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Will a diet that's good for the planet also help you live longer? Here's the evidence

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Will a diet that's good for the planet also help you live longer? Here's the evidence

A new study finds that the more people followed environmentally sustainable diets that emphasized nutrients from plants, the lower their risk of death from cancer, heart disease, Alzheimer’s disease and a variety of other causes.

(J.M. Hirsch / Associated Press)

Every time you scoop up a spoonful of overnight oats or sink your teeth into a cheeseburger, you’re eating for two — for the sake of your own health and the health of the planet.

Researchers estimate that about 30% of greenhouse gas emissions, 40% of land use and 70% of freshwater use is tied to the production of food. The strain will only grow as Earth’s population climbs toward the 10 billion mark by 2050.

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Will it be possible to provide all those people with a nutritious diet in a way that’s environmentally sustainable?

That question prompted an international group of scientists to create a “planetary health diet” that’s heavy on plants — including vegetables, fruits, whole grains, nuts, legumes and unsaturated oils from sources like olives and canola — along with with modest amounts of dairy, poultry, fish and other foods derived from animals. It also allows for a little bit of red meat, refined grains and sugar. (You can even have a burger about once a week.)

If the whole world were to embrace a diet like this — along with adopting better agricultural practices and reducing food waste — greenhouse gas emissions would be cut roughly in half, the scientists calculated when they introduced their eating plan in 2019. They also projected that the number of premature deaths around the world would fall by up to 24%.

“That amounts to about 11 million deaths per year” that wouldn’t happen, said Dr. Walter Willett, a co-chair of the group known as the EAT-Lancet Commission.

Now Willett and his colleagues at Harvard University have checked their work against real-world data.

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The Harvard team created a Planetary Health Diet Index, which quantifies the degree to which a person’s diet adheres to the goals put forth by the commission. There are 15 food groups, and people were scored on a 5-point or 10-point scale for each one. The maximum possible score was 140, which would signify perfect alignment with the ideal eating plan.

The researchers assigned PDHI scores to more than 200,000 people enrolled in the Nurses’ Health Study, the Nurses’ Health Study II and the Health Professionals Follow-up Study. All of the participants gave detailed information about their diets when they joined the studies in the 1970s and 80s, and they updated that information at least once every four years for more than two decades.

The women in the two Nurses’ Health Studies improved their diets over time: The average index score for participants in NHS1 increased from 75.7 in 1986 to 84.5 in 2010, while the average for women in NHS2 jumped from 70.4 in 1990 to 85.9 in 2015. However, the average score for men in HPFS held steady at around 78.

By the time the tracking periods came to an end in 2019, 54,536 people in the three studies had died.

The researchers hypothesized that the higher a person’s PDHI score, the lower their risk of being among the deceased. And after accounting for demographic factors such as age, race and neighborhood income as well as health issues like a family history of cardiovascular disease or cancer, that’s exactly what they found.

“We did see a very strong, very clear inverse relationship,” said Willett, a professor of epidemiology and nutrition at the Harvard T.H. Chan School of Public Health. “Right down the line, everything we looked at was lower for people who adhered most closely to the planetary health diet.”

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Compared to the 20% of people with the lowest index scores, the 20% with the highest scores were 23% less likely to die for any reason during the study period. They were also 14% less likely to die of cardiovascular disease, 10% less likely to die of cancer, 47% less likely to die of a respiratory ailment, 28% less likely to die of a neurodegenerative disease such as Alzheimer’s, and 22% less likely to die of an infectious disease.

Among all the men and women, eating more whole grains, fruit, poultry, nuts, soy and unsaturated fats were each associated with a lower risk of death. On the other hand, eating more starchy vegetables like potatoes, red or processed meats, eggs, saturated fats, added sugar or sugar from fruit juices were each associated with a higher risk of death.

Willett and his collaborators also consulted a database that tallied the environmental impacts of various foods to see whether healthier diets were better for the planet. Compared to the diets of people with the lowest PDHI scores, the diets of those with the highest scores required 21% less fertilizer, 51% less cropland and 13% less water and produced 29% fewer greenhouse gas emissions.

Willett said he was “surprised by the strength of some of these findings,” adding that the relationship goes both ways. For instance, when fewer acres are farmed, there’s less particulate matter in the air, and when fewer animals are raised in close quarters, the risk of antibiotic resistance declines.

“There are lots of very important indirect effects on health that are mediated by a better environment,” he said.

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The results were published Monday in the American Journal of Clinical Nutrition.

