Georgia Tech researchers found many types of bacteria, include E.coli, in the middle to upper regions of the troposphere. (Photo: USDA)

Scientists have discovered a considerable number of living microorganisms, including bacteria, in the middle to upper regions of the troposphere, the region of our atmosphere that’s about seven to 20 kilometers above the Earth’s surface.

Researchers from the Georgia Institute of Technology said their findings might help other scientists learn more about the role microorganisms play in forming ice that may impact weather and climate.

Health and medical experts studying the transmission of disease could also benefit by gaining new insight into long-distance transport of bacteria.

Conditions in the troposphere cannot support most other forms of life without the aid of special equipment. Temperatures there can drop to as low as -55° C and the air pressure and density are considerably lower than on earth.

Microorganisms, such as bacteria, are plentiful and can be found everywhere on the Earth and in the sea.

These hardy little forms of life not only survive but actually thrive in some of the harshest conditions known to man. They live within other forms of life, such as the human body; in the soil and the air surrounding us; in scalding hot springs; the great depths of the ocean; and inside rocks deep within the Earth’s crust.

A view outside the window of a DC-8 aircraft as air samples are gathered for a NASA study. Georgia Tech scientists found living microorganisms in the samples. (Photo: NASA)

The microorganisms  documented by Georgia Tech scientists were gathered from air samples recovered as part of NASA’s 2010 Genesis and Rapid Intensification Processes (GRIP) program, which studies low- and high-altitude air masses associated with tropical storms.

NASA gathered the air samples from aboard a DC-8 aircraft that flew over both land and ocean, including the Caribbean Sea and portions of the Atlantic Ocean during and after two major tropical hurricanes in 2010, Earl and Karl.

Attaching a special filter system developed by the Georgia Tech team to the aircraft’s outside air sampling probes, researchers were able to collect numerous particles, including the microorganisms.

Once the air samples were taken, the filters were removed from the aircraft and sent to researchers for examination.

Rather than resorting to conventional cell-culture techniques to make their analysis, the researchers instead used genomic techniques, including polymerase chain reaction (PCR) – a biochemical technology used in molecular biology that magnifies a piece of DNA, allowing scientists to generate millions of copies of the DNA sequence, as well as gene sequencing to spot and estimate the quantities of microorganisms contained within the air samples.

The researchers found more bacteria than fungi among the microorganisms.

“We did not expect to find so many microorganisms in the troposphere, which is considered a difficult environment for life,” said one of the study’s authors, Kostas Konstantinidis, an assistant professor at Georgia Tech. “There seems to be quite a diversity of species, but not all bacteria make it into the upper troposphere.”

Terry Lathem, a graduate student in Georgia Tech’s School of Earth and Atmospheric Sciences, aboard a NASA DC-8 aircraft while gathering samples of microorganisms in the atmosphere. (NASA)

The living bacterial cells found made up about 20 percent of the total particles detected within the size range of 0.25 to 1 microns in diameter.

Air samples taken over the ocean were found to contain mostly marine bacteria, while primarily terrestrial bacteria was found in samples taken above land.

The researchers also found that hurricanes had a major impact on the distribution and dynamics of microorganism populations.

Kostas Konstantinidis joins us for this weekend’s radio edition of Science World.  He’ll tell us how these findings could help advance research in climatology and medicine.

Check out the right column for scheduled air-times or listen now to the interview below.

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Children with a BMI in the 95th percentile are at risk for serious health problems, according to a new report. (Photo: Robert Lawton via Wikimedia Commons)

Obese children face many more immediate health issues and are at increased risk for medical, mental and developmental problems than was previously thought, according to a new report.

The study based on UCLA research found that obese children – those with a Body Mass Index (BMI) in the 95th percentile or above - are nearly two times more likely to have three or more physical or mental conditions than kids with a healthy weight.

Overweight children – those with a BMI in the 85th to 95th percentile – had about 1.3 times higher risk of developing adverse health conditions.

