricultural communities—they provide meat, aid in crop production, can be used as farm hands, and can be milked. These mammals, Diamond says, “yield several times more calories over their lifetime than if they were just slaughtered and consumed as meat.” For a family with a plot of land and many mouths to feed, this self-sustaining model is fantastic. Compared to other species in the animal kingdom, though, humans are quite odd. We’re the only mammals that consume milk after infancy, surprising because lactase, the enzyme needed to digest lactose, is highest just after birth and diminishes with age (hence lactose intolerance), suggesting that milk is perhaps only necessary and beneficial in the first few months of life.

When I think of milk and milk products, one thing I always bounce back to is who in their right mind decided to milk an ungulate’s udders?? It’s a little bit weird! I’m not that naïve, though—I realize that milking is only mimicking what babies of many species do to obtain nutrients and calories from their mothers. But why, after exhausting our human mother’s resources, do we find it necessary to switch to milk from other species and use it for milk, cheese, yogurt, ice cream and other dairy products? According to the ever-trusty Wikipedia, milking animals coincided with the development of agriculture, appearing independently in 9000-7000 BC in Southwest Asia and 3500-3000 BC in the Americas. There are many theories about how and why humans came to milk animals, a marked departure from the diet of a hunter-gatherer, who would probably consume virtually no dairy. While it remains unknown exactly when and how dairying came to be, it’s certainly a livelihood for many and a considerable part of the SAD (Standard American Diet) and diets in other parts of the world.

As an aside, from the general information that I know about lactose and lactase and human’s uniqueness in dairy consumption, I have to question doctors’ recommendations to drink more milk. The idea that the calcium in milk is necessary for strong bones and proper growth (which can be found in other foods) is one of the government’s party lines (see My Plate and past food pyramids). If dairy is a relatively new addition to the diet, though, is it really necessary?

Diuresis and the Cold

After reading Survival of the Sickest by Dr. Moalem, I have to say I agree with a lot of the research and data that he presents. I especially found the chapter about the cold weather to be true. I never realized how the systems worked to make the torso of your body warm, while the fingertips and toes are freezing. I do however, experience this often when it is extremely cold outside and especially when it is snowing. Even if I am wearing the heaviest gear, under armour, gloves, double socks, etc, my hands and feet will continue to be frozen as long as i stay outside, however the rest of my body barely gets cold, and if it does its only after a few hours. Although I know this is a form of defense for our organs, it sucks because if you want to have a snowball fight, or go skiing for the whole day it is bad. I am a frequent skiier so I know exactly how this feels. My ski boots do not even remotely keep my feet warm, and now I realize that its because al the blood is going to the center of my body to protect my vital organs.

Additionally, the bit Moalem wrote about having to pee whilst being cold was entirely too true. Whenever I'm on the ski mountain, I always get the urge to pee at random intervals. It always happens to be when I'm at the coldest part of the mountain too, right before I am about to go down the trail. Really??? I absolutely hate the feeling because it is so uncomfortable and such an annoying process to have to go to the bathroom while at a ski place. Internal pressure as a reason seems to make some sense because at the coldest part of the mountain, there is more pressure from the inside of your body, and the increased blood flow to certain pars in order to keep you warm. This seems like an extremely debated about question that I too would like to know the answer too. Why do we have an urge to pee whenever it gets really cold outside?? Any thoughts...

Monday, February 20, 2012

Intrigued, but Not Yet Convinced


So far, Survival of the Sickest has been an entertaining and fascinating read.  Personally I find this book to be more accessible than Why Zebras Don't Get Uclers, mainly because there are fewer references to medical jargon and long-winded explanations of bodily functions.  That being said, I also find the book to be far less convincing than Why Zebras Don’t Get Ulcers.  While Zebras was admittedly a bit tedious for me to read, I felt myself nodding my head in agreement to many of the points raised.  When reading Survival of the Sickest, the tone of the book and literary techniques used to prove ideas (such as the link between sunglasses and a decrease of melanin) reminded me of The Tipping Point or Freakonomics.  Books like the The Tipping Point are very mind-opening and encourage the reader to view seemingly common things in a unique perspective, but they have also come into debate for being too superficial in reasoning or lacking a wider medical perspective.  