This isn’t the first study to link planetary health diets to a reduced risk of premature death — researchers have seen the connection in the United Kingdom and in Sweden. But the new work is the first to apply a more precise diet index to a large sample of Americans and use it to assess their risk of death.

That is an “important” advance, said Zach Conrad, a professor at William & Mary who specializes in nutritional epidemiology and food systems.

However, he said more work is needed to show that planetary health diets are as good for the Earth as they are for Earthlings.

“It has yet to be demonstrated that healthy diets are also more environmentally sustainable,” said Conrad, who was not involved in the new study. “It is important that we move away from inferring a link between diet quality and sustainability, and instead move toward measuring it.”

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Antibiotics wreak havoc on the gut. Can we kill the bad bugs and spare the good ones?

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Antibiotics wreak havoc on the gut. Can we kill the bad bugs and spare the good ones?

Inside every human is a thriving zoo of bacteria, fungi, viruses and other microscopic organisms collectively known as the microbiome. Trillions of microbes live in the digestive tract alone, a menagerie estimated to contain more than 1,000 species.

This ecosystem of tiny stuff affects our health in ways science is only beginning to understand, facilitating digestion, metabolism, the immune response and more. But when serious infection sets in, the most powerful antibiotics take a merciless approach, wiping out colonies of beneficial bacteria in the digestive tract and often prompting secondary health problems.

“Increasingly, researchers are recognizing the benefits of protecting the human gut microbiome, particularly because its integrity and diversity is linked to metabolic influences on mental health and physical health conditions,” said Dr. Oladele A. Ogunseitan, a professor of population health and disease prevention at UC Irvine.

Drug-resistant bugs are evolving faster than new medicines are being developed, rendering the current arsenal of medicines increasingly ineffective. But the more we understand about the microbiome, the clearer it is that we need antibiotics that are discerning in their targets.

With that goal in mind, a chemistry team at the University of Illinois Urbana-Champaign is experimenting with a compound that attempts to address both problems. The antibiotic, lolamicin, both successfully vanquished several drug-resistant pathogens in mice while sparing the animals’ microbiome. The results were published in the journal Nature.

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“Only recently has it been recognized that killing these [beneficial] bacteria is having many deleterious effects on patients,” said Paul J. Hergenrother, a chemistry professor at the University of Illinois Urbana-Champaign who co-led the study. “We have been interested for some time in finding antibiotics that would be effective without killing the good bacteria.”

The team set out to create an antibiotic that would both preserve the gut microbiome while targeting gram-negative bacteria, a particularly hardy category of superbugs. Encased in both an inner and outer membrane that antibiotics struggle to cross, gram-negative bacteria are resistant to most currently available therapies. They are responsible for the majority of the estimated 35,000 deaths in the U.S. each year from drug-resistant infections, according to the U.S. Centers for Disease Control and Prevention.

Worldwide, antimicrobial resistance kills an estimated 1.27 million people directly every year and contributes to the deaths of millions more.

Not all gram-negative bugs make us sick. Bacteria populations in the average human gut are roughly split between gram-negative and gram-positive types, said Kristen Munoz, a former doctoral student at the University of Illinois who co-led the study.

Broad spectrum antibiotics can’t tell which bugs to spare, she said. As a result, anything strong enough to treat a bad infection “is going to wipe out a good amount of your gut microbiome,” she said, even though they “aren’t doing anything wrong.”

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The team focused its search for a new drug on compounds that suppress the Lol system, which shuttles lipoproteins between the inner and outer membranes in gram-negative bacteria.

The Lol system’s genetic code looks different in harmful bacteria than it does in beneficial ones, which suggested to researchers that medicines that targeted the Lol system would be able to distinguish good bugs from bad ones.

The team designed multiple versions of these Lol-inhibiting compounds. When tested against 130 drug-resistant strains of Escherichia coli, Klebsiella pneumoniae and Enterobacter cloacae, one in particular proved especially potent.

They tested this antibiotic, which they named lolamicin, on mice that had been infected with drug-resistant strains of septicemia or pneumonia. All of the mice with septicemia survived after receiving lolamicin, as did 70% of the mice with pneumonia.

To measure the effect on gut bacteria, the researchers gave healthy mice either lolamicin, a placebo or one of two common antibiotics, amoxicillin and clindamycin. After collecting baseline stool samples, they sampled the animals’ poop seven, 10 and 31 days after treatment.

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Mice treated with amoxicillin or clindamycin had lower beneficial bacteria counts and less diversity of gut bacteria. In contrast, the guts of lolamicin-treated mice appeared largely the same.

