Evidence mounts that gut bacteria can influence mood, prevent depression
, February 5, 2019
Of all the many ways the teeming ecosystem of microbes in a person’s gut and other tissues might affect health, its potential influences on the brain may be the most provocative. Now, a study of two large groups of Europeans has found several species of gut bacteria are missing in people with depression. The researchers can’t say whether the absence is a cause or an effect of the illness, but they showed that many gut bacteria could make substances that affect nerve cell function—and maybe mood.
“It’s the first real stab at tracking how” a microbe’s chemicals might affect mood in humans, says John Cryan, a neuroscientist at University College Cork in Ireland who has been one of the most vocal proponents of a microbiome-brain connection. The study “really pushes the field from where it’s been” with small studies of depressed people or animal experiments. Interventions based on the gut microbiome are now under investigation: The University of Basel in Switzerland, for example, is planning a trial of fecal transplants, which can restore or alter the gut microbiome, in depressed people.
Several studies in mice had indicated that gut microbes can affect behavior, and small studies of people suggested this microbial repertoire is altered in depression. To test the link in a larger group, Jeroen Raes, a microbiologist at the Catholic University of Leuven in Belgium, and his colleagues took a closer look at 1054 Belgians they had recruited to assess a “normal” microbiome. Some in the group—173 in total—had been diagnosed with depression or had done poorly on a quality of life survey, and the team compared their microbiomes with those other participants. Two kinds of microbes, Coprococcus and Dialister, were missing from the microbiomes of the depressed subjects, but not from those with a high quality of life. The finding held up when the researchers allowed for factors such as age, sex, or antidepressant use, all of which influence the microbiome, the team reports today in Nature Microbiology. They also found the depressed people had an increase in bacteria implicated in Crohn disease, suggesting inflammation may be at fault. [Continue reading…]
OxyContin maker explored expansion into ‘attractive’ anti-addiction market
, January 30, 2019
By David Armstrong, ProPublica, January 30, 2019
Not content with billions of dollars in profits from the potent painkiller OxyContin, its maker explored expanding into an “attractive market” fueled by the drug’s popularity — treatment of opioid addiction, according to previously secret passages in a court document filed by the state of Massachusetts.
In internal correspondence beginning in 2014, Purdue Pharma executives discussed how the sale of opioids and the treatment of opioid addiction are “naturally linked” and that the company should expand across “the pain and addiction spectrum,” according to redacted sections of the lawsuit by the Massachusetts attorney general. A member of the billionaire Sackler family, which founded and controls the privately held company, joined in those discussions and urged staff in an email to give “immediate attention” to this business opportunity, the complaint alleges.
ProPublica reviewed the scores of redacted paragraphs in Massachusetts’ 274-page civil complaint against Purdue, eight Sackler family members, company directors and current and former executives, which alleges that they created the opioid epidemic through illegal deceit. These passages remain blacked out at the company’s request after the rest of the complaint was made public on Jan. 15. A Massachusetts Superior Court judge on Monday ordered that the entire document be released, but the judge gave Purdue until Friday to seek a further stay of the ruling.
The sections of the complaint already made public contend that the Sacklers pushed for higher doses of OxyContin, guided efforts to mislead doctors and the public about the drug’s addictive capacity, and blamed misuse on patients.
Screen time has stunted the development of generations of children
, January 28, 2019
A study has linked high levels of screen time with delayed development in children, reigniting the row over the extent to which parents should limit how long their offspring spend with electronic devices.
Researchers in Canada say children who spent more time with screens at two years of age did worse on tests of development at age three than children who had spent little time with devices. A similar result was found when children’s screen time at three years old was compared with their development at five years.
“What is new in this study is that we are studying really young children, so aged 2-5, when brain development is really rapidly progressing and also child development is unfolding so rapidly,” Dr Sheri Madigan, first author of the study from the University of Calgary, told the Guardian. “We are getting at these lasting effects,” she added of the study.
The authors say parents should be cautious about how long children are allowed to spend with devices. [Continue reading…]
In hunter-gatherer societies, excellent metabolic health is sustained by very active ways of living and a wide range of diets
, January 18, 2019
Nutrition experts have long debated whether there is an optimal diet that humans evolved to eat. But a study published this month adds a twist. It found that there is likely no single natural diet that is best for human health.
