New technology could capture ammonia from liquid manure

Posted by Biomechanism 

Process utilizes filtering material designed for synthetic blood vessels.

Though it may not sound very glamorous, a new method of extracting ammonium from liquid animal manure could be exciting news for both confined animal operations and environmental groups, according to a Texas AgriLife Extension Service engineer.

Dr. Saqib Mukhtar, (foreground) Texas AgriLife Extension Service engineer, and Dr. MD Borhan, Texas AgriLife Research scientist, pose with a lab-bench scale test of a process that can extract 50 percent of the dissolved ammonium in liquid manure in 20 days. Photo: Robert Burns.

The method uses gas-permeable membrane technology that tests have shown could remove 50 percent of the dissolved ammonium in liquid manure in 20 days. The removed ammonium is “not scrubbed but captured,” said Dr. Saqib Mukhtar, AgriLife Extension engineer and interim associate department head of the Texas A&M University department of biological and agricultural engineering.

By captured, Mukhtar means, the ammonium is concentrated as ammonia sulfate compound, which as commercial fertilizer could potentially offset the cost of the removal process.

Though still in the lab-bench test stage, the technology shows great promise to solve a long-standing, expensive well-documented problem that confined-animal feeding operations such as dairies and feedlots face daily, Mukhtar said.

“Excessive ammonia emissions from animal feeding operations are considered a source of odor and environmental pollution,” Mukhtar said. “Once emitted, ammonia may contribute to formation of fine airborne particulates in the presence of certain acidic compounds in the atmosphere.”

Also, ammonia emissions from improperly managed manure systems may contaminate groundwater and cause excessive vegetative growth in lakes and reservoirs, he said.

“And it may even be a constituent of nitrous oxide, a potent greenhouse gas,” he said.

There are other methods of mitigating ammonia emissions from manure storage and treatment facilities, including acidic solution-sprayed scrubbers and bio-filters, and chemicals such as acidified clays and sodium hydrogen sulfate, Mukhtar said.

“Several of these methods have been promising, but high costs, lack of ‘staying power’ of chemicals and other additives, lack of ammonia recovery for beneficial uses, and the complex operation and management of some of the technologies have restricted their extensive use in animal agriculture,” he said.

In comparison, the membrane technology Mukhtar and his associates have been testing is relatively simple.

Gas-permeable tubing is submersed in a tank of liquid manure. A very dilute solution of sulfuric acid is pumped through the tubing, which has a porosity of only 2 microns. To put this in perspective, a typical human hair is 70 microns in diameter.

The method takes advantage of a property of dissolved gases described by Fick’s first law of diffusion. A high concentration of a dissolved gas, such as ammonia, will migrate to regions of lower concentration. As the concentration of ammonium is high in the liquid manure and low to zero in the permeable tubing, the ammonium is drawn into the tubing and out of the liquid manure.

Also, the migration is enhanced by ammonium being a base and chemically attracted to the acid in the tubing.

The name of the tubular membrane they used is “expanded polytetrafluoroethylene, which is usually abbreviated ePTFE,” Mukhtar said.

The product has several uses including blood filtration and synthetic blood vessel and even dental floss, he said, and once was prohibitively expensive. But with the expiration of several patents for this material and its uses, the cost has dropped dramatically, allowing its use for other applications.

Mukhtar said the next step is to scale up from the small bench model to a large tank, perhaps 100 gallons, he said. The team also wants to experiment with how little tubing can be used, and how dilute the acid solution can be, while still capturing about 50 percent of the ammonium within a reasonable amount of time.

They are also looking ahead to learn how to economically scale up the process for use on the farm.

“Obviously, we can’t use a ‘gazillion’ feet of tubing in a large manure lagoon,” Mukhtar said. “Potentially, what we could do is divert some of the flushed manure in a much smaller basin and apply membrane technology to extract ammonia from it.”

The manure from which the ammonia has been extracted would then be transported back into the large lagoon, he said

“By doing this repeatedly, we could concentrate ammonia as a relatively high pH solution of ammonium sulfate,” Mukhtar said.

The team headed by Mukhtar includes Amir Samani Majd, a doctorate candidate; Dr. MD Borhan, assistant research scientist; and John Beseda, student technician, all based in College Station. The team presented the results of their study in a paper at the American Society of Agricultural and Biological Engineers annual international meeting at Louisville in mid-August. The title of the paper was “An Investigation of Ammonia Extraction from Liquid Manure Using a Gas-Permeable Membrane.”