Likewise, the arguments I have gleaned so far from Survival of the Sickest are undoubtedly interesting, but seem more like information that I would tell someone as a fun fact, and not necessarily something that I would be prepared to defend if prompted to.  For example, while I find the evolutionary and historical links of iron levels, diabetes and the Ice Age to be particularly compelling, I am not convinced.  With an unprecedented level of migration and interracial marriages occurring in the past thousands of years, it is difficult to concretely pinpoint the cause as being purely genetic or due to evolutionary reasons. Especially since we are learning abut the sociology of medicine, it seems important to also consider how other social factors, besides from race and gender, could have contributed to certain genes being perpetuated.  All things considered, I still find this book to be completely fascinating and I am looking forward to reading the rest of the book and see whether some of my concerns are addressed further on.   

E Pluribus Unum

Chapter VII in Survival of the Sickest really stood out to me in light of our extensive discussion of factors that may contribute to low-birth weight children. In particular, the fat mouse experiment at Duke which showed that a nutrient-dense diet during pregnancy can lead to a fat mouse giving birth to a skinny mouse. What else caught my attention was the fact that the first few days of conception may have important implications over the course of that child’s life. This struck me as just another factor that contributes to inequalities among society. We learned in lecture that the wealthy tend to plan their pregnancies more whereas the lower classes tend to have unplanned pregnancies. Assuming everybody takes equal precautions for better health during pregnancy, if lower classes don’t know they’re pregnant until further into it then they’re less likely to cut back on behaviors that may harm the fetus, such as smoking. This chapter also provided information about how being exposed to smoking can flip on or off certain genes, which could further harm the health of the fetus. This seems to imply that they have less of a chance to ensure that their children will have better health and the more the inequalities in society will continue. I was reminded of Why Zebras Don’t Get Ulcers when it’s mentioned that “The more unequal are incomes in a society, the more pronounced will be the disadvantages to its better-off members from public expenditure, and the more resources will those members have [available to them] to mount political opposition” (Sapolsky, 380). While this particular passage is emphasizing that the wealthy in unequal societies will derive more of a benefit from spending on private goods than on public goods which further divides the society, there is still the idea that the wealthy can better afford prenatal care and can better plan for the birth of their children. This being the case and assuming that the first few days can have tremendous implications in epigenetics, then the wealthy continue to benefit the most. But it should be addressed that inequality in society has costs on both sectors of society since the wealthy are essentially isolating themselves from the rest of the society while everybody else has to live with the consequences of living in it. This is certainly the case in America with increasing income inequality. Although lower classes are harmed the most, it hurts all of society to have this inequality continued. I’m reminded of Adam Smith’s saying that “No society can surely be flourishing and happy, of which the far greater part of the members are poor and miserable.” Not only does income inequality negatively effect lower classes because of worse access to medical resources, poorer quality of foods, but as we read in Why Zebras Don’t Get Ulcers, being on a lower rung in the social hierarchy has negative effects psychologically which can manifest into having a negative physical impact. It makes me wonder, what if the fat mouse was provided a nutrient dense diet but also had to suffer stress? Would it still give birth to a skinny mouse? If so, that provides a glimmer of hope for preventing health complications and reducing inequalities.

On a completely different note, the Atlantic recently published an article that elaborates on T.gondii, the parasite carried by cats discussed in Chapter V of Survival of the Sickest http://www.theatlantic.com/magazine/archive/2012/03/how-your-cat-is-making-you-crazy/8873/ It’s weird to think that something as innocuous as a housecat may actually be impacting our mental health.

Thoughts on the Geritol Solution?

