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Friedrich Leopold August Weismann

640px-August_Weismann

Educational Background/Training

Weismann was born on 17 January 1834 in Frankfurt am Main, in the German Confederation. His mother, Elise Eleanor Lübbren, was a musician and painter, and his father, Johann Konrad August Weismann, was a classics professor. Weismann studied music, particularly the works of Beethoven, and he studied nature, from which he collected butterflies. He noted diverse patterns and colors of butterflies, information that later informed his research on the development and evolution of butterflies and caterpillars.

In 1856 Weismann got his medical degree from the University of Göttingen in Göttingen, in the German Confederation. After graduation, Weismann worked as an assistant in a hospital for three years in Rostock, in the German Confederation, before becoming a physician in Frankfurt am Main in 1859. From 1861 to 1863, Weismann was the private physician for Archduke Stephen of Austria. In 1861, Weismann studied at the University of Giessen in Giessen in the German Confederation, with Rudolf Leuckart for two months, working on the ontogeny (development) and morphology (form) of animals, insects in particular. That year, Weismann read Charles Darwin’s On the Origin of Species two years after it was published in 1859, after which he adopted evolutionary theory. Weismann studied different factors he thought might cause morphological transformations in insects, including natural selection.

In 1863, Weismann became a docent in zoology and comparative anatomy, a mid-ranking academic position, in the University of Freiburg in Freiburg in Breisgau, also in the German Confederation. In 1864, Weismann’s eyesight declined, which left him partially blind and limited his ability to use microscopes. Nonetheless, he studied the metamorphosis and development of butterflies. Weismann became the founding director of the Zoological Institute at the University of Freiburg in 1867. That year, he married Marie Dorothea Gruber from Genoa, Italy. The couple had at least five children. Along with his students and assistants, Marie aided his experimental and observational studies after his eyesight failed. Marie died in 1886, but Weismann remarried at the age of sixty in the mid-1890s to Willemina Tesse from the Netherlands, a marriage that lasted six years.

Summary of Research

            August Friedrich Leopold Weismann studied how the traits of organisms developed and evolved in a variety of organisms, mostly insects and aquatic animals, in Germany in the late nineteenth and early twentieth centuries. Weismann proposed the theory of the continuity of germ-plasma, a theory of heredity. Weismann postulated that germ-plasma was the hereditary material in cells, and parents transmitted to their offspring only the germ-plasma present in germ-cells (sperm and egg cells) rather than somatic or body cells. Weismann also promoted Charles Darwin's 1859 theory of the evolution of species. Weismann argued that only changes to the germ cells, and not body cells, could be inherited, a theory that influenced theories of heredity throughout later centuries.

From 1881 onwards, Weismann published a series of essays about heredity. Those essays were collated in English in 1889's Essays upon Heredity and Kindred Biological Problems. The essays discussed topics including senescence, acquired characteristics, and the germ-plasma theory. For example, in the first chapter, "The Duration of Life," a translation of an essay originally published in German in 1881, Weismann detailed his evolutionary theory of senescence, the name given to the gradual deterioration of function of most life forms after they mature to adults. Weismann argued against theories that associated the length of an organism's life with the size or complexity of its body, or with how active it appears to be. Instead, he appealed to natural selection, arguing that it adapted organisms to reach reproductive maturity, and that it would not select for the capacity of the organism to live any longer once it was past reproductive age. He further argued that the death of male bees after they reproduced was selected for by nature to save nutrition for the colony, a phenomenon that precluded those organisms that had already reproduced from consuming resources.