“Remember, we are capturing ammonia with this process,” Mukhtar said. “Not just scrubbing it as other processes do. We might be able to return part or all of its cost of the process as ammonium sulfate, an expensive fertilizer.”

Women Face Transportation Hurdles

 BY DONNA BARNE, EXTERNAL RELATIONS, THE WORLD BANK

Studies in Morocco, West Bank and Yemen Aim to Inform Public Transport Strategies

Gender Action Plan transport studies of 2008 and 2010 in Casablanca, Morocco, the West Bank, rural and urban Yemen, revealed that women face higher costs and bigger hurdles to getting around than men. The studies concluded that the transportation systems do not adequately serve the needs of female populations in these areas, but predictable public transport schedules, sidewalks and street lighting, increased numbers of bus stops and pedestrian crossings, could all improve their mobility and safety while traveling.

Women tend to use public transportation more than men, but limited transportation routes or schedules restrict the ways in which they live their lives. They also spend 15-20 percent more than men on transportation in the West Bank and urban Yemen, according to the studies, because they are more constrained than their male counterparts by cultural and societal factors as well as by family duties. Safety and hygiene concern them too, especially when they travel with children.

Women have multiple roles. They work outside the home, fulfill wide-ranging family needs outside of typical commuting hours and require access to education and health services for themselves and their children. This means that they have “a different way of moving,” says Lamis Aljounaidi, a former junior professional associate at the World Bank, who managed the studies in the West Bank and Yemen.

“We want people to be better aware that there is a gender dimension to transport,” says World Bank Transport Economist, Jean-Charles Crochet, who led the studies in Yemen and Casablanca.

DIFFICULT COMMUTES IN MOROCCO

The studies indicate that transportation barriers affect women’s ability to earn an income.

“Women living in the rapidly growing Casablanca suburbs, for instance, face difficult commutes to textile factories where there is demand for labor,” says Crochet, adding, “The study shows that women want to participate in the workforce, but the transport system, which does not perform well, does not help…It’s difficult to go from certain parts of town to the industrial zones. Women find they cannot reconcile the needs of family life with the needs of their employment.”

"Women find they cannot reconcile the needs of family life with the needs of their employment.”
Jean-Charles Crochet

Nevertheless, women’s growing participation in labor markets has had drastic consequences on the demand for urban transport in Morocco. In response, Morocco is now eyeing new strategies for urban transport throughout the country.

In early 2011, the World Bank approved a Euro 100 million development policy loan in support of this effort.

FEW WOMEN WORKERS IN THE WEST BANK

In the West Bank, women make up less than 15 percent of the workforce, despite a female literacy rate of 90 percent—the highest in the Middle East and North Africa.

“One of the main reasons for women’s low levels of employment is accessibility—the lack of smooth access from their home to the workplace and back,” says Ibrahim Dajani, a senior operations officer who led the West Bank study.

A working woman here typically faces a long and uncertain commute that may involve switching between different modes of transportation or multiple vehicles—mainly buses or shared taxis that rarely take people directly to their destinations. In addition, checkpoints may cause further delays that are unacceptable to working mothers.

“Private taxis are too expensive for most people, and private transportation (i.e., cars) is usually used by a male member of the family,” says Aljounaidi. While 21 percent of men use privately-owned means of transport (cars, etc.), only 8 percent of women do so. The others (92 percent of the women surveyed and 79 percent of the men) walk or use public transportation.

“When resources are limited, men tend to take them and it has always been like that,” says Aljounaidi. “Women tend to take public transportation and walk more than men, and that is why women experience more problems, because public transportation is difficult and sidewalks are very bad. This impacts women more than men because they have less access to private transportation.”

Dajani says that transportation on the West Bank could become more efficient and acceptable to women. As government resources are limited, however, the effort would likely involve consolidating the many privately-owned bus companies in order to make transport and access to the finance required to replace the aging bus fleet more viable.

A separate but complementary World Bank-financed study proposed a pilot project in which bus companies in the northern West Bank merge, adopt integrated fares and allow transfers to lower costs for operators and customers.

“The pilot would involve studying each route and seeing who the clients are, along with their destinations, in order to restructure the routes to benefit not only women and men but also vulnerable groups,” says Dajani.