While most previous research focused on long-term health problems which could develop during adulthood, this study looked at the immediate consequences of childhood obesity.

The findings were based on information taken from a much wider and larger sample of participants than previous similar studies, according to researchers. Fifteen percent of the children studied were considered to be overweight and 16 percent were obese.

Compared to their normal-weight peers, obese children were more likely to be in poorer health, have more disabilities and more emotional and behavioral problems, such as having to repeat a grade, missing school and other educational difficulties.

Children classified as obese were also more likely to have conduct disorders, depression, learning disabilities, developmental delays as well as physical ailments such as bone, joint and muscle problems, allergies, headaches, asthma and ear infections.

“This study paints a comprehensive picture of childhood obesity, and we were surprised to see just how many conditions were associated with childhood obesity,” said lead author Dr. Neal Halfon, a UCLA professor who directs the Center for Healthier Children, Families and Communities. “The findings should serve as a wake-up call to physicians, parents and teachers, who should be better informed of the risk for other health conditions associated with childhood obesity so that they can target interventions that can result in better health outcomes.”

The World Health Organization (WHO) considers childhood obesity to be “one of the most serious public health challenges of the 21st century.” In 2010, the WHO found there were more than 42 million children under five worldwide who are overweight. Close to 35 million of those children live in developing countries.

Artist’s rendition of astronauts on Mars. (NASA)

Traveling into deep space could accelerate the onset of Alzheimer’s disease, an incurable form of dementia, according to a new report.

The NASA-funded study assessed how cosmic radiation would impact the astronauts throughout their trip in deep space. The effect of cosmic radiation on the human body has been a  concern for the US space agency as it plans manned missions into deep space, such as one to a distant asteroid in 2021, and another to Mars in 2035.

Earth’s magnetic field usually keeps us, and those in low Earth orbit, safe from the perils of cosmic radiation. However, beyond Earth’s protective magnetic fields, space travelers are exposed to a constant barrage of radiation.

With adequate warning, such as in the case of solar flares, steps can be taken to protect astronauts from dangerous forms of radiation. However, other forms of cosmic radiation, which occur without warning, cannot be blocked as effectively.

“Galactic cosmic radiation poses a significant threat to future astronauts,” said M. Kerry O’Banion,  a professor in the University of Rochester Medical Center (URMC) and senior author of the study. “The possibility that radiation exposure in space may give rise to health problems such as cancer has long been recognized. However, this study shows for the first time that exposure to radiation levels equivalent to a mission to Mars could produce cognitive problems and speed up changes in the brain that are associated with Alzheimer’s disease.”

Artist’s illustration of the shape and function of the Earth’s magnetic field that protects us from harmful cosmic radiation (NASA)

In the past,  scientists studied the impact of cosmic radiation on a living being’s cardiovascular and musculoskeletal systems, as well as potential risks of contracting various forms of cancer.But the new study,  published in  PLOS ONE, examined the possible effects of space radiation on neurodegeneration, a gradual loss of brain structure or function.

For this study, researchers wanted to find out what role, if any, cosmic radiation plays in accelerating the biological and cognitive indicators of Alzheimer’s disease, especially in those  predisposed to developing the illness.

They specifically wanted to learn more about the impact of radiation from high-mass, high-charged (HZE) particles, which come in many forms and travel through space with the force of exploding stars.

Instead of examining hydrogen protons, which are produced by solar flares, the researchers decided to study iron particles. They say HZE particles, such as iron, when combined with their high rate of speed, are able to go through solid objects, like a spacecraft’s walls and protective shielding.

“Because iron particles pack a bigger wallop, it is extremely difficult, from an engineering perspective, to effectively shield against them,” said O’Banion. “One would have to essentially wrap a spacecraft in a six-foot block of lead or concrete.”

