Sun: hero or villain?

The most interesting chapter from Survival of the Sickest, at least from my perspective, was Chapter III "The Cholesterol Also Rises" because it addressed the grim reality, that what we cling onto for our survival is also contributing to our demise. Prime example, the sun. Without the sun nothing around us would be possible because we have it to thank for our food and air supply. On the flip side, the sun can also cause drought, which often limits the food supply, and deadly skin cancer. I appreciated this combative chapter so much, because there is constantly debate over what promotes health, what chips away at it, what lengthens life and what shortens it. What one person thinks is okay, another person says it should be avoided. I think that judging from our past reads, the stress caused by such worry might be more damaging than the product itself. Now, I am not talking about something like smoking, which I can find no benefit to, but if someone enjoys drinking a diet soda in moderation, then they should do it without worrying about something like cancer that seems to be caused by everything these days. Sticking with the same example, if soda is labeled as a taboo thing in someone's diet, then more likely or not it will become something obsessive and tempting, when it really is something trivial. I think that living by the rule of moderation will keep people happier and more prepared for a long, healthy life.

Moalem's Evolutionary Tales

I have found Dr. Sharon Moalem's Survival of the Sickest to be the most enjoyable reading that we have assigned.  Perhaps, this is because he presents his argument through a series of interesting stories.  From learning about the relationship between skin pigmentation, UVB absorption, folic acid depletion, and Vitamin D production, to discovering the phenomenon behind Asian's "flush" response to alcohol -- Moalem expresses the idea that evolutionary processes, based on geographic and population changes over time, account for many patterns of health that exist in present day. Disease is typically cast in a negative shadow, that Survival of the Sickest, works to readjust by conveying the potential benefits (some essential for survival) that many illnesses had for our ancestors.

The portion of Moalem's book that I believe to be most interesting is the second chapter, "A Spoonful of Sugar Helps the Temperature Go Down."  Specifically, I enjoyed his discussion on the wood frog, Rana sylvatica, the connoisseurs of cryopreservation. At first, it may not seem like a huge deal that these wood frogs are able to sustain an unconscious, frozen state throughout the winter and revamp their metabolism come spring.  How might this adaptation, however, be an invaluable tool for human beings?  First, the ability to revitalize living organisms that have been preserved at very low temperatures, has enabled scientists and doctors to store banks of eggs and sperm that, when unfrozen, maintain the full capacity to be fertilized and develop into viable embryos.  Taking this concept to the next step is what I find particularly exciting - can this sort of technology allow us to preserve entire organs that can be stored and used for transplants? At current, unfortunately, no.  However, I think that this sort of technology will one day be sophisticated enough to allow for long term preservation of human organs. Moaelem describes the various features of the wood frog and suggests the possibility that these characteristics be used to develop strategies for human organ preservation.  For example, the wood frogs essentially diminish their water supply and shoot up their glucose levels in preparation for their deathlike winter.  To carry this idea further, I think it would be interesting to sequence the genome of this frog, with the hopes that the genetic makeup for this adaptation may somehow be able to be utilized in order to manipulate the ability of human organ to hibernate.  The development of such technology would change the face of medicine forever, as it would increase survival rates for patients suffering from  terminal illnesses, such a cancer or heart disease, who require organ replacement in order to live.

Dr. Moalem's Theory applied to Bacteria Infecting Viruses

When reading the last half of Dr. Sharon Moalem’s book Survival of the Sickest, I was reminded of a recent lecture I had in my Gene, Structure & Function class. In class, we talked about a special type of virus that infects E. coli bacteria. This virus is called lambda phage. This virus has been studied a great deal because it contains clues to understanding the molecular processes of other viruses and additionally it is relatively easy to work with in a laboratory because of its small size. Furthermore, this virus is an important research tool because it has two separate life cycles that it may choose between. One life cycle, called the lytic lifecycle, results in the immediate death of the host cell. In the other life cycle, called the lysogenic lifecycle, the virus integrates into the bacteria’s DNA and lays there dormant for an indefinite amount of time. The factors that cause lambda phage to choose one lifecycle over the other are not yet fully understand, but they hold great implications for discovering what makes other viruses, like say HIV, switch from being dormant to being deadly.

In order to integrate into a bacteria cell’s DNA, lambda phage must bind to a specific site on the host cell’s DNA. In one study, researchers removed this binding site on host cell’s DNA to see what would happen. Within a very short period of time, the cell evolved another binding site, allowing the virus to integrate into its DNA. Why on earth would a cell evolve to help a parasitic virus infect it? My teacher came to the conclusion that the virus must somehow be beneficial to the bacteria cell, although it also has the potential to kill the cell at any moment. This sounds an awful lot to me like the argument that Dr. Moalem was making in Survival of the Sickest. All of this is just my long way of saying that I think that Dr. Moalem’s theory that certain diseases may be beneficial to certain organisms holds water in molecular cell biology as well as evolutionary human biology. 

Epigenetics

or...shut up already about nature versus nurture. The nature versus nurture debate has always bothered me because the two interact with each other and reducing humanity to one or the other seems pointless.

I found the following quote to be amusing: “DNA is destiny—until you get out the old methyl Magic Marker and start rewriting it” (162). It shows one of the ways that viewing DNA as destiny, even from a more biological/nature perspective misses the point.

I find it an interesting topic to include, however, it should have been introduced with (instead of waiting until the chapter was more than halfway over) his disclaimer: “Right now epigenetics is in a bit of a the-more-we-know-the-less-we-understand phase” (173).

Although this whole topic of epigenetics is in many ways really useful and interesting, it is problematic to bring in studies where the outcome is so unexplained. The case of smoking grandmothers and asthmatic grandchildren is what I was specifically thinking of. In this study, “children whose grandmothers smoked while pregnant were more likely to have asthma than children whose mothers smoked while pregnant” (166). This is supposedly because epigenetic responses were triggered in the already formed eggs of the grandchild which were within the ovaries of the fetus. Moalem then adds, “Incidentally, if you’re puzzled as to why the grandmother’s smoking habits affected their eggs more than their fetuses, you’re not alone; scientists haven’t figured that out yet.” (166). When considering this as an example, I find this scientific bafflement to be somewhat disappointing. In order to fully understand this example and how it relates to his theory, this is the key point! Understanding why epigenetic responses occur in the eggs of the fetus but not in the fetus is entirely baffling and makes this a not so useful example to bring.