In Survival of the Sickest, Dr. Sharon Moalem explores the evolutionary perseverance of widespread modern diseases (diabetes, high cholesterol, etc.) She aims to explain why such a trait has been evolutionarily conserved despite its possibly fatal effects. To do this, she answers her own question:

“Why would you take a drug that is guaranteed to kill you in forty years? One reason, right? It’s the only thing that will stop you from dying tomorrow. (14)”

In many ways, this quote is the essence of the first give chapters of her book. It serves its primary purpose as a jumping point to thinking about disease over the course of evolution. Because of its ability to instantly evoke a more detailed thought process, I also see it as a preview of her exploration of the interconnected nature of evolution and the environment.
Moalem begins with the example of the disorder hemochromatosis, which is characterized by the chronic buildup of iron in the bloodstream. She explains how this could have been evolutionarily favorable at one point in history (specifically, during the Bubonic plague) because of iron’s ability to enhance the immune system through the “iron-locking” response. She goes into great detail of the biochemical nuances of iron, giving multiple examples of how it can be both essential and fatal.
It is mentioned that iron is necessary for microbial life. She briefly mentions the Geritol Solution, which is the idea that dumpling iron into the ocean will stimulate microbial oxygen production and can therefore counter rising atmospheric CO2 levels. Moalem does not take a position on this idea and does not elaborate on it much, but it stuck in my mind as being a particularly shortsighted concept.
One of the main ideas that I took away from the first half of Survival of the Sickest was concerning how changes in the environment could have had long lasting effects on evolution and the genetic makeup of society. From the previous readings we’ve done in class, we’re all well aware of the ability of the environment to allow a genetic disposition to manifest as disease. I feel that this way of thinking about the effect of environmental factors is in disagreement with the principles behind the Geritol Solution. Dumping artificially huge amounts of iron in the ocean could have disastrous side effects on the environment, and the therefore altered environment could then have long lasting consequences on health and society.
I can understand that Moalem’s reference to the Geritol Solution was purely to illustrate the effects of iron, but the concept just struck me as being especially odd.

Feeding Ourselves and Bacteria

We all know that consuming uncooked poultry may lead to a bout of salmonella and even bagged spinach and sprouts--not just contaminated meats--can spread e.coli through runoff water contaminated with fecal matter. Food can make us sick by introducing additional bacteria to our bodies and overloading our immune systems to a certain tipping point making us extremely ill. What's gaining more and more publicity lately, however, is what the U.S food industry does to preemptively combat the bacteria we are vulnerable to consuming: loading the livestock we eat with massive quantities of antibiotics.

In "Survival of the Sickest" Dr. Sharon Moalem exposes that some diseases are actually very sophisticated, adapted responses to former environmental threats to human health. He focuses especially and continuously returns to his very personal discussion of hemochromatosis--a disorder which traps and locks excess iron in the body (albeit unevenly). I had always been under the assumption that iron is almost always a good thing for the body and as a vegetarian, I find myself on a perpetual quest to add more of it to my diet. Moalem, however, proved me very, very wrong as he discussed how those with hemochromatosis (which neglects to spread iron to certain microphages in the body) and anemia are actually far less susceptible to certain diseases and bacteria which feed on iron as fuel. Iron is constantly added as a supplement in many of the pulses, grains, cereals, and multiple other foods we eat and also an additive in baby formula.

So, why talk about antibiotics when Moalem discusses iron?

The issue is that both iron and antibiotics are added in excess to what we eat daily. As we consume more and more antibiotic-laden meats (and milk), our bodies become resistant to the antibiotics that are helpful (in moderation) to cure us when we fall ill. Strains of antibiotic-resistant, dangerous bacteria such as MRSA is becoming far more commonly diagnosed in the US and this seems to be no coincidence. What about iron? Am I suggesting you turn down that plate of spinach for a slice of pie? No. But as Moalem puts it, too much of a good thing is not always a good thing. It seems to me we are adding too much of a good thing to our bodies and, in the process, making everyone more susceptible to the bad stuff.