Brain affected by Alzheimer’s Disease (left) vs normal brain (right) – (US Dept of Veterans Affairs)

The researchers exposed mice to various doses of radiation, including levels that would be similar to what astronauts would experience during deep space voyages.To evaluate the cognitive and biological impact of the radiation exposure, the mice were then put through a series of experiments in which they had to recall objects or specific locations. Researchers observed that the radiation- exposed mice were much more likely to fail these tests, suggesting neurological impairment, earlier than the symptoms would typically appear.

Along with symptoms of neurological damage, the researchers found that the mice’s brains also showed signs of vascular changes and had a greater than usual buildup of beta amyloid, the protein “plaque” that gathers in the brain and is one of the characteristics of Alzheimer’s Disease.

“These findings clearly suggest that exposure to radiation in space has the potential to accelerate the development of Alzheimer’s disease,” said O’Banion. “This is yet another factor that NASA, which is clearly concerned about the health risks to its astronauts, will need to take into account as it plans future missions.”

British scientists have found you can lose weight without dieting – by replacing high-fat foods with their low-fat counterparts.

Writing in the British Medical Journal,  researchers from the University of East Anglia found that people who switched out high-fat foods with low-fat substitutes lost about 1.6 kg over six months without any additional dieting.

They also found lowering fat in your diet provides additional health advantages, such as lowering blood pressure and bad cholesterol levels.

The researchers believe their findings could play a role in dietary recommendations to help in the worldwide battle against obesity. The WHO and other public health organizations say obesity is a major risk factor for high blood pressure, cardiovascular disease, diabetes, some cancers and musculoskeletal disorders, such as the highly disabling degenerative disease of the joints, osteoarthritis.

A display of high fat foods such as cheeses, chocolates, lunch meat, french fries, pastries, doughnuts, etc. (Photo: US National Cancer Institute)

Looking to update its guidelines on total fat intake, the WHO recently commissioned a study to evaluate the relationship between the amount of fat and fatty products  consumed in daily diets and various indicators of body fatness such as total weight, waist size and/or body mass index (BMI).

For their study, the researchers evaluated 33 trials in North America, Europe and New Zealand, involving 73,589 participants of various ages and states of health.

Researchers compared the waistline measurements and weight of participants who ate a reduced-fat diet with those whose diet included the usual amounts of fat for at least six months.

Along with the loss of 1.6 kg of bodyweight, they also found that the participants reduced their total BMI by 0.56kg/m² – kg per square meter -and cut their waist circumference by 0.5cm.

Nutritionists recommend foods with protein (eggs/lean meat), whole grains, and fruits (or vegetables) for a healthy breakfast (Photo: Kenji Ross via Flickr/Creative Commons)

Wondering if the weight reduction by those in the group that consumed few fats was due in part to the additional time, attention and support they received, compared to those in the normal fat intake group, researchers looked to studies where both groups were given equal time and attention and found that the weight reduction did not disappear suggesting that the weight loss was really due to lower fat intake.

“The effect isn’t dramatic, like going on a diet. The research specifically looked at people who were cutting down on fat, but didn’t aim to lose weight, so they were continuing to consume a normal amount of food,” said Dr. Lee Hooper, who led the research. “What surprised us was that they did lose weight, their BMI decreased and their waists became slimmer. On top of this, they kept their weight down over at least seven years. There isn’t a specific goal, the more fat you cut down, the more your weight falls.”

The amount of space junk floating around the Earth grows every year, and increasingly can pose risks to spacecraft orbiting the planet.

This computer generated graphic provided by NASA shows objects in Earth orbit that are currently being tracked. Space junk has made such a mess of Earth’s orbit that experts say we may need to finally think about cleaning it up. (AP)

In the United States, NASA’s Orbital Debris Program (ODP) at the Johnson Space Center in Texas, keeps an eye on the ever-expanding junkyard of space.

