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This one thing may derail your shot at healthy aging, scientists say

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This one thing may derail your shot at healthy aging, scientists say

Before you settle in to binge the new season of “The Bear” or watch Team USA go for the gold at the Paris Olympics, think twice about the amount of time you spend on the couch in front of the TV. Your future self may thank you.

A new study by Harvard researchers links the popular pastime of sitting and watching television to the likelihood of reaching one’s senior years in a state of good health: the more time spent doing the former, the lower the odds of achieving the latter.

The problem doesn’t seem to be with sitting in general. After controlling for a variety of risk factors such as diet quality and smoking history, the researchers found no relationship between time spent in a chair at work and the chances of aging well. Ditto for sitting in cars or at home doing something besides watching TV, such as reading, eating meals or paying bills.

Yet for every additional two hours spent in front of the boob tube, a person’s chance of meeting the researchers’ definition of healthy aging declined by 12%, according to their study published this week in JAMA Network Open.

That does not bode well for the United States, where 62% of adults between the ages of 20 and 64 say they watch TV for at least two hours a day, as do 84% of senior citizens.

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The findings are based on data from more than 45,000 women who participated in the Nurses Heath Study. All of them were at least 50 years old and had no major chronic diseases back in 1992, when they answered a slew of questions about their health and what they did all day.

For instance, the nurses were asked how much time they spent standing or walking around at work or at home. They were asked about various types of exercise, including jogging, swimming laps, playing tennis and doing yoga. They were asked if they mowed their own lawns.

And they were asked how many hours they spent doing all kinds of sitting.

A couple watches a movie on TV at their home in Norwalk while sharing a bowl of popcorn.

(Francine Orr / Los Angeles Times)

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You might not be surprised to learn that the most popular type of sitting was sitting while watching television. More than half of the women — 53% — said they watched between six and 20 hours of TV a week. (The median among this group was around 15.4 hours per week.) Another 15% of the women said they watched between 21 and 40 hours of TV each week, and 2% watched even more.

The nurses were tracked for 20 years or until they died, whichever came first. By the end of the study period, 41% of them were still free of 11 major health conditions, including cancer, diabetes, heart failure, chronic obstructive pulmonary disease and multiple sclerosis. In addition, 44% of the nurses were in good mental health, 52% had no memory impairments and 16% had no physical impairments.

Only 8.6% of the women met all four of those criteria, which was what it took to achieve healthy aging.

On the whole, the women who watched more TV tended to be older, were more likely to be smokers or drinkers, consumed more calories and had higher body mass index scores than women who watched less TV. The more devoted TV watchers were also more likely to have high blood pressure and high cholesterol.

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Once the researchers accounted for these and a host of other differences, they found that the women who spent an hour or less each week sitting in front of the TV were the most likely to achieve healthy aging. Compared to them, women who watched TV for two to five hours per week were 9% less likely to be healthy agers; those who watched for six to 20 hours per week were 19% less likely; those who watched for 21 to 40 hours per week were 40% less likely; and those who watched for at least 41 hours a week were 45% less likely.

The researchers also found that replacing TV time with pretty much anything else — including sleep, for women who got no more than seven hours of shut eye per night — would increase their odds of healthy aging. The more vigorous the new activity, the bigger the boost.

Although the actual percentage of women who succeeded in healthy aging was low, the study authors estimated that another 61% of the women could have joined that rarefied group if they had done four things:

  • Spent at least three hours per day engaged in light physical activity at work.
  • Invested at least 30 minutes a day in moderate to vigorous physical activity.
  • Kept their weight in the normal range instead of being overweight or obese.
  • Limited their TV-watching time to less than three hours a day.

The study didn’t show that excess TV time caused any of the nurses to miss out on healthy aging, only that there was a significant inverse correlation between the two. Still, there’s good reason to suspect that their favorite sedentary behavior bore at least some of the responsibility.

Previous studies have linked prolonged sitting — especially while watching television — to a variety of health problems, including diseases like breast cancer, colorectal cancer, type 2 diabetes, cardiovascular disease and early death. (That particular study found that compared to sitting for less than three hours a day, sitting for at least twice that long was associated with a 17% increased risk of premature death for men and a 34% increased risk of premature death for women.)

But the researchers from Harvard’s T.H. Chan School of Public Health have taken things a step further, said Dr. I-Min Lee, an epidemiologist at Brigham & Women’s Hospital in Boston who studies how physical activity can prevent chronic diseases and extend life.