I was curious whether NYU has any epigenetics research, so I looked it up and apparently we do it on ants here. http://www.med.nyu.edu/biochem/ReinbergLab/HTML/antsMain.html

So the next example I found particularly interesting was the Michael Meaney study. Moalem explains that, “Meaney’s study showed that the interaction between mothers and their offspring after birth provoked the placement of methyl markers that caused significant epigenetic changes” (168). The study showed that, “Pups that were gently licked by their mothers grew into confident rat babies that were relatively relaxed and could handle stressful situations. But rats that were ignored by their mothers grew to be nervous wrecks” (168). Moalem explains this through the lens of the methyl markers and states:

“The mothers’ gentle attention somehow triggered the removal of methyl markers that would otherwise have blocked or impeded the development of a part of their babies’ brains—almost as if they were licking them off. The part of the brain that dampened the stress response was more developed in those babies. This wasn't nature versus nurture’ this was nature and nurture.” (169)

This is an interesting case to look at. It shows how nature and the environment influence biology. To me, this doesn't seem like such a big shock. I view nature and nurture as in a complex relationship, not as two separate entities. However, apparently this idea is in fact shocking enough that, “One reviewer at a prominent journal actually went so far as to write that, despite the researchers’ carefully marshaled evidence, he refused to believe it could be true” (169). Does anyone want to comment on why the researcher found this evidence to be so incredibly problematic as to not even believe it?

****UPDATED*****

I just found this really interesting study which claims that women can produce NEW eggs during her lifetime. This is a really interesting idea in light of some of the above cases as well as medicine in general! I didn't get a chance to look into it too extensively, but it certainly has vast implications for many of the theories we have been discussing in class. Take a look!

Survive and Reproduce

It amazed me to realize how many other little microscopic organisms coexist in our bodies. While I was aware of their existence, mostly every time I got sick, it never hit me until reading Survival of the Sickest. Sharon Moalem reveals, “not only do these former bacteria live in almost all your cells, they even have their own inheritable DNA” (129). This reminded me how in the introduction he mentions that even laying on our bed there are thousands of living organisms around and inside of you. It scared me to realize that some of these microbes can alter one’s nervous system, through host manipulation, in order to survive and reproduce. It is not like as if they are hijacking our nervous system and completely changing it but rather they manipulate it for their own survival. These microbes can be harmless in some but may be harmful for others. Moalem states that some scientist hypothesizes that T. gondii may trigger schizophrenia in people. It that is confirmed then we will be able to find a way to treat those with schizophrenia. Nevertheless, I still find it shocking that little microbes can affects us not only physically but also mentally.

Each organism’s goal is for survival of their gene’s and reproduction. Moalem mentions that if we figure out the ways parasites spread and we find ways to impede this spreading, like cleaning up the water systems or putting up mosquito nets, they will become less deadly to the host because it is harder for them to spread and infect others. What confuses me is how do they know that their means of reaching other hosts is thwarted and how can they tell that they need to stay in this host longer in order to survive? Moalem mentions that they do not have brains, and I do not believe that they can see things in a grand scale, so how is it that using these preventative methods stopping them? I suppose they can realize that they are not spreading pathogens to other host but without a brain how is that possible?

Mental Illness: Also Advantageous?

Survival of the Sickest? is definitely my favorite so far of what we have read so far for this class, because of the new way of thinking about health that it presents, and also because of the specificity that it draws on to prove it's point.  Thinking about disease as having a correlation to longevity is something that I would never considered, and probably even laughed at, were it not presented to me in the way that it was in this book.  Further, the book feels, to me, to be on the cutting edge of some of the most groundbreaking discoveries in the medical field.  Particularly interesting to me was the idea presented on page 156 of a pseudo-Lamarckian idea of the vices of a pregnant woman affecting her offspring, like an on and off switch that makes a gene express itself that otherwise might not have.  While I have always understood Lamarck's principles to be generally accepted as false, I find the prospect of aspects of this idea to be appealing, since it could help us to better equip future generations for life.

Considering the way of thinking presented in this text, I couldn't help but expand Moalem's idea to include mental illness as also having it's silver linings.  I know that I am getting away from the principle thesis that disease may increase longevity, but I would like to discuss how mental illness may actually increase chances of success for individuals in a more general way.  My first example of this idea is John Nash, the mathematician responsible for the now widely used game theory.  There are many books and films about Nash, including the Oscar gobbler A Beautiful Mind, but one which I feel is much more relevant to my discussion is a documentary by PBS: A Brilliant Madness.  The focus of these films is that, in addition to his breakthroughs in mathematics, Nash also suffered from (spoiler alert) advanced paranoid schizophrenia.  In the documentary, Nash states that he felt great pressure from this disorder, as he often felt that he was some divine messenger because of his ideas.  He states in these interviews that, as a result of this part of his condition, "I wouldn't have had good scientific ideas if I thought normally" and "If I had felt completely pressureless I don't think I would have gone in this pattern."  Part of this interview is transcribed here.  Nash's schizophrenia, while distancing himself from his family and effecting his everyday life, certainly played a huge part in his success in life.

Other examples include Jimi Hendrix, whose battles with manic depression influenced much of his work.  Another example includes football great Herschel Walker, who, it was found when his career had finished, had a severe and rare form of mental illness now known as dissociative personality disorder (previously multiple personality disorder).  In this video, Walker explains that his different identities would take on different roles, a father, a husband, a football player, a business man.  He recognizes this as a blessing to his wild success in athletics, but also a curse as he does not know who he really is.  If you are more interested in this, there is an incredible special that ESPN did called "Herschel" where he describes in detail what his different "alters" were like.

I realize that this may be a touchy issue, but I just don't think I would have thought about any of this if it hadn't been for this book.