Eradication of the Guinea Worm Disease

As I read the first few chapters of Survival of the Sickest, its' focus on the Guinea worm disease was interesting to me. It states, "...Guinea worm infections had dropped from 3.5 million in 1986 to just 10,0674 in 2005. By understanding how the Guinea worm has evolved in relationship to us..." (96-96). When I first read this statement, I thought it was a very good happening. However, I realized it has taken twenty years for these results to occur and President Jimmy Carter expected the disease to be eradicated in 10 years, according to the article "Final struggle to eradicate guinea worm disease" written in 2007 (http://www.msnbc.msn.com/id/17650015/ns/health-infectious_diseases/t/final-struggle-eradicate-guinea-worm-disease/#.T0LUeoemhvk). Also, about 1,000 new cases in Ghana arose in that year, making eradication difficult. I was curious about the update on the disease so I found another article stating that in the year 2011, there are only 1,060 cases (http://www.examiner.com/infectious-disease-in-national/eradication-of-guinea-worm-disease-is-closer-than-ever). And recent news say that foundations that are part of the eradication process hope to eliminate the disease by 2020.

Reading all of this brings me back to Ewald's theory (pg. 120-123). I believe that the Guinea worm disease may have not been eradicated earlier because "bacterial evolution gives bacteria an advantage over us". Although it may seem that the eradication process may come to a final end soon, I won't be surprised if it won't happen by the year 2020. I wonder if more practical ways can help further the process such as educating the children since they are the majority of victims.


Guns, Germs, and Steel

*Newsflash....I read the first half the wrong book. Fantastic.*

From what I've read (up until chapter 10), I thought Guns, Germs, and Steel was interesting in some ways, but overall kind of dry. I admire the author's intense detail of possible cases and examples supporting the usually all-inclusive hypothesis he sets up (such as the conquering of Latin America by the Spaniards), but personally I was more interested in the way he set up many of his arguments with questions that supposedly have been answered by (usually) white philosophers/researchers/scientists.

One such discussion was about human intellect and how some try to say that white/European people are genetically disposed to being smarter. Diamond goes on to refute this fact by putting this into perspective. Due to the advance of medicine and technology, more and more arguably "less fit" people are passing on their genes to subsequent generations. However, in these isolated societies such as the Guineans, tougher living conditions and the unforgiving nature of disease and disaster have only allowed the "fittest" to survive. I thought that was very interesting, because I, usually think of intelligence in the Western sense, in terms of a knowledge bank. Diamond points out that the people he encountered in New Guinea were among the most intellegent people he's met, but not in a book or subject sense. Additionally he noted that they could take up industrialized methods and techniques very quickly if taught.

On the whole, I was also interested in his emphasis on luck and geography. He points out that geography directly affects wildlife diversity and potential problems for species living in certain areas, among countless other factors. These factors can then be used to how some human societies were able to take advantage of their situation and prosper. I had always learned the history of such sequences was more related to the psyche of the people - the smart and strong conquered, but Diamond's intricate explanations showed me that chance and environment were much more important in the development of history than most think. I thought this ties into our discussions regarding health outcomes in society being a direct effect of one's environment, starting with pre-natal conditions. By reading this, I am leaning much more toward the idea that health is far more effected by environment than genetics, barring genetic disease. I look forward to maybe reading about more of the health effects in history in the second half of the book.

Evolutionary Basis of Albinism


I found the first half of Dr. Sharon Moalem’s Survival of the Sickest to be fascinating. His idea that today’s detrimental and sometimes deadly health conditions, diseases, and illnesses exist because they were once beneficial and advantageous to survival is quite fascinating,

I found Dr.Moalem’s discussion of sun exposure, cholesterol, Vitamin D, and skin color to be particularly interesting. He writes that, “the wide range of human skin color is related to the amount of sun a population has been exposed to over a long period” (p.53). He further writes that, “The milk white skin of an albino is caused by an enzyme deficiency that results in the production of little or no melanin.” (p. 53) The latter line was personally significant to me as I have albinism.

Albinism is an autosomal recessive genetic condition that causes a lack of pigmentation in the hair, skin, and eyes. This results in pale hair and skin and a significant visual impairment (typically legal blindness, nystagmus, strabismus, astigmatism, photophobia, near sightedness, etc.). Because individuals with albinism do not tan and only burn upon exposure to the sun, we tend to avoid the sun (stay indoors) or slather on sunscreen even on overcast days. This results in limited UVB exposure, and our cholesterol does not get converted to Vitamin D efficiently. As a result, many of us have a Vitamin D deficiency or insufficiency.