Linking his work to broader context

When Weismann’s germ theory is paired with that of Gregor Mendel’s on inheritance we are provided the basic understandings of how humans and other animals inherit their traits from their parents. Weismann used his germ theory to explain that, “natural selection favors organisms that pass on their germlines before conspecific and before extrinsic factor cause their death (Crews and Ice, 2012: 639).” This statement has been used to create the concept of life history theory for many different species, including humans. For life history theory, we see that the goal to reproduce is in conflict with the maintenance of the body. This result in trade-offs that the body goes through in order to chose one of these actions over the other. The allocation of resources between reproducing and somatic maintenance created a way for researchers to compare and to structure their research as to why these chronic diseases and changes in old age occur. Through these trade offs in life history theory is how Weismann can be connected to this chapter. This chapter discusses the aging and senescence of humans. Senescence occurs when the body begins to function less efficiently and cell begins to functioning deteriorate as life progresses. The chapter discusses the different ways that the body ages in multiple areas, including hormones, immune system, cardiovascular, body composition, bone, dementias, and reproductive aging. All of these areas are altered through the aging of an individual based on the life history course that has been taken. One problem with Weismann’s concept of life history is that it does not allow for the environment and culture to alter these stages. Even in the chapter there is little discussion on the environment and its effects on life history. Yet, with the time that Weismann came up with this theory there must be credit given for his ability to come up with these conclusions that further lead to our understanding of how the body works.

Crews, D.E., Ice, G.H. (2012). Aging, senescence, and human variation in Human Biology: An Evolutionary and Biocultural Perspectives, Second Edition. Edited by Stinson, Bogin, O’Rourke. John Wiley and Sons, Inc.: Hoboken, New Jersey.

(2008). August Weismann found at http://www.encyclopedia.com/topic/August_Weismann.aspx.

Aging and senescence are two concepts of biological evolution that usually occur simultaneously. Aging is an inevitable process among all humans and animal species. The survival method and length may be different, but the body’s equipment will begin to deteriorate with time. Time is a process that cannot be reversed biologically or socially; therefore the body adapts overtime to such processes. In this, how the body is treated over time will result in rapid or reduced aging. The body will still age, but the rate of deterioration will be decreased. All of these mechanisms play into all bodily functions, the only separation is depending on the person, their diet, their physical activity and genetic makeup.

One in every 100,000 persons survive as long as 120 years old. Most men and women will not live to see this age. The average age for men before developing signs of senescence in 70 years old. At 70 years of age, Alzheimer’s and other degenerative conditions began to take its peak conditions. As mentioned earlier, the life conditions are based on the individual and his or her lifestyle. In an article entitled, “Late Life Human Development: Boosting of Buffering Universal Biological Aging” Kolling and Knopf introduces biological aging and senescence by describing telomere length (TL), theories of aging (evolutionary, stochastic, and deterministic), and free radical involvement.

In evolutionary aging theories, Weismann elaborates upon the idea of natural selection. This theory promotes Darwin’s ideas, but also the idea of group selection. Group selection states that aging benefits the group, even though it may be detrimental to the individual. He later proved this theory to be discrediting and presented the idea of disposable soma theory instead. This theory states that the organism separates germ and soma in order to maintain reproductive power due to evolutionary pressure. We all know this to be true, seeing as if the soma cells are all other cells other than the reproductive cells, and that reproduction only takes place during a certain lifespan, and it is not presented as an opportunity after a certain age in certain groups of men and women. Moving along, stochastic aging theory relies on the core idea that while individuals age, a significant amount of biological damage is accumulated over time in a random fashion as a by-product of normal living. My favorite of the three stochastic theories is the “wear and tear theory”. It proposes that the usage of the body and over time, cumulative damage occurs within the body leading to death of cells, tissues, organs, and finally the organism itself. Next, the “free radical theory” expounds upon how free radicals are produced during aerobic respiration later causing rapid death. These radicals place a threat to the aging organisms because of oxidative damage.

Finally deterministic aging theories presume that aging occurs because of genetically and endogenously programmed processes. One example is the absolute metabolic scope theory. This is a rather old theory which states, that the greater an organism’s oxygen basal, the shorter the lifespan. In all of these theories, they relate to telomere length of an individual’s chromosomes. In a study, longer telomeres at baseline were associated with reduce risk of death and dementia; however, research on the associations between telomere length as a predictive biomarker of mortality is still controversial.