TRANSPORTATION AND EDUCATION IN YEMEN

In Yemen, less forms of transportation are available. Those that are, are more costly for women than men. In rural Yemen, social pressure “greatly constrains” women’s mobility. Transportationcosts women 50 percent more than men because they must ride in covered vehicles—and many cannot afford to pay. The result is that women tend to walk.

The study notes that roads have, however, brought schools and health care facilities to villages, or to more accessible locations, giving women better access to basic education and mother and child care.

"It is impossible for women to get an education if there is not a secure means of transport, because the family will just not let her go." Jean-Charles Crochet

About 55 percent of women had at least a basic education in communities where a road had existed for 15 years or more, versus some 32 percent in places without a road. About 40 percent of women had access to mother and child care facilities in areas with an old road, and 18 percent in places where a road had been recently built, but only 5 percent had such services if there was no road at all.

In Yemen’s capital city, Sana’a, infrastructure has lowered the cost of access to education, services, jobs and economic opportunities for women in established areas of the city. But safer, more secure urban transportation could enhance these opportunities further, says Crochet.

“What is important in Yemen is access to education—whether it is education for young women, or continuing education for women who may already have a job. It is impossible for women to get an education if there is not a secure means of transport, because the family will just not let her go. So urban transport has a tremendous impact on the ability of young women to improve themselves.”

Click here to download the full 2011 Gender Action Plan booklet

Polar dinosaur tracks found in Australia

Rachel's 9th Birthday Wish

In Rachel's words... On June 12th 2011, I'm turning 9. I found out that millions of people don't live to see their 5th birthday. And why? Because they didn't have access to clean, safe water so I'm celebrating my birthday like never before. I'm asking from everyone I know to donate to my campaign instead of gifts for my birthday. Every penny of the money raised will go directly to fund freshwater projects in developing nations. Even better, every dollar is "proved" when the projects are complete, and photos and GPS coordinates are posted using Google Earth. My goal is to raise $300 by my birthday, June 12, 2011. Please consider helping me. Thank you so much!!! >>>>> Posted July 25, 2011 by Rachel's Mom, Samantha I am in awe of the overwhelming love to take my daughters dream and make it a reality. In the face of unexplainable pain you have provided undeniable hope. Thank you for your generosity!  I know Rachel is smiling! http://mycharitywater.org/rachels9thbirthday

When you can recite a poem but not remember who asked you to learn it a few days earlier

 Neuroscience 

Memory is not a single process but is made up of several sub-processes relying on different areas of the brain. Episodic memory, the ability to remember specific events such as what you did yesterday, is known to be vulnerable to brain damage involving the hippocampus. The question is, what happens when damage to the hippocampus occurs very early in life? In a case study published in the September 2011 issue of Elsevier's Cortex, clinical neuropsychologists have reported that a child can develop normally despite severe damage to the hippocampus resulting from lack of oxygen in the first days of life. This supports the theory that the different aspects of memory rely on distinct areas of the brain.

Dr. Claire Bindschaedler and Dr. Claire Peter-Favre from the Neuropsychology Unit of Lausanne's University Hospital in Switzerland, together with their colleagues Prof. Philippe Maeder, Dr. Thérèse Hirsbrunner and Prof. Stephanie Clarke, investigated the case of a patient known as VJ, one of the few cases of developmental amnesia reported in the scientific literature. Repeated neuropsychological testing showed that VJ cannot remember being read a story or shown a picture half an hour earlier, or at least remembers little of it. At the same time however, VJ does do well on tests of general knowledge, also called semantic memory. In fact, when tested regularly over his childhood and teenage years, VJ was found to develop at the same rate as other children in areas of general knowledge and general intelligence.

Analysing MRI scans of VJ's brain, Dr. Philippe Maeder found very severe atrophy (wasting away of brain tissue) in the hippocampi, while the adjacent area of the brain, known as the perirhinal cortex, was relatively spared from damage. This latter area is hypothesised to be important for the acquisition of semantic memory. These findings lend support to the idea that episodic memory (but not semantic memory) depends on the hippocampus.

More information: The article is "Growing up with bilateral hippocampal atrophy: From childhood to teenage" by Claire Bindschaedler, Claire Peter-Favre, Philippe Maeder, Thérèse Hirsbrunner, Stephanie Clarke, and appears in Cortex, Volume 47, Issue 8 (September 2011)

Provided by Elsevier

"When you can recite a poem but not remember who asked you to learn it a few days earlier." August 11th, 2011.http://medicalxpress.com/news/2011-08-recite-poem-days-earlier.html

Posted by
Robert Karl Stonjek

GABA link to impulsive males

 Psychology & Psychiatry 
(Medical Xpress) -- The reason why some men are more impulsive, act aggressively, drink and take drugs could lie in the fact that they have lower levels of a naturally occurring substance in a specific part of their brain, University research has uncovered.