Survival of the Sickest

Dr. Sharon Moalem's Survival of the Sickest is her attempt to challenge our modern understanding of illness. Survival of the Sickest begins by asking the reader to consider the concept that evolution is not simply one particular species adapting to its environment, but really a dynamic equilibrium where every organism within the system affects each other. This is a very apt metaphor that Dr. Moalem uses to frame the rest of the book, where she seeks to delineate the connections between evolution, disease, and health in the modern world.

For my blog post, I'd like to specifically examine how Dr. Moalem breaks down the importance of iron in the human body. The traditional understanding of iron is that it is one of the most important compounds used by the human body. It is required for "nearly every function of our metabolism", including the transportation of oxygen in our bloodstream and the conversion of sugar into energy. For many years, doctors and nutritionists "operated under the assumption that more iron can only be better", but more recent research shows that this is far from the truth. In fact, many of the parasites, cancer cells, and bacteria that assail our bodies thrive on iron, and adding too much iron to our bodies is simply providing more food for these assailants.

This key revelation is one of the central themes to Dr. Moalem's book. She wants us to consider disease from the standpoint of evolution - how is it that these certain genes have persisted in our DNA through all these years? For many years, we operated under the assumption that more iron could only be better for our bodies, but we failed to realize that if our own bodies require iron, then certain bacteria, fungi, and viruses would be extremely iron-hungry as well. I believe that the most valuable message that Dr. Moalem is trying to put forth is similar to what Robert Sapolsky was arguing in his book about stress, in order to understand disease and illness, we must utilize a perspective that incorporates all of the various factors, including other organisms and evolution.

Benefits of Disease?

While reading the second half of “Survival of the Sickest,” I stumbled across a passage in the book that reminded me of the first book we read, “The Starting Gate: Birth Weight and Life Chances.” On page 159, there is a reference to a study done at Duke about how, “nutritional supplementation to the mother can permanently alter gene expression in her offspring without altering the genes themselves.” This discovery heavily impacts the debate we had earlier about if low birth weight has to do more with genetics or the state of health of the mother during pregnancy (favoring the health of the mother during pregnancy).

I found it interesting that certain diseases that ail us today helped with the survival of our ancestors. I already knew before that even though bacteria, usually seen as nuisances that cause disease, are necessary for us to process certain foods and provide us with vitamins that we cannot get ourselves. However, I was unaware there were actually diseases such as diabetes that improved the chances of survival in the past but are now a cause of death in the present. His theories seem to be plausible but I find it hard to believe that they tell the whole story. For example, when he talks about men being more susceptible to catch the bubonic plague than women can be accounted for in ways beyond just the iron deficiency in women. Since the bubonic plague was a contagious disease, men could have been more likely to catch it because they spend more time out of the house around others since they were the ones that worked. Women during those days spent more time at home, away from the public giving them less of a chance to be exposed to those with the disease outside their family members. Besides that example, his other arguments seem very plausible and quite fascinating. After reading this book, I now wonder if there is something comprising our bodies today that will be seen as a disease in the future.

Evolution and Diseases

In Survival of The Sickest, Dr. Sharon Moalem, draws conclusions to the evolution of human and the diseases it brought together with it. Sharon Moalem believes that certain diseases travelled through genes and made it to existence today because they helped people survive natural selection. Natural selection is when the fittest species manages to survive in the conditions of the environment. That said, I am also convinced that culture and genetics have a role in which diseases certain groups of people are susceptible to.

The fact that people who had diabetes during the ice age had better chances in surviving does not mean that people today should have diabetes. Medicine should not be interrupted because of the evolutionary process that never stops. We are in a constant change, physically, mentally and cognitively, natural selection never stops, the one who cannot adapt to its environment is eliminated, and diseases keep on changing the social equilibrium. Along with Moalem’s theory, I think that some of diseases are just caught by the chance of mutations and cross overs in our genes, which leads to evolutionary differences. For example, some people are immune to AIDS and this is mostly caused by the mutations in their genes, they do not have the receptor in their cells that activates the AIDS virus; therefore they have zero chance of being AIDS. Maybe one day the human race can be immune to AIDS and this can be another example of how we survived such an age.

Some of the diseases are and will help us survive today, ones that we might not even be aware about at the moment. I think this book helps us think about evolution and medicine together in a way I never thought we could. 

Iron / Living Things

    Survival of the Sickest was an interesting read. It was made clear from the introduction where the author's message was heading: it spoke of how Dr. Sharon Moalem witnessed the long sickness and struggle of his grandfather, who eventually succumbed to Alzheimer's disease. As a fifteen year old, he intuited a connection between his grandfather's blood disease, hemochromatosis, and the onset of dementia. This early hunch was substantiated by research he did as a PhD candidate, by which he discovered that there was a link between hemochromatosis and certain types of Alzheimer's disease. 

     In the following chapter, he states that "Parasites hunt us for our iron; cancer thrives on our cells. Finding, controlling, and using iron is the game of life. For bacteria, fungi, and protozoa, human blood and tissue are an iron gold mine" (6). Upon reading this statement, the book The Selfish Gene by Richard Dawkins came to mind. This publication similarly makes a rather weighty statement concerning one player, so to speak, belonging to a unfathomably large living system. In the moment of reading the statement that finding, controlling, and using iron was "the game of life", I was unsure whether it was hyperbole or simply an amazing fact, or if I was reading the entire thing wrong. 

     I tried to find some literature online about whether bacteria in general-- whether their entire life cycle-- was based on the obtainment of iron. The 2008 Science Daily article How Some Bacteria May Steal Iron From Human Hosts summarizes an effort made by a research team at Syracuse University to investigate how certain types of gram positive bacteria obtain iron from their environments. The lead researcher, Robert Doyle, comments that "iron is the single most important micronutrient bacteria need to survive" (SD). According to the article, iron is not easily accessible to bacteria living in soil or in humans. Much iron available in the soil is bound as "iron-citrate". With the knowledge that citrate was a substance that cells use as an energy source, the research team tried to uncover whether bacteria in human hosts also metabolized it. They discovered that some bacteria are equipped with a gene enabling the harvest of iron from human hosts in a "unique and energy efficient manner" (SD). Their experiments also demonstrated that citrate was ignored when it was not bonded to iron or bonded to other metals. 