Kolling, T., Monika Knopf (2014). "Later Life Human Development: Boosting or Buffering Universal Biological Aging."' GeroPsych Review. vol 27. (3), 103-108.

The body is a complex mechanism among both female and males. The growth of the human body depends on many factors including, the embryo stage, puberty, and physical activity among the growth years. In order for a body to progress/growth successfully, it must reach maturation biologically. This development promotes growth maturation for the remainder of one’s life in regards to future physical activity and performance. These activities dominate the daily lives of men and women. Based on the rate of growth in bones during embryonic development, the body will grow at the correct rate to produce a full body with full length bones. In the article entitled, “Top 10 Research Questions Related to Growth, Maturation, of Relevance to Physical Activity, Performance, and Fitness” Robert M. Malina explains the growth, body mass index, motor competence, peak height velocity, and tracking of infants, children, and adolescents. Adulthood will also be explained in correspondence to future maintenance of healthy bones and physical activity.

The cellular processes that underlie biological growth and maturation as well as other behavioral aspects cannot be measured directly; however, advances in technology are providing significant insights. Research and standardized tests have help to unpack growth in height, weight, and the stage of sexual maturity. Biologically, most girls are sexual mature by the age of 12 and boys by the age of 14. This maturity is solely biologically. Social maturity based on societal standards is reached by the age of 18 or 21. Height and weight are the body dimensions most commonly used to monitor growth. With age, children are expected to become taller and wider, unless otherwise deemed to be ineffective by disease. Such disease may alter the length of bones and their maturation. This in turn will also affect the physical activity and inactivity of adulthood. Trend in physical activity have been measured on boys and girls of the age 13 and 14. Researchers examined school sports, daily leisure, eating habits, and physical endurance. These performances explain the leading questions regarding growth, fat mass, BMI, and other measureable adipose tissue quantities.

Most recent surveys are based on moderate to vigorous activity (MVPA). The focus of the questions addressed is the amount and type of physical activity needed to bring about beneficial effects. Question 1: Is regular activity essential to support normal growth and maturation?  For the most part, studies show that youth who regularly engage in physical activity seem to have less adiposity (skinfolds, percent fat) than do those engage in less activity; however, enhanced activity programs as in interventions appear to have minimal effect on adiposity in normal weight youth. Question 2: Is BMI the most appropriate metric for overweight and obesity in youth? Question 3: What is the implication of the “adiposity rebound” for subsequent weight status and physical activity? Question 4: What is the role of physical activity in the prevention of “unhealthy weight gain” during childhood and adolescence? Researchers believe early childhood and the transition into middle childhood may be important windows of opportunity for intervention to limit excess weight gain. Maintenance of smaller gains in BMI and FM through regular physical activity over time thus has the potential to prevent unhealthy weight gain as well. Question 5: Is there a critical level of movement proficiency that facilitates physical activity and sport participation in children and adolescents? Motor skills and movement proficiency do go hand in hand, however the transition between each child may be different. The remainder of the five questions continues to address physical activity and growth, but obesity becomes the center of exploration.

Malina M. R. "Top 10 Research Questions Related to Growth and Maturation of Relevance to Physical Activity, Performance, and Fitness. (2014). Research Quarterly of Exercise and Sport. 85.157-173.

The chapter this week was all about stress and reminded me of one of our very own professors here at University of Alabama, Dr. Dressler. His work on cultural consonance and its connection in African Americans in Alabama and higher blood pressure levels is actually mentioned in the chapter we read. The chapter discussed how blood pressure and depression are some of the responses that occur from stressors. The article I decided to look at was “Does perceived stress mediate the effect of cultural consonance on depression?” In the article the researchers, Mauro Balieiro, Manoel Antônio dos Santos, José Ernesto dos Santos, and William Dressler were interested to see “does stress appraisal, as measured by the PSS, mediate the effects of cultural consonance on depressive symptoms? (Balieiro, Antônio dos Santos, Ernesto dos Santos , Dressler, 2011: 532).”