“We define orbital debris as any man-made object orbiting the Earth that is no longer serving a useful purpose,” says Gene Stansbery, project manager for the ODP. “That can be anything from very large rocket bodies and dead satellites that are no longer useful, all the way to very tiny particles that are eroded from the painted surfaces of spacecraft or rockets, the entire size range.”

In the weightless and friction-free environment of orbit, it’s not so much the size of all this junk floating in the Earth’s orbit, but also the speeds at which it travels, according to Stansbery.

“If you look at orbital velocities and the average collision velocity, you’re talking on the order of 11 kilometers a second,” he says. “So even a small paint fleck can damage a sensitive component for spacecraft.”

An example occurred during STS 7, when a window for the space shuttle had to be replaced for the first ever time after being damaged by a .2 millimeter paint fleck. If that level of damage can be caused by a particle that small, one can imagine the threat posed by larger orbiting refuse.

Given that space exploration has been an on-going venture since the 1950s, there’s a lot of old stuff circling the planet, and much of it can pose serious risks.

“The Department of Defense has a world-wide network that can track objects down to about 10 centimeters in size in low Earth orbit,” says Stansbery. “For those objects, there’s about 22,000 that they’re tracking. You go down to about one centimeter and larger, you’re talking about 500,000, and if you get smaller than that and you’re talking into the millions.”

Some of that stuff, especially in low-Earth orbit, will eventually fall back to the planet, much of it burning up on re-entry. However, for junk found at higher altitudes, around 1,000 kilometers or so, Stansbery says it could remain in orbit for decades, maybe even hundreds of years. For altitudes even higher than that, junk could remain for centuries…or longer.

A white arrow points to damage on a piece of a solar array from the Russian space station Mir. The array had been damaged by a miniscule piece of space junk. (AP)

Major collisions are rare, but they do happen. On Feb. 10, 2009, two large satellites, the Iridium 33 and the Kosmos 2251, collided at a speed of about 42,000 kilometers per hour. The collision spread about 1,000 pieces of debris capable of being tracked across the skies, where much of it remains.

In March of this year, one of those pieces came uncomfortably close to the International Space Station. So close, in fact, that as a precaution, the ISS’ six-member crew waited for a time in the Soyuz emergency exit capsule, just in case a collision occurred and they had to abandon ship.

More worrisome, says Stansbery, is that the crew only had 24 hours notice of the possible collision. “Unfortunately, that is too short a time to plan a re-avoidance maneuver for the space station,” he says.

The threat posed by space junk isn’t new; space scientists have been concerned about it since the 1970s. However, with more rockets taking off, more satellites in the sky, and more spacecraft – such as from China or private firms like SpaceX and Blue Origin – the skies are getting more crowded all the time.

This week on VOA’s “Science World” radio program, you can hear the complete interview with Gene Stansbury on space junk, as well as other features on the science behind children’s snack food choices, the lingering effects of the Gulf of Mexico oil spill on corral communities, and a new web-based computer program that helps doctors save lives. Take a look at the right hand column for scheduled times.

(Written by Doug Bernard,  Digital Frontiers Editor)

Influenza is unpleasant for many, and for some people, can be deadly. (Photo: NatalieJ via Flickr/Creative Commons)

Imagine that one day soon when you tune in to your favorite radio or TV station for the latest weather forecast, you’re given a flu forecast as well.

Adapting techniques used in modern weather prediction, scientists at Columbia University and the National Center for Atmospheric Research have come up with a way to produce localized forecasts of seasonal influenza outbreaks.

The researchers hope their new flu forecasting system, still in its initial phases, will serve both local and international health officials with highly detailed information, while also providing easier-to-understand versions for the general public. The researchers plan to get the system to an operational state within the next year or two.

Jeffrey Shaman, assistant professor of Environmental Health Sciences at Columbia University’s Mailman School of Public Health is the lead author of the study published in the Proceedings of the National Academy of Sciences. He says peak flu season can greatly vary from year to year, and from region to region.  For example, Atlanta, a Southern U.S. city might reach its peak flu season weeks ahead of Anchorage in the far northwest.