I was disappointed that Dr. Moalem did not indirectly hypothesize or directly address how/why albinism and/or the enzyme deficiency which causes albinism may exist now due to having been particularly advantageous to survival at some point and time in the past (other than saying that human skin color is related to long-term sun exposure… I suppose this means that albinism evolved in individuals who lived in an area with no sun exposure and thus did not need any melanin…?). Currently, as global warming progresses, having albinism does not seem particularly advantageous.

I decided to do some research into this topic. While I was unable to find any credible information about the advantageous evolution of albinism in humans, it seems that albinism evolved independently in two different species of Mexican cavefish as a result of their habitats. Since these species live in perpetual darkness, over time, they have lost their pigment, and their visual acuity has also decreased. http://www.sciencedaily.com/releases/2005/12/051220000639.htm

I am curious to know whether being a carrier of the gene for albinism or having the condition itself is or was ever advantageous in some respect in humans or other species.

Sunday, February 19, 2012

Stress Affecting Growth

I have a lot to say personally about Chapter 6, about the importance of stress on growth factors. I completely agree with all the research that has been found on this topic. When children are young,they need the optimal care they can get and not just material objects, they need love, comfort, care, touching, interaction, something to grasp onto. I have learned about the Harry Harlow monkey experiments in countless psychology classes. The theme of his research seems to be over arching in childhood development. It is related to that of a rat or a monkey because when put under stressful situations like only having a wire mother who feels tough and cold to hang onto and feed from makes the monkeys scared and not want to be placed in social situation so this inhibits their development. I feel that every stressor that life presents you can make the growth system in the body slow down. This holds true later in life as well, especially around the times of puberty. For example, young girls who have societal pressures to be thin at such a young age due to what they are seeing in the media, the perfect image. They try to replicate this image by becoming bulimic or anorexic at a really young age, like in their pre teens and then they are late to get their periods or don't get them for a couple years. This can cause detrimental effects on growth because girls need that estrogen to grow and develop. 
 
Additionally, a divorce between the parents of a family can cause great stress on the children whether they are at a young age or in their teenage years. It is like a bond is being broken in the family and everything is splitting up. The world they once knew is totally and completely different, never to be reversed again. Dealing with this kind of pain takes a long time and even if the children might not outwardly show it, there are signs of their emotional detriments in their everyday activities at school and with their friends. They will always seem down or they might put on a completely different image or mask to make it seem like it has not been affecting them. Even if they find an outlet of release for their pain, the stress will always follow with them because family is such a huge part of a child's life. When this kind of event happens during puberty it can have altering affects on the child's growth patterns and everything.  There are a million and one things that can cause stress to a child during the development period its just a matter of when the stressful event occurs and how it is dealt with. 

Monday, February 13, 2012

Stress

"A large body of evidence suggests that stress-related disease emerges, predominately, out of the fact that we so often activate a physiological system that has evolved for responding to acute physical emergencies, but we turn it on for months on end, worrying about mortgages,relationships, and promotions."(p.6) In the book Why Zebras Don't Get Ulcers, Robert M. Sapolsky makes a great comparison between animals and humans and how stress affects our bodies. Looking from a zebras perspective, the things which stress us out on a daily basis are ridiculous. Meanwhile they stress out over survival, we don't think of major disasters or death on a daily basis so we look into smaller irrelevant things to worry about. For example mortgages, relationships and promotions, not even one of those relates to our health or our survival chance yet they are among the top things which we stress over about. I have read once that the more you stress out about certain situation or even the less likely it is going to happen, and from experience I believe it to be true. For example asking a person on a date and stressing out all the different possibilities of them rejecting you or something going wrong, but in the end everything works out great, or messing up at work and stressing about getting fired meanwhile your boss might not even notice, or doesn't see it as a horrible situation.