In the article, the study takes place in Ribeirão Preto, Brazil, looking at four different neighborhoods with varying socioeconomic status (SES). The four communities SES are lower class, lower middle class, traditional middle class, and upper middle class. There were four cultural domains that they were researching, including lifestyle, social support, family life, and national identity. To identify parts of the domain participants were asked to free list terms or things that are important to that domain, such as “ what things are important to have to live a good life? (Balieiro, Antônio dos Santos, Ernesto dos Santos , Dressler, 2011: 526).” This provides the investigators with many terms, these were then narrowed down to 20 to 30 terms that exemplify the cultural domain. Participants were then told to take these terms and sort them into piles based on similarities. Also participants were asked to rank order these terms from most important to that domain to least important. Depressive symptoms were measured using the Brazilian Portuguese version of the Center for Epidemiologic Studies Depression Scale. Perceived stress was measures using Cohen’s Perceived Stress Scale (PSS) that was translated into Portuguese. Three covariates were used, including age, gender, and SES. All tests were done during two separate time periods.

The results show that “the effect of cultural consonance in lifestyle is reduced to statistical non-significance (p<.10) when PSS is controlled (Balieiro, Antônio dos Santos, Ernesto dos Santos , Dressler, 2011: 531).” Also it was found that “the effect of cultural consonance in family life on depressive symptoms that is mediated by the PSS is statistically significant (z=2.75, p<.01) (Balieiro, Antônio dos Santos, Ernesto dos Santos , Dressler, 2011: 532).” It has been found that the being cultural consonant in a domain and being unable to obtain this results in depression in individuals. From these results it was concluded that the PSS somewhat resolves the depression that occurs from cultural consonance. This suggests that more research should be done, specifically looking at other cultural domains.

Balieiro, M.C., Antônio dos Santos, M., Ernesto dos Santos, J., Dressler, W.W. (2011). Does perceived stress mediate the effect of cultural consonance on depression?. Transcultural Psychiatry, 48 (5): 519-538.

 

This weeks' reading revolved around stress on the human body. These blueprints to hormone level production, neuron response, and the neurological development was displayed in a case study by Aaron Kindsvatter and Anne Geroski. In this article entitled, “The Impact of Early Life Stress on the Neurodevelopment of the Stress Response System, they present a study with both an animal model and humans. This article is used to describe the functioning of the stress response system of the brain and to review literature pertaining to the impact of early life stress on the development of the stress response mechanisms.

The primary mechanisms of the stress response system include the sympathetic-adrenal-medullary axis (SAM), the limbic system and the hypothalamic-pituitary adrenal axis (HPA). The SAM axis involves direct connection between the norepinephrine center of the brain stem and the adrenal glands and is associated with the activation of the sympathetic branch of the autonomic nervous system. Most would also refer to the system in regards to the para-sympathetic nervous system in reference to a “flight or fight” response. Under this division of the autonomic nervous system, this response also helps to regulate homeostasis and allostasis. The HPA plays a key function in stress response by initiating a series of neurotransmitters and Nero hormonal cascades that, among other functions, serve to regulate the body’s response to stress.

These researchers used both rats and cats as control groups to help correlate stress among early development to adult hood. Among the cats, they inhibited some of the cats from using their right eye upon birth. In this they found that these now grown cats developed conditioned eye sight even after eye sight with both eyes were permitted. This carried on neuro-response was also relate able to maternal instincts among mothers of human under post and prenatal stress. Among this study, the same results among the cats and rats were valid. These lasting effects per-conditioned the brain to produce more stress relieving hormones. More ACTH and CRF resulted in the diagnosis of PSTD. This study was also compared to cortisol levels of adult survivors of child abuse. Within all of the new found diagnosis, the idea of threat experienced at an early age resulted in lifetime effects of such bodily productions to counteract future threats.

In all, the body’s response to previous witnessed ideas of threat will promote certain synaptic response with different levels of hormone production; hence, why some people experience strokes more rapidly. Stress can cause major body dysfunctions. It is even one of the leading cause of death in the U.S. Stress will condition the brain to adapt to certain experiences at certain times, without this modification through early stress level identification, the explanation of stressful adulthood might be still in question.