“It was exciting to see that lolamicin did not really cause any changes in the microbiome, whereas the other clinically used antibiotics did,” Munoz said.

A disrupted microbiome can have immediate consequences for people battling infection. When beneficial microbes are decimated, dangerous bugs have fewer competitors and secondary infections can take hold.

Clostridium difficile is a notorious opportunistic pathogen, so the researchers did an experiment where they exposed mice treated with lolamicin, amoxicillin or clindamycin to C. difficile. The mice who took standard antibiotics were soon crawling with C. difficile. The lolamicin mice showed little to no infection.

The lab hopes to one day take lolamicin or a version of it to clinical trials, Hergenrother said. (Munoz received her doctorate last year and now works as a scientific analyst in Los Angeles.) Yet these are still early days for the drug. While the concept of a discerning antibiotic is a welcome development, it must clear significant barriers before it could make a difference for patients.

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“Distinguishing a quote-unquote ‘bad bug’ from a quote-unquote ‘good bug’ is not always as straightforward as it may seem,” said Dr. Sean Spencer, a Stanford University gastroenterologist and physician scientist who was not involved with the research.

Some beneficial bugs in the gut bear a striking genetic resemblance to harmful pathogens, he said. Others are benign in some contexts and dangerous in others: “In a critically ill individual, a good bug can do bad things.”

Years can pass between a new antibiotic’s proof of concept and its entry to the market, and the vast majority never make it to the end of that pipeline. It’s also not clear how easily or how quickly bacteria will develop resistance, which is perhaps the most formidable obstacle that lolamicin or any new antibiotic faces.

“One of the biggest problems is that bacteria are so smart. You can tackle one particular protein system or protein target in bacteria, but they will quickly find a resistance mechanism,” Munoz said. “They just have so many inherent mechanisms to overcome antibiotics.”

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Doctors and dentists at L.A. County-run hospitals will get bonuses under tentative deal

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Doctors and dentists at L.A. County-run hospitals will get bonuses under tentative deal

Unionized doctors and dentists who work at hospitals and other health facilities run by Los Angeles County will get cost-of-living increases and bonuses under new agreements with the county, reached after more than two years of bargaining and threats of a strike.

The tentative agreements with a pair of bargaining units represented by the Union of American Physicians and Dentists are expected to be voted on this month by the Los Angeles County Board of Supervisors.

Members of the Union of American Physicians and Dentists had geared up to go on strike in December, complaining that inadequate benefits had hampered recruitment and retention and driven up vacancy rates for crucial positions in county facilities, including for psychiatrists in its jails.

Much of the dispute centered on the “Megaflex” benefits package that L.A. County provides to more than 14,000 employees including managerial and administrative staff, most of whom are not unionized. That package gives workers an additional 14.5% to 19% over their base pay to buy benefits and allows them to keep any unspent portion as income, according to county officials.

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UAPD pushed for its members to get those benefits. The Department of Health Services countered that they already had an “extensive benefits package” — the same one in place for more than 35,000 other county workers — and that giving all of them a more costly package would prevent the county from concentrating its incentives on the hardest-to-recruit workers.

The two sides also sparred over the costs of expanding Megaflex: At one point, UAPD officials estimated the added costs at roughly $20 million a year based on current wages, but county officials had pegged the expected expense at more than $86 million a year, with costs rising with any salary increase.

The planned strike in December was put on hold after the county and the union agreed to seek opinions from outside experts about the implications of expanding Megaflex.

In late April, the UAPD announced that its negotiating teams had reached tentative agreements with the county, which were ratified by union members by the end of May.

Under the deal, the workers would get cost-of-living increases that match those received by other county employees, with additional hikes for some positions ranging from 2.75% to 19.25%, according to the county chief executive office. Starting wages were also increased for some medical specialties such as neurology.

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In addition, the county agreed to bolster benefits “no later than January 1, 2026,” according to the chief executive office. The added benefits include a 401(k) plan, as well as short-term disability benefits for physicians, who had complained that doctors were not getting enough paid time off to recover from childbirth.

The existing set of benefits put female physicians planning to become pregnant “at a disadvantage compared to private hospitals in the area,” said Dr. Michelle Armacost, a physician specializing in neurology at one of the county facilities, in a statement released by the union. “We demanded equitable benefits, and we were willing to strike for them. The county heard us, and we prevailed.”

Beyond those increases, county workers who are not covered by Megaflex will get an annual bonus of $14,000 on top of their base salary, according to the chief executive office. Union officials also said the deal features a “physician loyalty bonus for residents who choose to remain with the county after residency.”