Using the latest brain imaging techniques scientists from Cardiff University’s Brain Imaging Research Imaging Center (CUBRIC) and University College London have identified a new link between impulsiveness and levels of GABA, a very common neurotransmitter, in a very specific part of the brain.

"Advances in brain imaging techniques mean we are able to investigate different and specific areas of the human brain and see how they regulate people’s behavior," according to Dr. Frederic Boy, School of Psychology, who led the research published in the journal Biological Psychiatry and funded by the Wellcome Trust.

"What is clear is that the way people behave results from a complex interaction between a number of genetic, social and environmental factors, what we’ve found is that one of the reasons why some men act impulsively may be related to the lower concentration of GABA in a specific part of men’s brains."

The scientists studied male undergraduate students with no history of psychiatric disorders or substance dependence.

They underwent a specialized magnetic resonance spectroscopy brain scan, an imaging technique that allows measuring the amount of GABA in small regions of the brain followed by a questionnaire which helped assess different aspects of impulsivity, an important component of self-control.

The team found that individuals with more prefrontal GABA had lower scores in one aspect of impulsivity called the "feeling of urgency", the tendency to act rashly in response to distress or other strong emotions and urges. Inversely individuals with lower GABA tended to have higher urgency ratings.

The link with GABA was specific to the dorsolateral prefrontal cortex, a region previously implicated in higher cognitive functions.

The team hope that their research helps show a specific relationship between the brain’s basic physiology, such as GABA-mediated signalling, and complex behavioral regulation can be uncovered.

Dr. Boy adds: "The ability to regulate our behaviour in response to a constantly changing physical and social world is key to adapted life.

"Failure in this finely tuned mechanism is particularly important in most psychiatric disorders, where impulsivity is the second most common symptom. We hope this research will lead to further studies and help bridge the gap between recent genetic studies and imaging studies of psychiatric disorders. "

Provided by Cardiff University

"GABA link to impulsive males." August 11th, 2011. http://medicalxpress.com/news/2011-08-gaba-link-impulsive-males.html

Posted by
Robert Karl Stonjek

Regulation of attention and concentration in brain unravelled

 Neuroscience 

(Medical Xpress) -- The prefrontal cortex of the brain is involved in memory processes and the ability to concentrate attentively. Neuroscientists from VU University Amsterdam have shown how and where this occurs in the prefrontal cortex. The research provides insight into how the brain regulates attention and concentration and gives new clues for the treatment of memory problems in elderly people. The results will be published tomorrow in the scientific journal Science.

Memory and concentration will decline during aging in over one in three people. That is partly because the amount of the neurotransmitter acetylcholine in the brain decreases. Acetylcholine transmits signals from one nerve cell to another. Memory and concentration may improve by stimulating the receptor in the brain that captures and recognizes acetylcholine. This improves the transmission of signals in the brain, resulting in improved concentration and memory. The researchers demonstrated in their study that a specific component of the acetylcholine receptor is essential for optimal concentration. In addition, they showed in which part of the brain this process occurs.

The researchers performed their study with mice in which that specific component of the receptor had been ‘turned off’. A special attention test showed that these mice were not able to concentrate. Then the researchers used a virus to replace the receptor component in a specific part of the prefrontal cortex, the prelimbic cortex. The result was that the mice were now able to concentrate well. Replacement of the receptor component in a different part of the brain, the anterior cingulate cortex, did not recover concentration. The researchers have therefore shown which component of the receptor is responsible for attention and concentration, and also where in the brain this occurs.

The results of the study provide an important contribution to our understanding of how attention and concentration in the brain is controlled at the molecular level. This knowledge also gives new clues for further research that may lead to improved treatment of problems with concentration and memory that occur during aging.

More information: The article Nicotinic acetylcholine receptor β2-subunits in the medial prefrontal cortex control attention will be published on August 12 in Science. 

Provided by VU University Amsterdam

"Regulation of attention and concentration in brain unravelled." August 11th, 2011.http://medicalxpress.com/news/2011-08-attention-brain-unravelled.html

Posted by
Robert Karl Stonjek

Brain electrical activity spurs insulation of brain's wiring

(Medical Xpress) -- Researchers at the National Institutes of Health have discovered in mice a molecular trigger that initiates myelination, the process by which brain cell networks are reinforced with an insulating material called myelin that speeds their ability to transmit messages.