     The article reinforced Moalem's argument concerning iron. I better understood his point that our dependency on iron gives a "proverbial leg up to just about every biological threat to our lives" (19).

Survival of the sickest?

      Survival of the sickest was, by far the most interesting read yet. It was well written and very engaging, however, I did find some of Moalem’s arguments to be taken out of context and reductionistic.  For example, he talks about the Younger Dryas and the evolution of diabetes and used very sound examples to support his hypothesis. However, he argues that more people are diagnosed with diabetes between November and February, than between June and September, which, according to Moalem, is “tantalizing evidence to bolster the theory”. I’m not sure that he sold me on this one; assuming every other factor involved with this statistic is held constant, this would be very “tantalizing” but that just is not the case. In summer months people are more active and metabolisms are in super-drive. Conversely, in winter months, people are generally less active and, in my case stuff my face, snuggle under the covers and watch oldies; it would make sense that more people are diagnosed with diabetes in the months where their metabolisms are less active.

        Another example that made me question Moalem’s theory was when he spoke of the evidence supporting the hemochromatosis theory and the link to the bubonic plague. This theory itself is very insightful and is filled with strong evidence supporting the link. However, one example that I had an issue with was when he claimed that men between fifteen and forty-four killed by the plague outnumbered women of the same age by a factor of two to one. He explains this by saying that women were spared because menstration caused them to have less iron and that children and elderly were malnourished, which subsequently caused iron deprivation. Prior to this statement he says that those thought to have the disease, witches and Jews were, at times burned -- people in those towns were obviously filled with panic and tried to find answers. I think the reason why men were killed more frequently by the plague than women and children, might of have had to do with iron, but was largely due to exposure. Since men were out working near, burying and burning infected people, I would think they were more vulnerable to contracting the illness, not necessarily more vulnerable to die from it.

       Also, what about all of the other diseases that plagued the human race, why haven’t we been protected from them? What about smallpox, the Spanish flu, cholera and typhus? are they so different from the bubonic plague? I think what makes the hemochromatosis-bubonic plague theory so compelling is that it fits… it originated just prior to the plague, which in my opinion helped establish the link. 

Survival of The Sickest

I have to admit I have no finished reading the book... I am just about to finish Chapter 5. However, what I have read so far is really interesting and a very easy read, yet confusing at times. I have 2 questions that I will address in this blog and if anyone can help me understand, that would be great.

First, on page 45, Moalem states, "When rats are exposed to freezing temperatures, their bodies become resistant to their own insulin. Essentially, they become what we would call diabetic in response to the cold." Okay, when I read that I interpreted it as "temporary diabetes". The following statement says, "In areas with cold weather, more diabetics are diagnosed in colder months... Children are most often diagnosed with Type 1 diabetes when temperatures start to drop in late fall." I understand that, too. Now here's my question; children diagnosed with Type 1 diabetes, would that be considered also a "temporary" diagnosis? That may seem like a foolish question, but the reading has not been able to answer that for me. I am curious to know how the children's blood levels are when temperatures are high.

Next, in chapter 3 page 64, Moalem writes, "heavy evolutionary pressure can breed a that into - or out of - a population's end pool in just a generation or two". That is really interesting, but it seems like he is making is sound a lot easier than what it really is. For example, the ACHOO syndrome; I understand it isn't heavy evolutionary pressure to get rid of it, but it seems kind of pointless now, right? Moalem even says it's very dangerous if someone is driving under a tunnel and has a sneezing frenzy when they get out. If this is something that has happened "way back when our ancestors spent more time in caves", wouldn't it not be in our genes? I guess I don't really have a direct question for this topic perhaps just clarification.

Does medicine influence evolution?

The Survival of the Sickest, by Sharon Moalem delves into the subject of evolution and why certain hereditary diseases continue to be passed on for generations regardless of their negative effects. It seems to me that as we develop more treatments for genetic diseases, evolution may slow down. This is because, if treated, many diseases do not prevent people from reproducing, or even living lives that are much shorter than a person without the disease. The same goes for any disease that may have killed people who were weaker than others. This is something that has fascinated me since I was in kindergarten and got Scarlet Fever. I had recently read the children’s book The Velveteen Rabbit, in which the little boy in the story dies of the very same disease. So, when the doctor told me what was wrong I immediately started crying, thinking I was going to die like the boy in the book. My mother then explained the concept of medicine, and how people generally do not die from things like Scarlet Fever anymore, and I felt better again in a few days. I do not know about studies that have been done on this subject, but I would be interested to read them. I am not quite sure how I feel about this idea because while evolution is important for our species to survive in the long run, I would not be willing to compromise the vast benefits of modern medicine and the strides they have made for people all over the world.

It also seems as though some genetic diseases, such as hemochromatosis are able to pass themselves in to offspring because they do not result usually in serious health issues until a person is older and could have already had children. For example, the author’s grandfather passed his hemochromatosis gene onto his children because he was not diagnosed with Alzheimer’s until he was 71 years old, long after his prime for having children. The gene has been passed on to his grandchildren and may be passed on to his great grandchildren in the same manner. I am also interested in the environmental factors that cause the genes for hereditary diseases such as the gene for hemochromatosis to express themselves. 

Maybe Being Anemic Isn't so Bad, but It Probably Is

In “Survival of the Sickest” Dr Sharon Moalem analyzes the relationship between the benefits diseases have had and the predisposition of these conditions in certain racial and ethnic groups. The relationship between race, genetics and disease is currently a very controversial topic, but Dr. Moalem is not shy to state facts about each of these topics and connect them. We had mentioned in class that Tay Sachs is one of the only diseases that seem to affect specific ethnic groups, but “Survival of the Sickest” lists a number of conditions and diseases specific to racial and ethnic groups and theories as to why they developed.