Students and Stress


As college students, we tend to feel pretty stressed on a regular basis.  With getting that paper done on time, going to work, internships, relationships (or lack of any of these things), our lives are hectic and stressed.  Add to this situation the fact that we are going to school in New York City, a place where people are always on the move, rushing around and stressed.  Sapolsky even states that exposure to New York City is a risk factor for a fatal heart attack due to the high levels of “stress, excitement, fear, and disruption of sleep/wake cycles than in most other places” (49).  Reading this book is even making me stressed, thinking about all the ways that I am slowly shortening my life.  At the same time, I learning ways to improve it, so it evens out.  What I found particularly interesting was the section on stress and eating.  I was comforted by the fact that I am with the majority and tend to eat more while stressed.  I now realize this is due to the levels of glucocorticoids which cause the cravings for the delicious starchy, sugary foods.   However as Sapolsky concludes, our responses to stress vary by individual.  This is true for the effects it may have on appetite, but also other factors such as risk for heart attack and strokes.  Even though stress varies from each individual, we can agree that it is not good, and can have long term consequences.  As a result, I think it is important to try to eliminate certain situations that may cause us stress.  While we cannot simply get away with doing that final research paper claiming it is bad for us and will cause us to have a heart attack one day, we can take steps to dealing with the stress.  Sapolsky discusses these methods, such as exercise and meditation, in his final chapter.  Overall, I find this book very interesting and look forward to sharing this information with family and friends. 

The Inheritance of Child Abuse

This morning I happened across an an interesting article in the Bloomberg News that seemed quite relevant to class. A Harvard University study suggests that childhood abuse can lead to physiological disruptions in the hippocampus, which causes adult depression and drug abuse down the road. Young men who had histories of child abuse demonstrated differences in parts of the brain where new neurons are generated, and have less dense (up to 6.5%) hippocampus tissue, which processes emotions, fear, memory etc. Dampening activity in this part of the brain has been linked to depression and schizophrenia. In addition people who have endured this type abuse are more biologically sensitive to stress, and such factors may shorten their life expectancy by as much as 20 years, other studies indicate. On a more cheery note, it is also noted that certain drugs and lifestyle changes can prompt the formation of new neurons!

http://www.sfgate.com/cgi-bin/article.cgi?f=/g/a/2012/02/13/bloomberg_articlesLZCANO1A74E901-LZCJQ.DTL

I think this was interesting in context of our conversation of genetics vs inheritance. One would assume that changes in the composition of our brain and psychiatric condition is overwhelmingly genetic. The physiological manifestation of a social phenomena (such as child abuse) is a fascinating contradiction to this genetic excuse, and instead indicates that many 'inheritable' traits, such depression may have roots in behavior. Perhaps parents who mentally and physically abuse their children have higher chances of being substance abusers or depressed, resultant from a long chain of child abuse in their family. The inheritance of child abuse! This parallels our discussion of social conditions vs genetics in the inheritance of low birth weight risk. The article briefly delves into the financial burden of child abuse on society and healthcare, which I also found interesting.

Reduction of Anixety Through Meditation

Anxiety is a psychiatric disorder that Sapolsky describes as being “rooted in cognitive distortion” (319). An anxiety-prone person’s thoughts create a psychological state of dread and apprehension, which in turn affects how they feel and act. As a result of the excessive worry, people diagnosed with anxiety disorders have abnormal, chronically overactive stress responses, which leads to an increased risk of many diseases. A widely used method of dealing with anxiety disorders is through the use of cognitive behavioral therapy. Cognitive behavioral therapy is an approach that attempts to systematically recognize and eliminate dysfunctional thoughts, which will change how we feel and our behaviors. While this method has been proven to be effective, there has been a rise in the usage of alternative treatments, a major one being mindfulness mediation.

Sapolsky mentions the use of meditation as a technique for managing stress. Meditation is used to increase our ability to relax, which in turn should increase our ability to cope with stress more effectively. While there are many different forms of meditation, the form that the majority of the scientific studies have focused on is mindfulness meditation. The goal of mindfulness meditation is to make create stability and peace in our minds while increasing awareness. Researchers have been studying the effectiveness mindfulness mediation based treatments in reducing anxiety. Through randomized trials, it has been shown that mindfulness meditation therapy can significantly reduce anxiety, as well as successfully improve mood, functionality, and quality of life.