The research, published in the journal Obesity Reviews, looked at the diets, habits and physical activity levels of hundreds of modern hunter-gatherer groups and small-scale societies, whose lifestyles are similar to those of ancient populations. They found that they all exhibit generally excellent metabolic health while consuming a wide range of diets.
Some get up to 80 percent of their calories from carbohydrates. Others eat mostly meat. But there were some broad strokes: Almost all of them eat a mix of meat, fish and plants, consuming foods that are generally packed with nutrients. In general, they eat a lot more fiber than the average American. Most of their carbohydrates come from vegetables and starchy plants with a low glycemic index, meaning they do not lead to rapid spikes in blood sugar. But it is also not uncommon for hunter-gatherers to eat sugar, which they consume primarily in the form of honey.
The findings suggest that there is no one “true” diet for humans, who “can be very healthy on a wide range of diets,” said the lead author of the study, Herman Pontzer, an associate professor of evolutionary anthropology at Duke University. “We know that because we see a wide range of diets in these very healthy populations.”
One thing hunter-gatherer populations have in common is a very high level of physical activity. Many walk between five and 10 miles a day. [Continue reading…]
New plant-focused diet would ‘transform’ planet’s future
, January 16, 2019
The first science-based diet that tackles both the poor food eaten by billions of people and averts global environmental catastrophe has been devised. It requires huge cuts in red meat-eating in western countries and radical changes across the world.
The “planetary health diet” was created by an international commission seeking to draw up guidelines that provide nutritious food to the world’s fast-growing population. At the same time, the diet addresses the major role of farming – especially livestock – in driving climate change, the destruction of wildlife and the pollution of rivers and oceans.
Globally, the diet requires red meat and sugar consumption to be cut by half, while vegetables, fruit, pulses and nuts must double. But in specific places the changes are stark. North Americans need to eat 84% less red meat but six times more beans and lentils. For Europeans, eating 77% less red meat and 15 times more nuts and seeds meets the guidelines.
The diet is a “win-win”, according to the scientists, as it would save at least 11 million people a year from deaths caused by unhealthy food, while preventing the collapse of the natural world that humanity depends upon. With 10 billion people expected to live on Earth by 2050, a continuation of today’s unsustainable diets would inevitably mean even greater health problems and severe global warming. [Continue reading…]
How Trump is poisoning America
, December 26, 2018
Had Donald J. Trump not won the presidency in 2016, millions of pounds of chlorpyrifos most likely would not have been applied to American crops over the past 21 months. It would not have sickened substantial numbers of farm workers, or risked what the Environmental Protection Agency’s own studies suggest could be continued long-term health problems for others exposed to the chemical at low levels.
Widespread concerns about chlorpyrifos led to its removal for nearly all residential uses in 2000. Environmental groups kept pushing, and two filed a petition with the E.P.A. in 2007 to ban it entirely on food crops. The E.P.A. eventually agreed in 2015, released its revised human health risk assessment in November 2016, and was ordered by a court to “take final action” by the end of March 2017.
Days after the assessment was released, Mr. Trump won the election. DowDuPont, the leading maker of the pesticide, donated $1 million to his inauguration. One of the early acts of the man Mr. Trump appointed to head the E.P.A., Scott Pruitt, was to quash the chlorpyrifos ban on March 29, 2017.
Since taking office, Mr. Trump has consistently sided with powerful economic constituencies in setting policy toward the air we breathe, the water we drink and the presence of chemicals in our communities.
In the process, he has frequently rejected or given short shrift to science, an instinct that has played out most visibly in his disdain for efforts to curb global warming but has also permeated federal policy in other ways. [Continue reading…]
Life expectancy declines in the U.S. but is increasing in most other developed nations
, November 29, 2018
Life expectancy in the United States declined again in 2017, the government said Thursday in a bleak series of reports that showed a nation still in the grip of escalating drug and suicide crises.
The data continued the longest sustained decline in expected life span at birth in a century, an appalling performance not seen in the United States since 1915 through 1918. That four-year period included World War I and a flu pandemic that killed 675,000 people in the United States and perhaps 50 million worldwide.