Geriski and Aaron Kindsvatter (2011). "The Impact of Early Life Stress on the Nuerodevelopment of the Stress Response System". American Counseling Association.

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John Snow "Father of Modern Epidemiology"
John Snow "Father of Modern Epidemiology"

John Snow, born in 1813, was the son of a coal-yard laborer in York, England. Snow planned to become a physician, and at fourteen, he was apprenticed to Dr. William Hardcastle. During his early years as an apprentice, he filled notebooks with his thoughts and observations on scientific subjects. In the summer of 1831, when Snow was eighteen and in his fourth year as an apprentice, an epidemic of cholera struck London. The disease, which had already killed hundreds of thousands of people on the European continent, spread north to Newcastle in October. The first symptom of cholera was queasiness, followed by stomachache, vomiting, and diarrhea so profuse that it caused victims to die of dehydration.

Dr. Hardcastle had so many sick patients that he could not personally see them all, so he sent Snow to treat the many coal miners who had fallen sick at the Killingworth Colliery. There was little that Snow could do to help the stricken miners, because the usual treatments for disease- bleeding, laxatives, opium, peppermint, and brandy -- were ineffective against cholera. Snow continued to treat cholera patients until February of 1832, when the epidemic ended as suddenly and mysteriously as it had begun. By that time, it had left fifty thousand people dead in Great Britain.

During the next sixteen years, Snow earned an M.D. degree, moved to London, became a practicing physician, and distinguished himself by making the first scientific studies of the effects of anesthetics. By testing the effects of precisely controlled doses of ether and chloroform on many species of animals, as well as on human surgery patients, Snow made the use of those drugs safer and more effective. Surgeons who wished to anesthetize their patients no longer risked killing them by the unscientific application of chloroform-soaked handkerchiefs to their faces.

Snow began to do a lot of thinking about the possible causes of contagious diseases, and he came to the unconventional conclusion that they might be caused by invisibly tiny parasites. This was not an original idea, but it was an unpopular one during the first half of the nineteenth century. The "germ theory" of disease had first been proposed in ancient times, and the discovery of microscopic organisms in the late 1600s had made the theory seem plausible, but no one had ever proved that miniature organisms could make people sick.

In Snow's day most physicians believed that cholera was caused by "miasmas" -- poisonous gases that were thought to arise from sewers, swamps, garbage pits, open graves, and other foul-smelling sites of organic decay. Snow felt that the miasma theory could not explain the spread of certain diseases, including cholera. During the outbreak of 1831, he had noticed that many miners were struck with the disease while working deep underground, where there were no sewers or swamps. It seemed most likely to Snow that the cholera had been spread by invisible germs on the hands of the miners, who had no water for hand-washing when they were underground.

Title page of Snow's pamphlet

In August of 1849, during the second year of the epidemic, Snow felt obliged to share what he considered convincing evidence that cholera was being spread through contaminated water. At his own expense he published a pamphlet entitled On the Mode of Communication of Cholera. Thirty-nine pages in length, the essay contained both a reasoned argument and documentary evidence to support his theory. As one example he cited the case of two rows of houses in a London neighborhood that faced each other. In one row many residents became cholera victims, while in the other row only one person was afflicted. It was discovered, Snow wrote, that "in the former bowl the slops of dirty water, poured down by the inhabitants into a channel in front of the houses, got into the well from which they obtained their water." Snow realized that such conditions existed in many neighborhoods and that if cholera epidemics were ever going to be eliminated, wells and water pipes would have to be kept isolated from drains, cesspools, and sewers.