A study published in Psychiatry Research: Neuroimaging, used images from the brain throughout an eight week long mindfulness mediation based stress reduction group to show that actual structural changes occur to our brain when we meditate. Reductions in stress were found to be associated with decreased grey-matter density in the amygdala, which, as Sapolsky explained, plays a very important role in anxiety disorders. These studies show that mindfulness meditation should be increasingly used as a therapeutic technique to reduce anxiety. Meditation could possibly be used as a prevention method before a person is inflicted with a stress related disorder. It would be interesting to possibly study other forms of meditation in order to see if their effectiveness in anxiety reduction differs. Another interesting possible study would be to track the long term effects of meditation and health outcomes in order to discover if any other ailments can be treated or prevented with such a method.

http://www.sciencedaily.com/releases/2011/01/110121144007.htm

http://www.columbia.edu/itc/hs/medical/cp4/client_edit/topic4/sg3b-1.pdf

Sunday, February 12, 2012

Marathons and Health

In a study spearheaded by Dr. Stanley Nattel of the Montreal Heart Institute Research Center, “Canadian and Spanish scientists prodded young, healthy rats to run at an intense pace, day after day, for three months, which is the equivalent of about 10 years in human terms. The training was deliberately designed to mimic many years of serious marathon training in people.” By the end of the study, these formerly healthy rats exhibited scarring and structural changes in their hearts and were more prone to irregular heartbeats, not unlike in humans. “Interestingly, when the animals stopped running, their hearts returned to normal within eight weeks. Most of the fibrosis and other apparent damage disappeared.”

This study, designed to assess the toll that sustained, intense training takes on a person’s physiology, highlighted exactly what some may find the definition of insane. As Sapolsky on page 123, “sit with a group of hunter-gatherers from the African grasslands and explain to them that in our world we have so much food and so much free time that some of us run 26 miles in a day, simply for the sheer pleasure of it. They are likely to say, “Are you crazy? That’s stressful.”” He also addresses the negative correlation between long distance running and fertility (because of low testosterone and estrogen production) and bone health.

I found this topic worth looking into because, in general, we try to get people to exercise more (if at all) to reap its many physical and psychological benefits, but once in awhile a story breaks of a death during a marathon or debilitating injury from improper training and it’s interesting to see there are some people who find pounding the pavement for 26.2 (or longer!) an enjoyable pastime. More may not always be better, but for whomever wants to wake up early for long training runs dedicate their free time...more power to them!

http://well.blogs.nytimes.com/2011/03/09/when-exercise-is-too-much-of-a-good-thing/?scp=5&sq=marathons%20and%20health&st=cse#

Tuesday, February 7, 2012

Deeper Issues of Low Birth Weight


One of the more thought-provoking points raised by The Starting Gate is the link between low birth weight and race.  When examining the high occurrence of African-Americans giving birth to lower weight babies than other races, one may be led to believe that there is a genetic causation involved.  Conley et al, however, suggest that the societal factors associated with some African-Americans, such as lower income and socioeconomic status, are more to blame than genes.  Furthering this point, when social scientists examined the birth weights of infants born in West Africa, they charted a more normal trend of birth weights than African-American babies.  

With this staggering information, along with the harrowing details of potential health risks for low weight babies, the question of how we can fix this inevitably arises.  While Conley points out policy reforms, such as Medicaid, which can help treat and aid babies with low birth weight, perhaps a more significant reform is mandated in order to mend the issue at its root.  The deeper issue is that there is an inequality and wealth gap that is so substantial that it actually impacts a person’s biology.  Not only is the affected person living in poverty with low social status, but a monumental problem is also that his or her child will almost certainly be stuck in the same predicament and highly unlikely to advance.  If the child is born with health issues, accompanied with the risk for illness later, then a large portion of the family’s income will be allocated towards medical funds. With the perpetual shortage of money, it becomes almost impossible to transcend to a higher class.  Thus, the cycle of low birth rate will probably perpetuate amongst a lineage. How to fix inequality in society has always been a heavily debated topic with no definitive answer.  While it is easier said than done, more focus nevertheless should be placed on conceptualizing how to minimize the inequality gap, and thereby minimizing the trend of low birth weights.