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“This study expands what we know because it looked at ‘healthy aging,’” said Lee, who was not involved in the study. “‘Health’ is not just the absence of disease; it includes dimensions of physical and mental health, function and well-being.”

All of the study subjects were women, but the biological mechanisms are likely to apply to men as well, Lee said. Even so, it would be good to actually test this relationship in men, as well as in people from a wider range of racial and ethnic backgrounds, she said. (The group of women in the original Nurses Health Study was overwhelmingly white.)

The youngest of the Baby Boomers are now turning 60, and the proportion of the U.S. population that’s at least 65 is projected to increase from roughly 17% today to nearly 21% in 2050, according to the U.S. Census Bureau.

“Population aging is an important public health issue,” the study authors wrote, and strategies to promote healthy aging “are urgently needed.”

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California’s last nuclear plant clears major hurdle to power on

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California’s last nuclear plant clears major hurdle to power on

California environmental regulators on Thursday struck a landmark deal with Pacific Gas & Electric to extend the life of the state’s last remaining nuclear power plant in exchange for thousands of acres of new land conservation in San Luis Obispo County.

PG&E’s agreement with the California Coastal Commission is a key hurdle for the Diablo Canyon nuclear plant to remain online until at least 2030. The plant was slated to close this year, largely due to concerns over seismic safety, but state officials pushed to delay it — saying the plant remains essential for the reliable operation of California’s electrical grid. Diablo Canyon provides nearly 9% of the electricity generated in the state, making it the state’s single largest source.

The Coastal Commission voted 9-3 to approve the plan, settling the fate of some 12,000 acres that surround the power plant as a means of compensation for environmental harm caused by its continued operation.

Nuclear power does not emit greenhouse gases. But Diablo Canyon uses an estimated 2.5 billion gallons of ocean water each day to absorb heat in a process known as “once-through cooling,” which kills an estimated two billion or more marine organisms each year.

Some stakeholders in the region celebrated the conservation deal, while others were disappointed by the decision to trade land for marine impacts — including a Native tribe that had hoped the land would be returned to them. Diablo Canyon sits along one of the most rugged and ecologically rich stretches of the California coast.

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Under the agreement, PG&E will immediately transfer a 4,500-acre parcel on the north side of the property known as the “North Ranch” into a conservation easement and pursue transfer of its ownership to a public agency such as the California Department of Parks and Recreation, a nonprofit land conservation organization or tribe. A purchase by State Parks would result in a more than 50% expansion of the existing Montaña de Oro State Park.

PG&E will also offer a 2,200-acre parcel on the southern part of the property known as “Wild Cherry Canyon” for purchase by a government agency, nonprofit land conservation organization or tribe. In addition, the utility will provide $10 million to plan and manage roughly 25 miles of new public access trails across the entire property.

“It’s going to be something that changes lives on the Central Coast in perpetuity,” Commissioner Christopher Lopez said at the meeting. “This matters to generations that have yet to exist on this planet … this is going to be a place that so many people mark in their minds as a place that transforms their lives as they visit and recreate and love it in a way most of us can’t even imagine today.”

Critically, the plan could see Diablo Canyon remain operational much longer than the five years dictated by Thursday’s agreement. While the state Legislature only authorized the plant to operate through 2030, PG&E’s federal license renewal would cover 20 years of operations, potentially keeping it online until 2045.

Should that happen, the utility would need to make additional land concessions, including expanding an existing conservation area on the southern part of the property known as the “South Ranch” to 2,500 acres. The plan also includes rights of first refusal for a government agency or a land conservation group to purchase the entirety of the South Ranch, 5,000 acres, along with Wild Cherry Canyon — after 2030.

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Pelicans along the concrete breakwater at Pacific Gas and Electric's Diablo Canyon Power Plant

Pelicans along the concrete breakwater at Pacific Gas and Electric’s Diablo Canyon Power Plant

(Brian van der Brug/Los Angeles Times)

Many stakeholders were frustrated by the carve-out for the South Ranch, but still saw the agreement as an overall victory for Californians.

“It is a once in a lifetime opportunity,” Sen. John Laird (D-Santa Cruz) said in a phone call ahead of Thursday’s vote. “I have not been out there where it has not been breathtakingly beautiful, where it is not this incredible, unique location, where you’re not seeing, for much of it, a human structure anywhere. It is just one of those last unique opportunities to protect very special land near the California coast.”

Others, however, described the deal as disappointing and inadequate.