Snow's research remains extremely relevant today, necessitating sanitary septic infrastructure in any populated area. The pathogen Vibrio cholerae is not contagious from body to body but is easily spread through food and water sources that become contaminated with sewage. The conditions necessary to induce a cholera outbreak still exist in many countries where hygienic water sources are not readily available. The largest outbreak in modern history occurred months after the 2010 Haitian earthquake. 6,631 deaths were recorded among the 470,000+ reported cases. The Centers for Disease Control and Prevention (CDC) soon went to work, establishing guidelines for cholera treatment and avoidance as well as setting up sanitation facilities. $75 million has been spent by the US government in attempts to control the disease but Haiti will likely continue to have increased cholera transmissions far into the future. Educating people in hygienic practices can only go so far. Efficient water and sewage infrastructure is vital to reducing the impact of the disease. John Snow was the first to recognize the importance of a clean water supply after investigating the cholera outbreaks of 1800s London. His work was the first step into requiring strict government and city maintenance of water resource structures.

 

 

Sources:

Father of Epidemiology

Haitian Cholera Outbreak

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Human epidemiology is the study of disease, its contributions and disparities, and potential ways to help stop the spread of disease. Among the West, there are many different diseases, viruses, prions, and other contagions that are incurable. Even among all the technology, in-depth research, and major complex studying among control variables, the West is still highly undeveloped; or, at least this is what one is lead to believe. However, there are many treatments, remission possibilities, and rehabilitation methods available. Among the many incurable diseases, Crohn’s disease has begun to resurface. This reappearance however, has been among children and teenagers not adults as witnessed in the past.

In the article entitled, “Pediatric Crohn’s Disease: Epidemiology, and Emerging Treatment Options”, Kansal and Smith explore Crohn’s disease and its affects globally on children ranging from 0-14 years of age. Crohn’s disease was first described as a clinical entity by Burrill B Crohn and colleagues in the USA in 1932 and has traditionally been regarded as a disease of the Western world. It is currently believed that Crohn’s disease occurs as part of interplay between environmental and immunological factors in a genetically susceptible host.  A rising incidence in both adults and children has been observed in recent years, with some studies suggesting a ten-fold to 20-fold increase in children over three decades. Crohn’s disease currently affects about 700,000 people in the USA and about a million in Europe. It’s a disease that affects the gastrointestinal tract (gut), which eventually causes bone degradation and/or abnormal growth among young children. Researchers have even reported it to relate to IBD (inflammatory bowel disease). It would make sense seeing as if the gut includes the small intestine which assists in digesting nutrients to be distributed throughout the body. Moreover, if the first initial site of absorption is interrupted, proper bowel movement, as well as building healthy bones in development suffer traumatically.

While the peak age of new diagnosis for Crohn’s disease overall is between the second and fourth decades, the average age in pediatric practice is about 11 years. A study from Scotland reported a doubling of the incidence of pediatric Crohn’s disease over the 15-year period to 1995, with an overall averaged standardized incidence rate of 2.5 cases per 100,000 populations for the period. Marked increases in pediatric diagnoses have also been confirmed in other parts of Europe, such as Sweden, Czechoslovakia, and the UK, while elsewhere, such as Canada and the USA, they appear to have plateaued after previously documented increases.

One of the most interesting conclusions is that genetic susceptibility for Crohn’s disease is defined as how the host interacts with its microbiota. The search for a microbial trigger for Crohn’s disease has been carried out in two ways, either a specific transmissible agent or a dysbiosis involving the gastrointestinal microbial milieu. With this, researchers have found many treatment options. Most treatment options have been reared toward inflammation. Traditionally, the Step-Up treatment option was used for adults, but history of the disease along with uprising epidemic, a  new method known as Top-down therapy is being administered to help with prevention of structural damage by achieving mucosal healing with this past use of immunosuppressants and biologicals. As mentioned, there is no cure for Crohn’s disease, but therapeutic interventions are designed to relieve symptoms, improve the quality of life, and avert-long-term complications.

Shavani Kansal, Anthony J. Smith (2014). Pediatric Crohn’s disease: epidemiology and emerging treatment options. Pediatric Health, Medicine and Therapeutic. University of Melborne.

