The Human Body In Health And Illness

In this keynote address, the author discusses perception of the body in the context of chronic illness compared with that of health. She describes changes that occur in illness with respect to time, space, morality, aesthetics, morality, technology, information, and interpersonal relationships using examples from her research, and explores the construction of illness and health identities.

The composition of the gut bacteria community is different between healthy individuals and colon cancer patients. Several butyrate-producing bacterial genera were under-represented in the stool of colorectal cancer patients compared to healthy individuals. Two of the Prevotella species identified were completely absent from the colon cancer samples analyzed. Prevotella was hypothesized to help maximize energy harvest from a plant-based diet. The higher levels of Prevotella in the healthy cohort may reflect differences in the intake of fiber and other plant compounds compared to the individuals with colon cancer. On the other hand, Acidaminobacter, Phascolarctobacterium, Citrobacter farmer, and Akkermansia muciniphila significantly over-represented in colorectal cancer (CRC) stool samples [104]. Akkermansia muciniphila are mucin-degrading species. These may influence the quantities of metabolites in the intestinal tract. Butyric acid was significantly lower in the faeces of colon cancer patients, since species of butyrate producing bacteria (such as Ruminococcus spp. and Pseudobutyrivibrio ruminis) were lower in stool samples from CRC patients compared to healthy controls. Butyrate is quite an important nutrient for normal colon cells, which was shown to reduce proliferation and induce apoptosis of human colon carcinomas cells alone or in combination with propionate. In another study, over 26 novel species assigned to the Helicobacter genus (more than 90% similarity) have been identified, only some of which have been directly associated with gastrointestinal cancers [105].

Global temperatures and the frequency and intensity of heatwaves will rise in the 21st century as a result of\\nclimate change. Extended periods of high day and nighttime temperatures create cumulative physiological\\nstress on the human body which exacerbates the top causes of death globally, including respiratory and\\ncardiovascular diseases, diabetes mellitus and renal disease. Heatwaves can acutely impact large populations\\nfor short periods of time, often trigger public health emergencies, and result in excess mortality, and\\ncascading socioeconomic impacts (e.g. lost work capacity and labor productivity). They can also cause loss\\nof health service delivery capacity, where power-shortages which often accompany heatwaves disrupt health\\nfacilities, transport, and water infrastructure.\\n

Heat also has important indirect health effects. Heat conditions can alter human behavior, the transmission\\nof diseases, health service delivery, air quality, and critical social infrastructure such as energy, transport,\\nand water. The scale and nature of the health impacts of heat depend on the timing, intensity and duration of\\na temperature event, the level of acclimatization, and the adaptability of the local population, infrastructure\\nand institutions to the prevailing climate. The precise threshold at which temperature represents a hazardous\\ncondition varies by region, other factors such as humidity and wind, local levels of human acclimatization\\nand preparedness for heat conditions.

Global temperatures and the frequency and intensity of heatwaves will rise in the 21st century as a result ofclimate change. Extended periods of high day and nighttime temperatures create cumulative physiologicalstress on the human body which exacerbates the top causes of death globally, including respiratory andcardiovascular diseases, diabetes mellitus and renal disease. Heatwaves can acutely impact large populationsfor short periods of time, often trigger public health emergencies, and result in excess mortality, andcascading socioeconomic impacts (e.g. lost work capacity and labor productivity). They can also cause lossof health service delivery capacity, where power-shortages which often accompany heatwaves disrupt healthfacilities, transport, and water infrastructure.

Heat also has important indirect health effects. Heat conditions can alter human behavior, the transmissionof diseases, health service delivery, air quality, and critical social infrastructure such as energy, transport,and water. The scale and nature of the health impacts of heat depend on the timing, intensity and duration ofa temperature event, the level of acclimatization, and the adaptability of the local population, infrastructureand institutions to the prevailing climate. The precise threshold at which temperature represents a hazardouscondition varies by region, other factors such as humidity and wind, local levels of human acclimatizationand preparedness for heat conditions.

Although the terms are often used interchangeably, poor mental health and mental illness are not the same. A person can experience poor mental health and not be diagnosed with a mental illness. Likewise, a person diagnosed with a mental illness can experience periods of physical, mental, and social well-being.

Mental and physical health are equally important components of overall health. For example, depression increases the risk for many types of physical health problems, particularly long-lasting conditions like diabetes, heart disease, and stroke. Similarly, the presence of chronic conditions can increase the risk for mental illness.2

Over long periods of time, individuals and communities can adapt to their local climates. When both warmer and colder temperatures go above or below those norms rapidly, scientific evidence shows that people become vulnerable to associated health effects related to those extremes. Studies suggest that climate change will greatly increase the severity and frequency of extreme temperature conditions, leading to increases in temperature-related illness and death1.

Environmental changes to the built environment can be effective protective measures for human health and against the effects of climate change. Green spaces and new technologies such as cool roofs can offer benefits in urban settings. Adaptation measures, such as increased access to air conditioning or cooling centers, can safeguard communities from the health impacts of extreme heat. Similarly, access to central heating can protect individuals from extreme cold. Additional examples include adding sound landscape design such as planting trees to shade public spaces and offer healthy exercise areas. These actions are also beneficial in that they help to reduce greenhouse gases.

Research and research translation are critical to further understanding the effects of temperature change on human health. In addition, research on early warning systems or heat wave response plans can help prepare individuals, workers, and communities. For example, temperature data are determined based on weather station records; however, actual exposure of individuals depends on their location. This can be influenced by urban heat islands, microclimates, and differences between indoor and outdoor temperatures. New technologies and research are addressing the need to better assess these differences in exposure and heat index.

Further research activities will continue to explore the following: the relationship between exposure to extreme high and low temperatures with human illness and mortality, along with the combination of other climate-stressors; an improved understanding of social determinants that contribute to vulnerability; and an assessment of future adaptive measures.

Microbes inhabit just about every part of the human body, living on the skin, in the gut, and up the nose. Sometimes they cause sickness, but most of the time, microorganisms live in harmony with their human hosts, providing vital functions essential for human survival. For the first time, a consortium of researchers organized by the National Institutes of Health has mapped the normal microbial makeup of healthy humans, producing numerous insights and even a few surprises.

Researchers found, for example, that nearly everyone routinely carries pathogens, microorganisms known to cause illnesses. In healthy individuals, however, pathogens cause no disease; they simply coexist with their host and the rest of the human microbiome, the collection of all microorganisms living in the human body. Researchers must now figure out why some pathogens turn deadly and under what conditions, likely revising current concepts of how microorganisms cause disease.

To define the normal human microbiome, HMP researchers sampled 242 healthy U.S. volunteers (129 male, 113 female), collecting tissues from 15 body sites in men and 18 body sites in women. Researchers collected up to three samples from each volunteer at sites such as the mouth, nose, skin (two behind each ear and each inner elbow), and lower intestine (stool), and three vaginal sites in women; each body site can be inhabited by organisms as different as those in the Amazon Rainforest and the Sahara Desert.

Where doctors had previously isolated only a few hundred bacterial species from the body, HMP researchers now calculate that more than 10,000 microbial species occupy the human ecosystem. Moreover, researchers calculate that they have identified between 81 and 99 percent of all microorganismal genera in healthy adults.

Researchers at the Washington University School of Medicine in St. Louis examined the nasal microbiome of children with unexplained fevers, a common problem in children under 3 years of age. Nasal samples from the feverish children contained up to five-fold more viral DNA than children without fever, and the viral DNA was from a wider range of species. Previous studies show that viruses have ideal temperature ranges in which to reprodu