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That includes many of the region’s Native Americans who said they felt sidelined by the agreement. The deal does not preclude tribal groups from purchasing the land in the future, but it doesn’t guarantee that or give them priority.

The yak titʸu titʸu yak tiłhini Northern Chumash Tribe of San Luis Obispo County and Region, which met with the Coastal Commission several times in the lead-up to Thursday’s vote, had hoped to see the land returned to them.

Scott Lanthrop is a member of the tribe’s board and has worked on the issue for several years.

“The sad part is our group is not being recognized as the ultimate conservationist,” he told The Times. “Any normal person, if you ask the question, would you rather have a tribal group that is totally connected to earth and wind and water, or would you like to have some state agency or gigantic NGO manage this land, I think the answer would be, ‘Hey, you probably should give it back to the tribe.’”

Tribe chair Mona Tucker said she fears that free public access to the land could end up harming it instead of helping it, as the Coastal Commission intends.

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“In my mind, I’m not understanding how taking the land … is mitigation for marine life,” Tucker said. “It doesn’t change anything as far as impacts to the water. It changes a lot as far as impacts to the land.”

Montaña de Oro State Park.

Montaña de Oro State Park.

(Christopher Reynolds / Los Angeles Times)

The deal has been complicated by jurisdictional questions, including who can determine what happens to the land. While PG&E owns the North Ranch parcel that could be transferred to State Parks, the South Ranch and Wild Cherry Canyon are owned by its subsidiary, Eureka Energy Company.

What’s more, the California Public Utilities Commission, which regulates utilities such as PG&E, has a Tribal Land Transfer Policy that calls for investor-owned power companies to transfer land they no longer want to Native American tribes.

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In the case of Diablo Canyon, the Coastal Commission became the decision maker because it has the job of compensating for environmental harm from the facility’s continued operation. Since the commission determined Diablo’s use of ocean water can’t be avoided, it looked at land conservation as the next best method.

This “out-of-kind” trade-off is a rare, but not unheard of way of making up for the loss of marine life. It’s an approach that is “feasible and more likely to succeed” than several other methods considered, according to the commission’s staff report.

“This plan supports the continued operation of a major source of reliable electricity for California, and is in alignment with our state’s clean energy goals and focus on coastal protection,” Paula Gerfen, Diablo Canyon’s senior vice president and chief nuclear officer, said in a statement.

But Assemblymember Dawn Addis (D-Morro Bay) said the deal was “not the best we can do” — particularly because the fate of the South Ranch now depends on the plant staying in operation beyond 2030.

“I believe the time really is now for the immediate full conservation of the 12,000 [acres], and to bring accountability and trust back for the voters of San Luis Obispo County,” Addis said during the meeting.

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There are also concerns about the safety of continuing to operate a nuclear plant in California, with its radioactive waste stored in concrete casks on the site. Diablo Canyon is subject to ground shaking and earthquake hazards, including from the nearby Hosgri Fault and the Shorline Fault, about 2.5 miles and 1 mile from the facility, respectively.

PG&E says the plant has been built to withstand hazards. It completed a seismic hazard assessment in 2024, and determined Diablo Canyon is safe to continue operation through 2030. The Coastal Commission, however, found if the plant operates longer, it would warrant further seismic study.

A key development for continuing Diablo Canyon’s operation came in 2022 with Senate Bill 846, which delayed closure by up to five additional years. At the time, California was plagued by rolling blackouts driven extreme heat waves, and state officials were growing wary about taking such a major source of power offline.

But California has made great gains in the last several years — including massive investments in solar energy and battery storage — and some questioned whether the facility is still needed at all.

Others said conserving thousands of acres of land still won’t make up for the harms to the ocean.

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“It is unmitigatable,” said David Weisman, executive director of the nonprofit Alliance for Nuclear Responsibility. He noted that the Coastal Commission’s staff report says it would take about 99 years to balance the loss of marine life with the benefits provided by 4,500 acres of land conservation. Twenty more years of operation would take about 305 years to strike that same balance.

But some pointed out that neither the commission nor fisheries data find Diablo’s operations cause declines in marine life. Ocean harm may be overestimated, said Seaver Wang, an oceanographer and the climate and energy director at the Breakthrough Institute, a Berkeley-based research center.

In California’s push to transition to clean energy, every option comes with downsides, Wang said. In the case of nuclear power — which produces no greenhouse gas emissions — it’s all part of the trade off, he said.

“There’s no such thing as impacts-free energy,” he said.