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William R. Leonard is a leading anthropologist in the field of human nutrition. He was born in Jamestown, NY and received his PhD in biological anthropology from the University of Michigan at Ann Arbor in 1987. He is now an Abraham Harris Professor in the Department of Anthropology and the Chair of Anthropology at Northwestern University. He is also the Director of the Global Health Studies Program.

Siberia-2
Dr. William R. Leonard (left) with former student Josh Snodgrass, Univeristy of Oregon, conducting fieldwork in Siberia. (Photo provided by William Leonard)

Much of his research focuses on nutrition, energetics, and child growth in both modern and prehistoric human populations. He has traveled and studied in regions of South America, including Bolivia, Ecuador, and Peru, and also Siberia. In these regions, Leonard conducts research on population adaptation to their specific nutritional environment and how these adaptations affect their health, as well as contribute to chronic disease risks. Additionally, Leonard compiles information about human and primate ecology in order to examine the evolution of nutritional requirements in our hominid ancestors. This research leads to insight regarding the origins of obesity and metabolic diseases in contemporary human populations.

One recently published paper by Leonard, titled “The global diversity of eating patterns: Human nutritional health in comparative perspective” highlights Leonard’s work surrounding human nutrition, dietary trends, and the raising rates of obesity in the US. In the paper, he focuses on the different types of subsistence in the US versus less modern, more traditional societies. He notes that the energy intake between industrialized and non-industrialized societies is not different, but that the composition of nutrition includes higher levels of fats and carbohydrates in industrialized cultures. He also compares humans’ nutritional needs to primates, noting that the increase in brain size in higher-level primates such as humans has led to humans requiring higher quality foods than some of our close evolutionary relatives. As rates of obesity and chronic metabolic diseases continue to rise in the US and other industrialized societies, research such as Leonard’s studying the causes and origins of such nutritional deficiencies is of growing importance.

References:

Leonard, William R.

2014 The global diversity of eating patterns: Human nutritional health in comparative perspective. Physiology & Behavior 134:5-14.

Background information based on biosketch provided by Dr. William R. Leonard.

The human body is very complex, yet simple mechanism. The way in which cholesterol (fats), minerals, and vitamins contribute to the nutrients within the body range. The human body is made of millions of cells that are directed by DNA to make certain proteins, which then code for the insertion of amino acids (polypeptide chains). These amino acids then contribute to enzyme regulation and the production of hormones throughout the body. All of these components contribute to cell nutrients, the amino acids that our bodies are not capable of making must be consumed through foods. When the body does not consume the right amount of amino acid or vitamin supplement, it begins to become insufficient and incapable of ridding the body of toxic materials, as well producing a healthy immune system. In all, the way you eat, the amount of water consumed, and your ability to help the body rid unhealthy fats (toxins) by exercising and detoxification are the mechanisms for having a productive body.

Most Americans in the United States are considered to be obese. The body is made up of fat cells from the accumulation of cholesterol. Keep in mind, all fat isn’t bad fat. Yes, there are healthy fatty acids inside the body that contribute to the body’s overall energy consumption; hence; why one is able to exercise or simply keep the body in motion. Fatty acid cells are found in the muscles of cells and produced by lipoproteins. They are also referred to as adipose tissue. The accumulation of too many fatty acids cells contribute to obesity. Obesity is a condition that is considered to accompany an unhealthy lifestyle. It also slows the body’s circulation because not enough oxygen can pass through selectively permeable membranes. This in turn leads to blood clotting and obviously an accumulation of fatty tissue all over the body. Most people who are obese are consumers that cannot control their calorie intake. Calorie intake is the issue at hand in order to help produce a healthy lifestyle.