The myelination process is an essential part of brain development. Myelin formation is necessary for brain cells to communicate and it may contribute to development of skills and learning.

The researchers showed that an electrical signal passing through a brain cell (neuron) results in the brain cell releasing the molecule glutamate. Glutamate, in turn, triggers another type of brain cell, called an oligodendrocyte, to form a point of contact with the neuron. Signals transmitted through this contact point stimulate the oligodendrocyte to make myelin protein and begin the process of myelination. In this process, the oligodendrocyte wraps myelin around axons— the long, cable-like projections that extend from each neuron. The myelination process is analogous to wrapping electrical tape around bare wires.

Electrical signals transmitted from one neuron to the next are a basic form of communication in the brain. The myelin layers that oligodendrocytes wrap around neurons boost these signals so that they travel 50 times faster than before.

The study was conducted by Hiroaki Wake, Philip R. Lee, and R. Douglas Fields of the Nervous System Development and Plasticity Section of the NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD). Their findings appear online in Science Express.

“Insulation begins to form on axons in the late stages of fetal development, but the process continues through childhood, adolescence, and into early adulthood,” said Dr. Fields, the study’s senior author. “For example, infants cannot hold up their heads or walk until the appropriate motor axons become myelinated, and the frontal lobes of the brain, responsible for judgment and higher-level complex reasoning, are not fully myelinated until the early twenties.”

Understanding how oligodendrocytes generate and help repair myelin could provide insight into how only the appropriate axons in the brain become insulated during development as people acquire skills, with the eventual goal of helping them do so more efficiently, Dr. Fields explained. Similarly, understanding the myelination process could lead to insights into disorders like multiple sclerosis, in which myelin is either damaged or destroyed. Moreover, understanding myelination may allow researchers to speed myelination— and repair— of axons recovering from injury.

Throughout the brain, oligodendrocytes and neurons exist side by side. The researchers placed mouse nerve cells and myelin-making oligodendrocytes together in a dish and stimulated the nerve cells with electrical pulses. After three weeks, they found that the nerve cells were wrapped in a myelin covering.

In a separate culture of neurons and oligodendrocytes, the researchers blocked the release of the molecule glutamate, a neurotransmitter. Neurotransmitters make it possible for signals to pass between cells. When glutamate release was blocked, very little myelin coating formed. Further experiments showed that after the electrical pulses and the release of glutamate, nerve cells and the neighboring oligodendrocytes began sending chemical signals back and forth. Then the oligodendrocytes started to make the protein used to form the myelin sheath. Specifically, receptors on the cell membrane of oligodendrocytes detect glutamate released by the axon, and this triggers the formation of what the researchers termed specialized adhesive signaling junctions—points of contact between oligodendrocytes and axons that enable signals to be passed between the cells. Then the oligodentrocytes began depositing myelin on electrically active axons, but not on axons that were not electrically active.

“This shows that axons that are transmitting electrical signals will become preferentially insulated by myelin,” Dr. Fields said.

In a previous study, Dr. Fields and his coauthors found that electrical activity in neurons stimulates other cells, called astrocytes, that also are involved in the myelination process.

Provided by National Institutes of Health

"Brain electrical activity spurs insulation of brain's wiring." August 11th, 2011. http://medicalxpress.com/news/2011-08-brain-electrical-spurs-insulation-wiring.html

Comment:Myelin is a living cell, the Schwann cell, in the peripheral nervous system (one Schwann cell between each pair of nodes of Ranvier).

Posted by
Robert Karl Stonjek

Satya Sai death mystery deepens - Tv9

TV9 - Sathya Sai devotees demands for release Sai's death secret

TV9 - What happened to Sathya Sai in Hospital ?

TV9 - Mystery behind Satya Sai treatment

Shirdi sai baba slokas by haridasu2

Shirdi sai baba slokas by haridasu2

Red meat linked to increased risk of type 2 diabetes

Posted by Biomechanism 

A new study by Harvard School of Public Health (HSPH) researchers finds a strong association between the consumption of red meat—particularly when the meat is processed—and an increased risk of type 2 diabetes. The study also shows that replacing red meat with healthier proteins, such as low-fat dairy, nuts, or whole grains, can significantly lower the risk.