“These new agreements set competitive wages and attractive benefits that we hope will allow us to fill critical vacancies at our county-run hospitals and other facilities and retain the talented healthcare workers already providing essential services to our county residents,” the chief executive office said in a statement.

County officials did not immediately provide an estimate of the costs of the new contract with the unionized doctors.

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Benefits have long been a bone of contention for county physicians. Doctors employed by L.A. County were cut off from Megaflex benefits more than two decades ago, a few years after they had voted to unionize.

At the time, county officials said such benefits were available only to nonunionized employees. “The doctors, they knew full well what they were getting into,” then-Supervisor Don Knabe said in 2001.

Labor officials decried it as a move to break the fledgling union, calculating the value of the benefits package at $19,000 or more to some senior doctors at the time. State lawmakers then banned the county from removing workers from a benefits plan because they unionized, making the law retroactive to before the L.A. County move. The UAPD also sued the county, eventually securing over $10 million in settlement.

The union later negotiated a new agreement with the county that grandfathered in existing workers on Megaflex, but put new hires on a different plan, the county chief executive office said. As of December, only a small number of UAPD members — fewer than 200 — had Megaflex benefits, according to the county.

In a report last year to county supervisors, Dr. Christina R. Ghaly, director of the Department of Health Services, said that over the years, “steady increases in salary were negotiated while factoring in that this group does not receive Megaflex benefits.”

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UAPD President Dr. Stuart Bussey rejected the idea that they had “bargained Megaflex away” at a public rally last year. In the past, “recruitment wasn’t as bad as it is now,” and a state law limiting pension benefits for government employees wasn’t in effect, Bussey told the crowd. “Times have changed.”

In a recent statement to union members, Bussey said that UAPD members had “refused to settle until we secured a collective bargaining agreement that prioritizes patient care with competitive pay and benefits.”

“Your determination and patience paid off, and we look forward to collaborating with the county to fill vacant positions.”

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Ed Stone, JPL director and top scientist on Voyager mission, dies at 88

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Ed Stone, JPL director and top scientist on Voyager mission, dies at 88

Ed Stone, the scientist who guided NASA’s breakthrough Voyager mission to the outer planets for 50 years and led the Jet Propulsion Laboratory when it landed its first rover on Mars, died Tuesday. He was 88.

A physicist who got in on the ground floor of space exploration, Stone played a leading role in NASA missions to Mars, Jupiter, Saturn, Uranus and Neptune. The discoveries made under his watch revolutionized scientists’ understanding of the solar system and fueled humanity’s ambition to explore distant worlds.

Carolyn Porco, who worked on imaging on JPL’s Voyager and Cassini missions, called Stone “a thoroughly lovely man” who was “as close to perfect as a project scientist could ever be.”

“When two science teams were in contention over some spacecraft resource, and Ed had to decide between the two, even the guy who lost went away thinking, ‘Well, if this is what Ed has decided, then it must be the right answer,’” Porco said by email Tuesday. “I feel blessed to have known Ed. And like many people today, I’m very sad to know he’s gone.”

Stone was a 36-year-old Caltech physics professor in 1972 when he was asked to serve as chief scientist for an audacious plan to send a pair of spacecraft to explore the solar system’s four giant planets for the first time.

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It was the opportunity of a lifetime, but he wasn’t sure he wanted the gig.

“I hesitated because I was a fairly young professor at that point. I still had a lot of research I wanted to do,” he recalled 40 year later.

He took it anyway, and from the mission’s first encounter with Jupiter in 1979 to its final flyby of Neptune in 1989, Stone became the scientific face of the Voyager mission. He guided the science agenda and helped the public make sense of revolutionary images and data not just from Jupiter, Saturn, Uranus and Neptune, but from many of their fascinating moons.

Stone and his more than 200 science collaborators were the first to discover lightning on Jupiter and volcanoes on its moon Io. They spotted six never-before-seen moons around Saturn and found evidence of the largest ocean in the solar system on Jupiter’s moon Europa, as well as geysers on Neptune’s moon Triton.

“It seemed like everywhere we looked, as we encountered those planets and their moons, we were surprised,” Stone told the Los Angeles Times in 2011. “We were finding things we never imagined, gaining a clearer understanding of the environment Earth was part of. I can close my eyes and still remember every part of it.”

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The Voyager 1 spacecraft became the first manmade object to reach interstellar space in 2012, and Voyager 2 followed suit in 2018.