Students in Kazakhstan wear surgical masks to help prevent the spread of flu during the 2009 swine flu outbreak.  (Photo: Nikolay Olkhovoy via Wikmedia Commons)

The system will track flu outbreaks from week to week, location to location, showing the prevalence of flu in our own areas.

“I think what you can expect from it is weekly prognostications, weekly predictions, of how far in the future the peak of a flu outbreak is expected to be,” said Shaman.

Comparing his team’s flu forecasts to weathercasts we’re all used to, Shaman says the meteorological forecasts tell you, for example, that there’s an 80 percent chance of rain tomorrow, which prompts you to expect wet weather.

The flu forecast, on the other hand, would tell you that the peak of the flu season will be hitting your area within perhaps the next week or month reminding you to take any steps necessary to minimize the impact of the flu on you and your family.

The influenza forecast will also be able to provide data to health officials on the size and scope of the outbreak as well, allowing them to better plan a public health response.

Previous research conducted by Shaman and his colleagues found that U.S. wintertime flu epidemics were most likely to take place following a spell of very dry weather.

A microscopic image of the H1N1 (swine flu) influenza virus. In 2009, the World Health Organization declared this new strain to be a pandemic.

Using a computer model that incorporated this finding and feeding it web-based estimates of flu-related sickness in New York City from the winters of 2003-04 and 2008-09, Shaman and co-author Alicia Karspect of the the National Center for Atmospheric Research were able to produce weekly flu forecasts for those time periods that predicted the peak timing of the outbreak more than seven weeks ahead of the actual peak.

Shaman says that three ingredients are needed to do this kind of forecasting.

First, a mathematical model that describes the transmission of influenza within a specific population or community.

Next, real-time observations of what’s currently going on in the real world.  Shaman says data comes from web-based estimates of influenza-like illnesses, recorded by various hospitals and clinics that see or treat patients with symptoms consistent with the flu.

And finally, a statistical or data assimilation method similar to those used in weather forecasting, to pull in data from the observations into the model that generates the predictions.

Yes, a flu shot may sting a little bit but the CDC recommends a yearly flu vaccine as the first and most important step in protecting ourselves against flu viruses. (Photo: US Navy)

Variations made to the incoming data stream, as conditions change, keep the model updated and on track to better reflect real-world conditions allowing for much more accurate forecasts.

Shaman and his research colleagues plan to test their system in other localities across the US by using up-to-date data.

“There is no guarantee that just because the method works in New York, it will work in Miami,” Shaman said.

Jeffrey Shaman joins us this weekend on the radio edition of “Science World.”  Tune in to the radio program (see right column for scheduled times) or check out the interview below.

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(Image: Copyright American Heart Association)

Looking old on the outside might be a clue to what’s going on inside your body, according to new research from the American Heart Association.

The study finds that people who have three or four physical signs of aging —a receding hairline, baldness, a crease in the earlobe, or  yellow fatty deposits around the eyelid— also have a 57 percent increased risk for heart attack and a 39 percent increased risk for heart disease.

“The visible signs of aging reflect physiologic or biological age, not chronological age, and are independent of chronological age,” said Anne Tybjærg-Hansen, M.D., the study’s senior author and professor of clinical biochemistry at the University of Copenhagen in Denmark.

Tybjærg-Hansen and her colleagues studied nearly 11,000 test participants as part of the Copenhagen City Heart Study. They were 40 or older, and almost half were women.

In the study group, 7,537 of them had frontoparietal baldness, which is a receding hairline at the temples; 3,938 were bald at the top of their heads; 3,405 had an earlobe crease; and 678  had yellow fatty deposits around the eye.

Over a 35-year period, researchers followed the subjects and found that 3,401 of them developed heart disease and 1,708  experienced a heart attack.