I had heard of a small portion of Caucasians being immune to AIDS, but wasn’t sure why or if it was even true. I have also often joked when at the beach with light skinned friends, that I don’t have to worry about skin cancer and sun block the way they do, my year long tan is a natural barrier, but wasn’t sure exactly why this was so. “Survival of the Sickest” is most interesting to me in that it analyzes everyday occurrences and common conditions as well as sensitive ones (the higher rate of hypertension among African Americans but not among Africans), in a plain and matter of fact way.

I heard a speech last semester in the NYU Sociology department about how drug companies are now selling drugs that target specific ethnic and racial groups. The speaker concluded that this was a result of the genome project cracking the human code and concluding that there is nearly no difference between any two human beings regardless of race. She stated that selling drugs which imply a difference does exist genetically is just an effort to further propel stereotypes and the belief that we are all different. Dr. Moalem describes the same fact, drug companies new racially based markets, from a more detached and unbiased position. Prevalence of a condition in one group and not another does have to stem from somewhere, and “Survival of the Sickest” offers theories of the origins of these conditions as being partially environmental, genetic and somewhat tied to ethnicity.

At least if there is another outbreak of the plague, my low iron count might help me survive an extra day according to Moalem. I had never thought to connect something as seemingly obvious as the abundance of life in green iron filled waters and bacteria feeding on the iron rich. Moalem’s theory makes sense, but I am not entirely sure I believe this particular theory, it seems over simplified and based and very little palpable research. 

Biology or Sociology?

“In Survival of the Sickest,” Dr. Sharon Moalem examines how many of the genes that cause detrimental diseases today can be explained by evolutionary processes. He argues that these now harmful genes could have been beneficial to a population’s survival at a previous point in time. This is why some people are pre-disposed to carry genes that cause diseases. For example, he discusses how humans who had diabetes were actually much less likely to freeze during the ice age. Or that people who produce too much iron were more likely to survive during the bubonic plague. Obviously now that we are not living in an ice age or time of plague, these genes are more harmful then helpful. The point is that they used to increase ones chances of survival, which is why they exist.

On the one hand I think that Moalem’s argument is an interesting account into why some populations are more pre-disposed to certain diseases. He makes a convincing argument that evolutionary factors could explain why Western Europeans are more likely to have the gene giving them too much iron, or why African-Americans are more likely to have higher cholesterol. I think society can unfairly to look down on people with these deficiencies as weaker members of the population who are somehow responsible for their disease. Moalem’s book clearly explains that many times, people are genetically pre-disposed to a certain illness because it would have actually been beneficial for them in a previous time period. African-Americans aren’t more likely to have higher cholesterol because of poor lifestyle choices, but because of an evolutionary process.

At the same time, I’m a little confused as to why we are reading this book for a sociology class. I’ve only read half the book so far, but it seems as though the author solely focuses on biological and evolutionary factors for why some people may be prone to a certain disease. I’m not criticizing the author for writing his book like this. Clearly he has a very specific point that he wants to stress; that diseases and genes that are detrimental to us today can be attributed to evolutionary factors because they would have been beneficial in a previous time period. However, it seems that for sociology, we would be focusing more on how social factors, not solely biological factors, effect people’s health today. I’m not saying that this book wasn’t valuable to read, I just feel as though it’s a little one-sided on the nature argument, and not enough on the nurture argument, at least for our major. 

Genes aren't what they used to be

The Survival of the Sickest by Dr. Sharon Moalem takes a look at different genetic issues and diseases and attempts to connect these issues to evolutionary factors and the history of the human race. The book presents how some disease that still effect us today like diabetes or even hemochromatosis are side effects of our evolution and although are troublesome today, were methods of survival for environmental issues like Younger Dryas and the plague.

What I found interesting was his link of hemochromatosis, an excess of iron in the blood, to Northern European survival to the plague. Apparently, those suffering from this issue have a lack of iron in their macrophages which causes their immune system to be able to better combat bacteria. Those with the genetic mutation were more likely to survive the mutation and pass this trait on to their offspring.  Certain environmental factors may cause traits to be more beneficial at a specific time than others, causing a sort of natural selection in humans to continue the lineage of those with a predisposition to beat whatever environmental threat in going on. He creates this same argument for diabetes and the great freeze that took places thousands of years ago, and how this trait that didn’t break down sugar gave the body antifreeze in this environmental time.

 Additionally, the same goes for bacteria. They also when given a threatened environment have a sort of natural selection.  The book notes that when penicillin was discovered, at first it treated staph, but eventually a percentage of staff infections were penicillin resistant. Just as humans were able to adapt to their harsh surroundings and reproduce offspring with genes for survival, so have bacteria. Just as we can use evolution to discover that natural selection has taken place so that species may survive and reproduce, we must also use that information to understand that by attacking bacteria in certain ways may speed along their natural selection evolution. Ewald was cited in this book stating that we should take control of their evolution by “favoring those mild strains and thereby domesticating those disease organisms, making them into mild versions of what they were before” (121). Through knowing our own history and evolution we should do what we can to not make bacteria stronger but to treat them in a way that would produce weaker versions of themselves.

The book through its examples of high cholesterol, hereditability, the Barker Hypothesis and others, what I gained from this book is that the human body is a complex system driven by primal forces to survive and reproduce.  Only when we trace what genes our ancestors used to survive in their harsh environment do these genes seem to be beneficial for us humans. Although we may understand some of nature and how our biological system works, the way in which we live our lives may not be the most beneficial. Just as what stress today isn’t dealt the same way as the Zebra running from the lion, certain issues in our body that could have been beneficial for us in the Savannah may not be as beneficial in the modern realm.

Zebras, Lions, and Humans? Interesting Mix

I was very interested in the book, Why Don't Zebras Get Ulcers when I first started reading it. I honestly had no clue how Sapolsky was going to incorporate zebras into this book and make a connection somehow with the human population and our society. There are a lot of stressors that humans and other mammals like us have everyday. These stresses are proven to cause sicknesses that can lead to diseases, terrible illnesses in fact. Although zebras and lion stress over entirely different things than humans do, the end result is usually the same. Chronic stress can cause a lot of cardiovascular issues in our population and it is entirely preventable. Obviously it is inevitable that we will have stress, however, according to Sapolsky, we humans like to think of a ton of scenarios in our head about things that went wrong in our day, how we are doing in class or at work, are we living up to societal standards, we think about or relationship issues, whether our family is doing well, if our house is clean, if we are safe, and many, many more things. All of these issues are grieved over to such an extent that it can actually cause us pain, to a point where we get illnesses over it.