Based on these results, the researchers advise that consumption of processed red meat—like hot dogs, bacon, sausage, and deli meats, which generally have high levels of sodium and nitrites—should be minimized and unprocessed red meat should be reduced. If possible, they add, red meat should be replaced with healthier choices, such as nuts, whole grains, low-fat dairy products, fish, or beans.

The study, led by An Pan, research fellow in the HSPH Department of Nutrition, will be published online in the American Journal of Clinical Nutritionon August 10, 2011 and will appear in the October print edition.

Pan, senior author Frank Hu, professor of nutrition and epidemiology at HSPH, and colleagues analyzed questionnaire responses from 37,083 men followed for 20 years in the Health Professionals Follow-Up Study; 79,570 women followed for 28 years in the Nurses’ Health Study I; and 87,504 women followed for 14 years in the Nurses’ Health Study II.

They also conducted an updated meta-analysis, combining data from their new study with data from existing studies that included a total of 442,101 participants, 28,228 of whom developed type 2 diabetes during the study. After adjusting for age, body mass index (BMI), and other lifestyle and dietary risk factors, the researchers found that a daily 100-gram serving of unprocessed red meat (about the size of a deck of cards) was associated with a 19% increased risk of type 2 diabetes. They also found that one daily serving of half that quantity of processed meat—50 grams (for example, one hot dog or sausage or two slices of bacon)—was associated with a 51% increased risk.

“Clearly, the results from this study have huge public health implications given the rising type 2 diabetes epidemic and increasing consumption of red meats worldwide,” said Hu. “The good news is that such troubling risk factors can be offset by swapping red meat for a healthier protein.”

The researchers found that, for an individual who eats one daily serving of red meat, substituting one serving of nuts per day was associated with a 21% lower risk of type 2 diabetes; substituting low-fat dairy, a 17% lower risk; and substituting whole grains, a 23% lower risk.

Based on these results, the researchers advise that consumption of processed red meat—like hot dogs, bacon, sausage, and deli meats, which generally have high levels of sodium and nitrites—should be minimized and unprocessed red meat should be reduced. If possible, they add, red meat should be replaced with healthier choices, such as nuts, whole grains, low-fat dairy products, fish, or beans.

Worldwide, diabetes has reached epidemic levels, affecting nearly 350 million adults. In the U.S. alone, more than 11% of adults over age 20—25.6 million people—have the disease, according to the Centers for Disease Control and Prevention. Most have type 2 diabetes, which is primarily linked to obesity, physical inactivity, and an unhealthy diet.

Previous studies have indicated that eating processed red meats increases the risk of developing type 2 diabetes. Risks from unprocessed meats have been less clear. For instance, in 2010, HSPH researchers found no clear evidence of an association between eating unprocessed meats and increased risk for either coronary heart disease or type 2 diabetes, but that study was based on smaller samples than the current study, and the researchers recommended further study of unprocessed meats. Another HSPH study in 2010 linked eating red meat with an increased risk of heart disease—which is strongly linked to diabetes—but did not distinguish between processed and unprocessed red meats.

This new study—the largest of its kind in terms of sample size and follow-up years—finds that both unprocessed and processed meats pose a type 2 diabetes risk, thus helping to clarify the issue. In addition, this study is among the first to estimate the risk reduction associated with substituting healthier protein choices for red meat.

“Our study clearly shows that eating both unprocessed and processed red meat—particularly processed—is associated with an increased risk of type 2 diabetes,” said Pan. He noted that the 2010 U.S. dietary guidelines continue to lump red meat together with fish, poultry, eggs, nuts, seeds, beans, and soy products in the “protein foods” group. But since red meat appears to have significant negative health effects—increased risk of diabetes, cardiovascular disease, and even total mortality, as suggested by several recent studies—Pan suggested the guidelines should distinguish red meat from healthier protein sources and promote the latter instead.

________________

Support for the study was provided by the National Institutes of Health’s National Institute of Diabetes and Digestive and Kidney Diseases and the National Heart, Lung, and Blood Institute.

“Red Meat Consumption and Risk of Type 2 Diabetes: 3 Cohorts of U.S. Adults and an Updated Meta-Analysis,” An Pan, Qi Sun, Adam M. Bernstein, Matthias B. Schulze, JoAnn E. Manson, Walter C. Willett, and Frank B. Hu, American Journal of Clinical Nutrition, online August 10, 2011.