In the article I found entitled, “Calcium and Vitamin D for Obesity” researchers used a review of randomized control trials (RCT’S) to show if more calcium and vitamin D intake help contribute to weight loss. They used the trial with women only. Among these women, there hypothesis consisted of the idea that calcium intake during weight loss should result in greater fat loss. The fat percentage measured on the body is the total accumulation of fat in the body. The higher the percentage the higher the risk of heart disease. Also, weight loss was only considered in this trial in relation to BMI and fat percentage. Researchers were not simply intrigued by the number on the scale. They found that calcium and vitamin D support does not support calorie intake, but can suppress appetite. Researchers also reported higher calcium was much better than moderate calcium accelerating weight loss over time; though, differences in fat mass were not significant. On the other hand, vitamin D supplementation presented no effect on changes in body weight, waist-hip ratio, or percent fat mass. Overall, the idea that calcium and vitamin D contribute to weight loss was highly insignificant. I do believe the study may have been done broader and more biological aspects should have been taken into consideration. The study was only used with women, but the calcium or vitamin D present prior was not taken into consideration. These trials could have very well been witnessed on calcium deficient individuals, which then places the trial under high scrutiny. In other words, maybe this randomized trial should have been a conditioned group of women to measure such bodily contributions. Do you agree?

Delfos, Chan, Ghanbari M. Calcium and Vitamin D for Obesity: A Review of Randomized Trials. European Journal of Clinical Nutrition. Sept. 2011, Vol. 65. Issue 9 p. 994-1004.

(Ch.7 Blog entry- Human Nutrition)

In this week’s reading, climate change and adaption among humans was the issue at hand. We learned that human-occupied environments of today are extremely different from those of tropical forests beginnings as well, historical Neanderthals. Within environments, one’s body will either adapt to hot or cold conditions. The way in which the body adapts to these environments is known as thermoregulation in correspondence with homeostasis. They body reacts based solely on its environment. With this aspect, we can also expand this knowledge into broader realms of nutrition. In direct relation with body temperature, the contraction of muscles, and acclimatization, what is put into the body helps regulate certain temperatures. Ecologically speaking, agricultural production is also based on particular environmental conditions. Without the production of fruits, vegetables, and domesticated farm animals, the average human body cannot exist very long in strenuous environments of excess heat or extreme cold. This brings to my article entitled, “Public Health and Climate Change Adaptation at the Federal Level.”

In this piece, Jeremy J. Hess and Paul J. Schramm, identify on a federal level, agencies response to an executive order by President Obama among public health and climate change adaptation. They began by exploring what climate change is, and how it contributes to executive orders of public health. “Climate change is projected to cause many adverse health effects in the United States and abroad. The adverse health effects will result from a range of direct and indirect exposures that come from shifting ecosystems dynamics; worsening air quality, increasingly frequent and severe extreme heat events; shifts in precipitation, including more frequent and severe storms and floods; sea level rise; and ocean acidification.” The Department of Health and Human resources, which houses the CDC and other agencies, take part in a wide range of activities affected by climate change. It ranges from ensuring food safety to research formulating healthcare policy. Climate change and adaptation has become such a grave issue among the CDC that federal law has to be more incorporated for health disparities as well as a larger outlook on global warming. They begin with an assessment of recent and projected future climatic shift, considers how these shifts affect agency missions and operations, and then moves toward development of adaptation plan and a formalized institutional learning component.  CDC programs range from disaster preparedness to vector-borne and zoonotic disease programs to other programs addressing global health.

Each program seeks to identify populations most vulnerable to certain impacts, anticipate future trends, and assure systems are in place to detect and respond to emerging health threats, and take steps to assure that these health risks can be managed now and in the future. In my opinion, it seems like the government is actually taking human adaption to climate change into account globally. The interesting idea about this program projection and federal law efforts is the issue around disease. I’m fully aware that climate changes and other environmental factors contribute to disease, but with ongoing epidemic of Ebola, do you guys believe this executive order is reared more toward climate adaption, or public health, or both? This article was slightly misleading in my opinion, because of the executive order, the mention of disease, but not much information on direct contact with the human bodies throughout the U.S. and abroad. In other words, all these programs may sound intriguing, but when will they be implemented and to what extent?

J. Hess and J. Schramm. Public Health and Climate Change Adaptation at the Federal Level. American Journal of Public Health. march 2014, Vol 104, No. 3.