Animals stress over things too. They have to worry about providing for their families, and if they are going to fall prey to another mammal higher up on the food chain, or if they are going to have something to eat tonight or somewhere to sleep. But animals have less chance of repeatedly, constantly worrying about these things. They are more of spur-of-the-moment occurrences and will likely be forgotten soon after. That is one of the main reasons that animals like that usually do not get serious side effects of stress like we do. However, if constant stress is placed on an animal, such as the stress that is placed on humans, than it is likely that the animal will experience an ulcer or something of the sort. For example, Sapolsky mentions a study that was done on a rat. The rat was frequently tossed around, forced to run back and forth and had it fight for its life. After the stress and exhaustion the rat experienced, tests were ran on it and they showed that the rat had a peptic ulcer.

Sapolsky is trying to make the point that in any of our organs in our body, stress can cause diseases to form inside of them. The same occurs in animals that experience the same stressful events. What shocked me was that social stress alone can cause the greatest damage in the blood vessels and arteries. Plaque can form and build up from the drama of not being accepted socially. The same was true for monkeys experiencing the same thing. The study showed that monkeys figure out where they stand socially with others of the same species very quickly and if this is not good to them then they get upset and stressed. The causes of hypertension and atherosclerosis come from this. Who knew that social stress could eventually cause so much harm?

Crazy Mind Causes Crazy Body

After reading "Why Zebras Don't Get Ulcers" by Robert M. Sapolsky, I think it is safe to say this book can definitely be judged by its cover. Beneath the title, the book admits that it is the acclaimed guide to stress, stress- related disease, and coping. One of Sapolsky’s insights on the issue of stress is that unlike zebras who deal with stress fast and furious followed by a continuation without worry, human beings dwell on their stress and the anxiety of anticipating additional stress can be very damaging to one’s health. One of the most interesting concepts that I found in the book was the effect of the nervous system on the immune system. I was drawn in by this discussion due to my own personal experience of waking up with a headache and then convincing myself for the rest of the day that I am more sick than I am until I actually develop flu- like symptoms. I knew I was just psyching myself out, but this book really called me out on my neurotic behavior and explained how interconnected the brain and the immune system are. In order to demonstrate the relationship, an example of waving an artificial rose in front of someone highly allergic to roses and consequently they would have an allergic reaction even though the flower was a fake. The book admits that this test is a bit dated, but follow up studies have reinforced the point that thinking influences feeling, so the theory stands true. I have to admit I was a bit freaked out that maybe my mind was too controlling over my feelings and perhaps the first time I felt overly happy or sad was because my brain was influencing my body. Can we now ever know for sure if what we are feeling is organically the real deal? 

Save Us, George Clooney

The principal argument of Dr. Robert M. Sapolsky's thoroughly entertaining book Why Zebras Don't Get Ulcers is that stress is bad for our health because it makes us more vulnerable to diseases, such as heart disease or even arthritis.  Sapolsky's book focused mostly on the physical element of stress, what exactly is going on chemically in the body to cause stress, but I am more interested at the concept of stress as a determinant to health in general.  Typically when we consider the causes of illness, we point to a known physical causation, such as an infection by bacteria, lack of sleep, or getting a chill on a rainy day.  But in the case of stress, the "stressor" is not something that is tangible, and almost exclusively affects our psyche.

Examples of stressors include the ending of a relationship, losing a job, or an approaching exam.  The way our bodies react to these stressors is what makes us vulnerable to disease, and that got me thinking about ways that these stressors might be made less stressful.  Personally I think that losing one's job is an extremely stressful event, in fact it has been put on par with the death of a family member in terms of stress.  George Clooney in the film "Up in the Air" plays a consultant whose job is to go into a company that is downsizing and fire people.  I'm not about to suggest that companies get Hollywood A-listers to fire people to smooth things over, stay with me.   Part of the process is that Clooney gives everyone who is being fired a packet with information about what to do next, including references and good ideas about where to go next for employment.  While many companies do things like this already without a third party, I think it is extremely important, particularly in light of discoveries about the impact of stress on one's health, to create ways to make a stressful event like being fired as painless and hopeful as possible, for the good of the employee and the work force as a whole.  Happy, healthy workers do good work. 


Another interesting idea about how to reduce stress with stressors (probably a better way to say that) is this Dutch hotel, who is offering a service that allows couples to go through the entire process of a divorce in just a couple of days, rather than dragging the process out for months and months.  This seemed relevant to me because of Sapolsky's statement that what makes stress so bad is how long it can last, and perhaps something like this would be extremely useful to couples looking to divorce.  Not very festive with Valentine's Day coming up, but I hope you found it as interesting as I did.

Intersections of Biology and Sociology

When I first approached Why Zebras Don’t Get Ulcers I was skeptical. I thought that the idea that stress could cause illness was an excuse used by doctors to explain illnesses that they couldn’t find a specific cause for. However, Sapolsky makes a very convincing argument in this book that stress does in fact play a role in the illness process. However, he is careful to point out, “it is never really the case that stress makes you sick, or even increases your risk of being sick. Stress increases your risk of getting diseases that make you sick” (16).

Although this may seem like an insignificant point, Sapolsky brings it up again in the beginning of Chapter 17, when he discusses how social status can affect health. He describes two camps of thinking about poor health with biomedicine on the one hand full of people who think that “poor health revolves around issues of bacteria, viruses, genetic mutations, and so on” and on the other hand “folks anchored in mind-body issues, for whom poor health is about psychological stress, lack of control and efficacy, and so on” (353). He criticizes both of these extremes and instead argues that biological disease must be considered within a personal and social context.