Stone, pictured with a model of the Voyager spacecraft, said the discovery of volcanoes on Io was a highlight of the mission.

(NASA)

The twin probes continue to send weekly communications to Earth from interstellar space. Stone retired in 2022 on the mission’s 50th anniversary.

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“A part of Ed lives on in the two Voyager spacecraft. The fingerprints of his dedication and keen leadership are woven into the Voyager mission,” said Linda Spilker, who joined the mission in 1977 and succeeded him as project scientist.

The Voyager mission was Stone’s crowning achievement, but hardly his only one.

He was a principal investigator on nine NASA missions and a co-investigator on five others, including several satellites designed to study cosmic rays, the solar wind and the Earth’s magnetic field.

He became director of the Jet Propulsion Laboratory in La Cañada Flintridge in 1991, a role he held for a decade.

It was an era of cost-cutting at NASA, but Stone still managed to launch Galileo’s five-year mission to Jupiter and send the Cassini spacecraft to Saturn. He was also at the agency’s helm when Mars Pathfinder delivered the Sojourner rover to the Red Planet. It marked the first time that humans had put a robotic rover on the surface of another planet.

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Throughout his tenure at JPL, Stone continued to work and teach at Caltech, even teaching freshman physics during some of Voyager’s long cruise times between planets.

He also served as chairman of the board of the California Assn. for Research in Astronomy, which is responsible for building and operating the W.M. Keck Observatory and its two 10-meter telescopes on Mauna Kea, Hawaii.

Edward Carroll Stone Jr. was born in Iowa on Jan. 23, 1936, and grew up in Burlington, where his father ran a small construction business and his mother kept the company books.

The eldest of two brothers, Stone was attracted to science from a young age. Under his father’s watchful eye, he learned how to take apart and reassemble all varieties of technology, from radios to cars.

“I was always interested in learning about why something is this way and not that way,” Stone told an interviewer in 2018. “I wanted to understand and measure and observe.”

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After studying physics at Burlington Junior College, he received his master’s and doctorate at the University of Chicago. Shortly after he began his graduate studies, news broke in 1957 that the former Soviet Union had launched Sputnik, the world’s first artificial satellite.

“Just like that, because of the Cold War and our need to match Sputnik, a whole new realm absolutely opened up,” he said.

Stone built a device for measuring the intensity of solar energetic particles above the atmosphere that hitched a ride to space aboard an Air Force satellite in 1961. Unfortunately the spacecraft’s transmitter didn’t work, so only a very limited quantity of data was returned to Earth. However, it was still enough to indicate that the intensity of the particles was lower than expected.

Despite the transmitter glitch, Stone said the project was thrilling. “We were taking the first steps in a whole new area of research and exploration,” he said. “We were right at the beginning.”

He joined the faculty at Caltech in 1964 and created more space experiments, this time for NASA.

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Stone’s particular area of interest was cosmic rays — high-speed atomic nuclei that can originate from explosive events on the sun or from violent events beyond the solar system.

One of his cosmic-ray experiments was included among the 11 major Voyager experiments.

Ed Stone gestures in front of a reddish background

Ed Stone in 2011, about a year before Voyager 1 entered interstellar space.

(Al Seib / Los Angeles Times)

Colleagues praised Stone for his leadership of the Voyager science team.

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“He was a great hero, a giant among men,” said Porco, adding that Stone was known to treat everyone — from top scientists to graduate students — with respect.

Voyager team scientist Thomas Donahue put it this way: “Over the years, Ed Stone has proved to be remarkably adept at keeping a bunch of prima donnas on track.”

Stone was elected to the National Academy of Sciences in 1984 and received the National Medal of Science from President George H.W. Bush in 1991 in recognition of his leadership of the Voyager mission. He won the Shaw Prize in Astronomy in 2019, an honor that comes with a $1.2-million award. In 2012 his hometown of Burlington, Iowa, named its new middle school after him.

“This is truly an honor because it comes from the community where my exploration journey began,” Stone told a local newspaper.

Decades after Voyager’s launch he was asked to select his favorite moment from the mission. He chose the discovery of volcanoes on Jupiter’s moon Io.

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“Finding a moon that’s 100 times more active volcanically than the entire Earth, it’s really quite striking,” he said. “And this was typical of what Voyager was going to do on the rest of its journey through the outer solar system.

“Time after time, we found that nature was much more inventive than our models,” he said.

His wife, Alice, whom he met on a blind date at the University of Chicago and married in 1962, died in December. The couple are survived by their two daughters, Susan and Janet Stone, and two grandsons.

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