Public health and demographic experts reacted with alarm to the release of the Centers for Disease Control and Prevention’s annual statistics, which are considered a reliable barometer of a society’s health. In most developed nations, life expectancy has marched steadily upward for decades.
“I think this is a very dismal picture of health in the United States,” said Joshua M. Sharfstein, vice dean for public health practice and community engagement at the Johns Hopkins Bloomberg School of Public Health. “Life expectancy is improving in many places in the world. It shouldn’t be declining in the United States.” [Continue reading…]
Wildfire smoke is becoming a nationwide health threat
, November 23, 2018
NASA
Richard E. Peltier, University of Massachusetts Amherst
The impacts of recent forest fires in California reach well beyond the burned areas. Smoke from the Camp Fire created hazardous air quality conditions in San Francisco, more than 170 miles to the southwest – but it didn’t stop there. Cross-country winds carried it across the United States, creating hazy conditions in locations as far east as Philadelphia.
As an air pollution exposure scientist, I worry about the extreme levels of air pollution that rise from these fires and affect many people across great distances. They can create unhealthy conditions in far-flung locations where residents probably never think about wildfires. But since major wildfires are becoming increasingly common, I believe it is important for all Americans to know some basics about smoke hazards.
AP Photo/Eric Risberg
A complex and unpredictable threat
Forest fires do not discriminate about what they burn. Along with woody materials from forests and homes, they consume homes’ contents, which may contain plastics, petroleum products, chemicals and metals. This produces thick plumes of smoke that contains very large quantities of particles and gases. Many of these airborne chemicals are known to be quite toxic to humans.
Smoke plumes travel great distances, affecting communities hundreds of miles away. Winds tend to move from west to east across North America and carry these pollutants with them. Sometimes, depending on local weather conditions, the pollutants can be lifted up to high altitudes where wind speeds are faster and transported very quickly across the country. The pollutants can then descend back to the ground in locations far away from the fires, affecting everyone in their path.
The health of an ecosystem (including your home) depends on its biodiversity
, November 12, 2018
Rob Dunn invites us on a safari in pursuit of the wildlife teeming on our bodies and in every corner of our homes. For him, the creatures that sprawl in the human navel and under the bathroom shower head elicit the kind of wonder most of us would feel only on seeing the denizens of Tanzania’s Ngorongoro Crater or the Great Barrier Reef off Australia. Dunn is more than an informed and entertaining commentator, a David Attenborough of domestic biodiversity. He is a scientist whose research group at North Carolina State University in Raleigh made many of the discoveries described in his fascinating and illuminating book, Never Home Alone.
Dunn and his colleagues have used the concepts and techniques of community ecology to tease apart the functioning of a mostly ignored ecosystem: the human home. Their research enriches our understanding of ecosystem function, and — more grippingly — gives us insight into how our interactions with living things in the domestic habitat affect our health and well-being. The book is structured around sub-habitats in our homes — our bodies, rooms, water supply, pets and food. It considers an awesome range of organisms, from the rich fungal flora on bakers’ hands to the diversity of fly larvae in our drains.
We discover that warm, moist shower heads are ideal for the growth of biofilms containing trillions of bacteria, including Mycobacterium species that are harmful to human health. Dunn and his colleagues invited thousands of volunteers globally to send in samples from their bathrooms. The researchers are finding, for instance, that the more a water supply is treated with chemicals designed to kill microbes, the greater the abundance of pathogenic strains of mycobacteria. We also learn that the numbers of plant and butterfly species in our gardens are correlated with the robustness of the community of microbes on our skin; that some German cockroaches have evolved to perceive glucose as bitter, thus avoiding poisoned bait; and that dogs can give us both heartworm and a top-up of beneficial bacteria from their microbiomes.
The message of Never Home Alone is clear. The health of an ecosystem depends on its biodiversity: this is as true of our homes as of a mangrove swamp. Two factors, notes Dunn, are important. Simply by chance, a home containing more species is more likely to include organisms (especially microbes) that are vital in sparking our immune systems into life. And an ecosystem with niches fully occupied by diverse species is likely to be resilient and resistant to invasion by pests and pathogens. [Continue reading…]