I thought that this was a compelling argument and it reminded me of what I thought one of the main arguments of The Starting Gate was, namely that we would benefit from considering the ways in which biology and sociology intersect with one another. As a pre-med, biology major, I think that I often tend to side with the reductive biology extreme and am skeptical of social explanations for illnesses, but this book has opened up my point of view and helped me to understand how social factors like stress can indirectly lead to illnesses through biological processes. 

Mind Over Matter?

I would like to focus on the interesting topic of "mind over matter" and the ever-present problem of placing too much emphasis on one factor over another. It can be an incredibly helpful thought that our minds can control our physiological state and can be empowering for those who feel they do not have control over their biology or have the exact opposite example.

One really interesting example I found of this is the yoga/meditation technique called Tum-mo that has been studied for its affect on physiological state. Here is the link to an article from the Harvard Gazette (from 10 years ago) about a study done by Herbert Benson on Tibetan monks practicing Tum-mo. Benson states (in the above article) that he is interested in studying advanced forms of meditation since he believes that they, "can uncover capacities that will help us to better treat stress-related illnesses".

This idea I think is interesting to think about in relation to this whole big book about stress-related illnesses. He has developed the "relaxation response" which is essentially the opposite physiological state of stress and, "it is characterized by decreases in metabolism, breathing rate, heart rate, and blood pressure". I thought this was interesting in light of the book. Any thoughts on his idea?

Also, he said in the article that he was planning on trying it out again the following winter. However, I was unable to find (if anyone wants to try looking, feel free to do so and share!) information about another attempt. I did however when looking him up find that he has since then written somewhat extensively on the health benefits of prayer.

Another interesting case is that of Wim Hof known as the "Ice Man" who essentially runs shoeless and shirtless in freezing temperatures and attributes this ability to his practice of Tum-mo. Here is a discovery channel video about him (I didn't watch all of it, but if you are interested in his story check it out). Hof (who holds 18 world records) has climbed Kilamanjaro in 2 days wearing only his shorts and can remain immersed in a bath of ice for 1 hour and 44 minutes. He also published a book recently (November 2011) called, Becoming the Iceman.

If anyone is interested in reading more about scientific studies of Tum-mo (including Benson's actual study)

Benson et al. (1982) Body temperature changes during the practice of g Tum-mo yoga., PDF: http://lib.semi.ac.cn:8080/tsh/dzzy/wsqk/Nature/295-234.pdf

Ding-E Young, John and Taylor, Eugene (1998) Meditation as a Voluntary Hypometabolic State of Biological Estivation, PDF: http://physiologyonline.physiology.org/content/13/3/149.full.pdf

That was the mind over matter is awesome and super cool portion. Now here comes the negative side. The book mentions Bernie S. Siegel and his book, Love, Medicine and Miracles (New York: Harper & Row, 1986). The main point of the book is that, "the most effective way of stimulating the immune system is through love, and that miraculous healing happens to patients who are brave enough to love" (178). Sapolsky explains quite well what the problem with this view is:

"No matter how often he puts in disclaimers saying that he's not trying to make people feel guilty, the book's premise is that (a) cancer can be caused by psychosocial factors in the person; (b) cancer (or any other disease, as far as I can tell) is curable if the patient has sufficient courage, love, and spirit; (c)if the patient is not cured, it is because of insufficient amounts of those admirable traits. As we have just seen, this is not how cancer works, and a physician simply should not go about telling seriously ill people otherwise" (179).

This is an incredibly dangerous viewpoint that can essentially have the disempowering effect of making patients feel responsible for their illness. Illness can be incredibly stressful and this blames those who aren't getting better and accuses them of not having the right attitude to get better. There are plenty of people who have the 'right' attitude but don't get better and this could make them feel defeated.

There is obviously a lot more about this that could be said, but, I wrote way more than 300 words and would rather hear what other people have to say about it.

Stress Always a Bad Thing?

“Why Zebras Don’t Get Ulcers” by Robert M. Sapolsky is a fascinating book that talks about the affects of stress on the human body and all the stress related diseases that harm our health. Sapolsky points out that humans are not meant to live in cities but instead in the wild where our stress responses would be detrimental to our survival. Instead, our bodies have to consistently recover back to the homeostatic balance after a stress response, which tends to harm the body. Before reading this book I knew that studies show that stress has a good deal to do with ulcers but I did not know it contributed to so many other diseases.

Sapolsky has gained a great deal of his knowledge on the effects of stress by studying wild animals in Africa. One quote from the book that I found interesting was that humans “can get stressed simply with thought, turning on the same stress response as does the zebra.” He further states that no other primate can get stressed by thought. How we were able to develop the ability to get stressed out by thought is the first time I heard of a bad side effect from our increase in intelligence throughout the centuries. He does state that maybe if humans were smart enough to develop it maybe we will be able to find a way to get rid of it. However, I believe that even though stress may hinder our body, it is also something that motivates us and helps us complete our responsibilities. Of course I do not believe stress on a large-scale basis is good because I do know of many people that suffer from anxiety. But, when controlled, I believe that stress can be a good thing that helps our efficiency and keeps us on track.

Stress

Until reading Robert M. Sapolsky's Why Zebras Don't Get Ulcers, I did not realize how easily stress and its detrimental effects plague us. Just with our thoughts and not moving a muscle, we can mess with our body's homeostasis. Our thoughts can trigger our organs to secrete hormones as a response to the stressor and spark a chain reaction of responses throughout our body. I used to always attributed stress as a good thing which helps push and motivate me. However, the book proves to us that perpetually being in a stressful state is bad for our health in the long run. This shows that while a short-term stress may be healthy, constantly being stressed and worried is not good for us. It surprised me to read that due to stress our immunity will be inhibited and our body will delay in finding things such as tumor cells and delay producing antibodies to protect us. The stress response can be more harmful than stress itself. A stressful thought can be likened to a prey running away from its hunter. It puts our bodies into overtime and can affect us by causing the blood to rush through our veins and arteries creating more muscles around these blood vessels, which is bad for us and may cause cardiovascular diseases for us in the future. Regardless, sometimes there are people who may go through the same stressful situation but some of them may not develop a cardiovascular disease due to their personalities and some may already have a damaged cardiovascular system which the stress will hurt them more. It was also interesting to see that when woman produce estrogen at a younger age, it is more likely to protect them against cardiovascular diseases. I find it really interesting that our body has unique responses to certain situations but long-term stress will have harmful repercussions.