Among the four signs of aging cited in the study include a crease in the earlobe (Photo: National Human Genome Research Institute)

Looking at the test subjects both individually and as a group,  researchers found that the identified signs of aging were  predictors of heart attack and heart disease, or both, without considering traditional risk factors, such as high-blood pressure, cholesterol, smoking, physical inactivity or obesity.

In particular, the study found that fatty deposits around the eye were the strongest single predictor of both heart attack and heart disease.

Each additional sign of aging, among both men and women,  suggested an increased  risk of heart attack and heart disease. So if an individual initially had a receding hairline but later developed an ear crease, the risk of heart problems increased as well.

The study found that those in their seventies, and those who had those multiple aging signs, had the highest risk of coronary problems.

To gather data for the study, various healthcare workers, including nurses and laboratory technicians, examined the test subjects, recording the amount of gray hair they had; how wrinkled their faces were; the type and level of baldness; and whether or not they had an earlobe crease or eyelid deposits.

These findings, according to the researchers, suggest that doctors and other healthcare workers should look for these external signs of heart problems, while also considering traditional risks.

“Checking these visible aging signs should be a routine part of every doctor’s physical examination,” Tybjærg-Hansen said.

Eating breakfast may help keep you from getting fat and making poor food choices (Photo: Angela de Março via Flickr/Creative Commons)

Skipping breakfast sets the brain up to make poor food choices later in the day, according to a new study.

Scientists from the MRC Clinical Science Centre at London’s Imperial College, compared the brain scans and eating patterns of people both after eating breakfast and when they were fasting.

They found that those who avoid breakfast may overeat throughout the rest of the day, often choosing high-calorie or junk food over healthier selections.

The researchers studied the magnetic resonance images (MRIs) of 21 volunteer test subjects who didn’t eat anything before coming in for their tests.  On one those visits, the volunteers were first given a 750-calorie breakfast before the researchers ran the MRI scans.

On another visit to the research center, the test subjects weren’t fed any breakfast, but were always served lunch after each scanning session.

“Through both the participants’ MRI results and observations of how much they ate at lunch, we found ample evidence that fasting made people hungrier, and increased the appeal of high-calorie foods and the amount people ate,” said Dr. Tony Goldstone, who led the study.

Researchers believe the brain’s orbitofrontal cortex (highlighted in this MRI image) might play a key role in influencing food choices. (MRI Image: Paul Wicks via Wikimedia Commons)

While examining the MRIs of volunteers who hadn’t eaten breakfast, the scientists found a variation in the pattern of activity in the orbitofrontal cortex, that’s the area of the brain located right above the eyes that can affect decisions concerning the appeal and reward value of food.

When participants who were fasting or didn’t eat any breakfast were shown pictures of high-calorie food,  the MRIs showed that that portion of the brain was “activated,” a reaction less strong when they had eaten breakfast.

After studying and comparing the MRI scans over a period of time, the researchers were able to use the brain scans to predict which of their test subjects would be the mostly likely to respond strongly to high-calorie foods.

To Goldstone and his colleagues, these findings suggest  the orbitofrontal cortex may play a key role in influencing people in making their food choices.

They also say their research complements previous studies that show fasting may not be the best way to lose weight, since doing so tends to create a “bias” in the brain that makes us seek a high-calorie food reward.

Nutritionists recommend foods with protein (eggs/lean meat), whole grains, and fruits or vegetables, for a healthy breakfast (Photo: Kenji Ross via Flickr/Creative Commons)

Eating a healthy breakfast doesn’t necessarily mean sitting down to a formal meal or even eating traditional breakfast foods like cereals or eggs.

You can mix up the food items you want to eat for breakfast and that could also include eating some of those tasty leftovers from the previous night’s dinner.

Here are some tips and suggestions on healthy breakfast choices from the Academy of Nutrition and Dietetics:

• Include some lean protein, such as eggs, cheese, deli meat, peanut butter, Canadian bacon or yogurt
• Pair that lean protein with a whole-grain carbohydrate food, such as a whole-grain cereal, bread, waffles, pancakes or oatmeal
• Be sure to include fruits and vegetables to your breakfast  Top off yogurt with some fruit or chop up some veggies to add to your omelet
• To save time, nutritionists suggest prepping breakfast the night before

Many factors influence a woman’s self-perception of physical attractiveness. New research shows that genetics may also play a role in how some women gauge their body image. (Photo: Christine Tremoulet via Flickr/Creative Commons)

While cultural and societal factors have long been thought to influence how women see themselves in the mirror, a new study in Michigan has revealed that genetics may also play a role in making some women more vulnerable to the pressure of being thin.

Many people today, especially women, have taken the modern axiom, “Thin is In“ to heart.  So much so that a number of those pushing themselves to lose weight in order to become thin have developed serious problems such as the potentially deadly eating disorder, Anorexia Nervosa.

Women are constantly reminded by the media that it’s best to be thin.  From size-zero models to airbrushed film stars, thinness is portrayed as equaling beauty across Western culture. While both genders are subject to this pressure, it tends to fall harder on women for a variety of reasons. That skinny ideal can cause women to have a poor body image in the way they see themselves and imagine how they look.

Michigan State University researcher Jessica Suisman led a study that focused on the possible psychological impact of women who actually believe this perceived ideal of thinness, something the researchers called “thin-ideal internalization.”

Ms. Suisman and her colleagues gathered more than 300 female twins, from 12 to 22 years of age, from the Michigan State University Twin Registry, to participate in the study.  The researchers first made a measurement of the women’s “thin idealization” — or just how much their study subjects wanted to look like the thin women who are often shown on TV and in magazines.

In western cultures women are constantly reminded by the media that it’s best to be thin. (Photo: Helga Weber via Flickr/Creative Commons)

Once these measurements were made, the researchers then compared the genetics of identical twins, who share 100 percent of their genes, with those of fraternal twins who share 50 percent.

The researchers, examining the results of these measurements found that identical twins have a close to identical level of thin idealization than their fraternal twin cohorts.  To Suisman and her colleagues this suggests that genetics play a significant role in pressuring women to believe that they need to be thin (“thin idealization”).

As they continued their analysis of the data, the researchers found that the heritability of thin idealization is 43 percent, which they believe means that nearly half of the reasons women differed in their idealization of thinness can be explained by variations in their genetic makeup.

But Suisman pointed out that their research did not find a specific gene that makes a woman think, ‘I want to be thin.’  “That wouldn’t make any sense because we haven’t always had these thin models as our ideals,” said Suisman.   “We aren’t sure exactly what these same genes would have done many years ago or even in a different culture in the world where thinness isn’t seen as the equivalent for beauty,” she adds.

Suisman’s research team also looked at what environmental influences, such as friends, family, society and/or culture, were most important in determining how women felt about their bodies and how much they wanted to look like the ‘media ideal.’

A study led by Jessica Suisman, from Michigan State University, suggests that, for some women, genes may influence the pressure to be thin. (Photo: Michigan State University)

“And what we actually found was that environmental influences that were really specific to each individual woman, rather than the general environment was more important,” said Suisman.  In other words, individual experiences such as having friends and peers who are focused on thinness, or being involved in a sport that’s also focused on thinness, were more important and played more of a role in pressuring women to be thin than general societal and cultural influences.

“The take-home message,” Suisman said, “is that the broad cultural risk factors that we thought were most influential in the development of thin-ideal internalization are not as important as genetic risk and environmental risk factors that are specific and unique to each twin.”

Jessica Suisman joins us this weekend on the radio edition of Science World.  She tells us more about her research and findings and how genetics could play a role in pushing women to focus on being thin.

Check out the right column for scheduled air-times or listen now to the interview below.

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