Stress and Memory

In his book, Why Zebras Don't Get Ulcers, Dr. Robert Sapolsky discusses the various mechanisms by which stress induces illness in human beings.  Sapolsky, a professor of neurology and biological sciences at Stanford University, highlights the key differences in the stress responses between humans and their animal counterparts, ultimately relaying the message that we make ourselves sick.  

structure of glucocortiod

The section of Sapolsky's book that I was particularly interested in was Chapter 10, "Stress and Memory."  Here, he discusses the effect of the class of steroid hormones, glucocorticoids, on the brain.  In the healthy body, these steroid hormones play an important role in metabolic, immunological, developmental, and cognitive processes. At abnormally high levels, glucocorticoids disrupt a person's ability to store new memories.  Stress is among several possible causes for increased glucocorticoid levels.  Other possible causes for these abnormal levels are Cushing's syndrome and treatment with steroid anti-inflammatory compounds that contain synthetic glucocorticoids.

Perhaps the most interesting part of stress-induced memory disruption is the brain's ability to highlight emotionally traumatic memories, such as those experienced by an individual with PTSD.  While Sapolsky explains that most humans are vulnerable to the negative consequences of stress, I found it particularly intriguing to understand how stress in extreme proportions can have permanently damaging effects on the brain and health. 


(Also, there is a PBS called "This Emotional Life," featuring Dr. Sapolsky, that included a segment on PTSD. )

Zebras and Stress

In Why Don’t Zebras Get Ulcers, Stanford Biologist Robert Sapolsky examines how human patterns of disease have evolved over time through the lens of stress. Earlier generations preoccupied themselves with infectious diseases such as malaria and bubonic plague, as well as diseases stemming from poor nutrition and hygiene. In contrast, we are now plagued by diseases that are “ones of slow accumulation of damage - heart disease, cancer, cerebrovascular disorders”. Modern medicine has come to recognize that extreme emotional disturbances can adversely affect both physical and mental health, and many of these slow accumulation diseases have been linked to stress. What this book does well is to serve primer on stress, its biological components and how our body reacts to and deals with stress.

The biggest thing I took away from Sapolsky’s book is really just how complicated of a system the human body is. Indeed, many of the stress-related diseases that Sapolsky dissects come not directly as a result of external stressors to the human body, but rather are caused by the body recovering from the counter-measures it put into place to deal with stress. For decades, scientists and doctors believed the ulcers were directly caused by the bacterium helicobacter pylori, but more recent research reveals that stress is one of the key factors in the formation of ulcers. One theory, called acid-rebound, posits that your stomach cuts back on acid secretion during long stressful periods - because digestion is being inhibited. Because less acid is being secreted overall, your stomach decides to save energy by cutting back on the systems that are in place to keep the stomach from digesting itself. But once the stressful period is over, your stomach gets flooded with acid and does not have as strong as defenses to protect itself. After several cycles of this rebounding, ulcers form in the stomach.

It seems as though in order for the human body to adequately deal with stress, the brain needs to carefully regulate how it is releasing hormones and glucocorticoids. It needs to keep everything in a delicate balance, this is the essence of the idea of allostasis that Sapolsky refers to throughout the book. I believe that this book functions very well as a primer on stress and stress-related diseases. It breaks down the biological, physiological, and psychological components of stress in a easy-to-understand yet well thought-out manner. The constant reference back to scenario of a zebra running away from a lion on the Savannah works well as a metaphor, as it demonstrates that, while the body’s stress-responses work incredibly well out in the wild, they have much less desirable effects if they continue to act over long periods of time.

-Jon Wei

Intergenerational Transmission and Race

I thought the data on the intergenerational transmission of low birth weight and the discussions about LBW versus race were particularly very interesting. The book stated that intergenerational transmission can be attributed to biological and possibly even genetic causes (60). There is talk about how if the mother from a previous generation was born of low birth weight, or had a sister who was born with low birth weight or the mother, there is an increased chance of her child being low birth weight. This makes me conclude that there is a genetic factor involved in low birth weight and it plays a pretty significant role. It may even tell us that there is a specific gene or something that is passed down within certain people in the family that can contribute to a baby being of low birth weight. Additionally, it is noted that social, economic, and behavioral conditions are shared so those may contribute to the low birth but cannot have such a direct effect or causation. They also found, while factoring out a lot of other factors such as mother, behavior, SES, race, etc, that families that have a father who was low birth weight have an extremely high potential of being of low birth weight as well. Which is odd, seeing as one would think the opposite with the mother. This leads to the fact that maybe there is some sort of recessive gene for low birth weight or something along those genetic lines.

One factor that cannot be ignored in this intergenerational research is the race of the child. Race was discussed in this book quite a lot even in the opening chapters. It is a very imminent problem in the research of low birth weight children and begs an answer. How much does race really have to do with the lo birth weight of a child? Race can determine a lot of other factors in the child's life as well, so this is one of the main reasons why researches think it to be so prominent. There was comparison between African American babies and non-African American babies in the first few chapters that touched on why African American babies were an interesting circumstance. There are a lot of African American families, actually more of them who are lower in socioeconomic status than non-african Americans. Even the ones who are middle and high class and very successful were stated to have on average more low birth-weight babies. This discredited the theory that the cause for the low birth weight was the socioeconomic status and the wealth and quality of the jobs that these families had. Although these factors do play a big role. If the family is not living in a great place and it is run down, they do not have steady jobs or good health care, which a lot of African American families don't, then they will not be able to raise a baby, even in the womb, with a healthy, productive lifestyle. There won't be a way for the baby to get good prenatal care and they won't be able to provide for it. However, the book did state that some black babies may just be naturally smaller than white babies are at birth, which would explain the statistic of frequent low birth weight. Black babies may be smaller at all gestational stages (45). Therefore, race does not show any causation, or even a good correlation for low birth weight because a black baby being small does not have the same negative implications for development.