The Coastal Commission’s vote is one of the last remaining obstacles to keeping the plant online. PG&E will also need a final nod from the Regional Water Quality Control Board, which decides on a pollution discharge permit in February.

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The federal Nuclear Regulatory Commission will also have to sign off on Diablo’s extension.

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In search for autism’s causes, look at genes, not vaccines, researchers say

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In search for autism’s causes, look at genes, not vaccines, researchers say

Earlier this year, Health and Human Services Secretary Robert F. Kennedy Jr. pledged that the search for autism’s cause — a question that has kept researchers busy for the better part of six decades — would be over in just five months.

“By September, we will know what has caused the autism epidemic, and we’ll be able to eliminate those exposures,” Kennedy told President Trump during a Cabinet meeting in April.

That ambitious deadline has come and gone. But researchers and advocates say that Kennedy’s continued fixation on autism’s origins — and his frequent, inaccurate claims that childhood vaccines are somehow involved — is built on fundamental misunderstandings of the complex neurodevelopmental condition.

Even after more than half a century of research, no one yet knows exactly why some people have autistic traits and others do not, or why autism spectrum disorder looks so different across the people who have it. But a few key themes have emerged.

Researchers believe that autism is most likely the result of a complex set of interactions between genes and the environment that unfold while a child is in the womb. It can be passed down through families, or originate with a spontaneous gene mutation.

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Environmental influences may indeed play a role in some autism cases, but their effect is heavily influenced by a person’s genes. There is no evidence for a single trigger that causes autism, and certainly not one a child encounters after birth: not a vaccine, a parenting style or a post-circumcision Tylenol.

“The real reason why it’s complicated, the more fundamental one, is that there’s not a single cause,” said Irva Hertz-Picciotto, a professor of public health science and director of the Environmental Health Sciences Center at UC Davis. “It’s not a single cause from one person to the next, and not a single cause within any one person.”

Kennedy, an attorney who has no medical or scientific training, has called research into autism’s genetics a “dead end.” Autism researchers counter that it’s the only logical place to start.

“If we know nothing else, we know that autism is primarily genetic,” said Joe Buxbaum, a molecular neuroscientist who directs the Seaver Autism Center for Research and Treatment at the Icahn School of Medicine at Mount Sinai. “And you don’t have to actually have the exact genes [identified] to know that something is genetic.”

Some neurodevelopment disorders arise from a difference in a single gene or chromosome. People with Down syndrome have an extra copy of chromosome 21, for example, and Fragile X syndrome results when the FMR1 gene isn’t expressed.

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Autism in most cases is polygenetic, which means that multiple genes are involved, with each contributing a little bit to the overall picture.

Researchers have found hundreds of genes that could be associated with autism; there may be many more among the roughly 20,000 in the human genome.

In the meantime, the strongest evidence that autism is genetic comes from studies of twins and other sibling groups, Buxbaum and other researchers said.

The rate of autism in the U.S. general population is about 2.8%, according to a study published last year in the journal Pediatrics. Among children with at least one autistic sibling, it’s 20.2% — about seven times higher than the general population, the study found.

Twin studies reinforce the point. Both identical and fraternal twins develop in the same womb and are usually raised in similar circumstances in the same household. The difference is genetic: identical twins share 100% of their genetic information, while fraternal twins share about 50% (the same as nontwin siblings).

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If one fraternal twin is autistic, the chance that the other twin is also autistic is about 20%, or about the same as it would be for a nontwin sibling.

But if one in a pair of identical twins is autistic, the chance that the other twin is also autistic is significantly higher. Studies have pegged the identical twin concurrence rate anywhere from 60% to 90%, though the intensity of the twins’ autistic traits may differ significantly.

Molecular genetic studies, which look at the genetic information shared between siblings and other blood relatives, have found similar rates of genetic influence on autism, said Dr. John Constantino, a professor of pediatrics, psychiatry and behavioral sciences at the Emory University School of Medicine and chief of behavioral and mental health at Children’s Healthcare of Atlanta.

Together, he said, “those studies have indicated that a vast share of the causation of autism can be traced to the effects of genetic influences. That is a fact.”

Buxbaum compares the heritability of autism to the heritability of height, another polygenic trait.

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“There’s not one gene that’s making you taller or shorter,” Buxbaum said. Hundreds of genes play a role in where you land on the height distribution curve. A lot of those genes run in families — it’s not unusual for very tall people, for example, to have very tall relatives.

But parents pass on a random mix of their genes to their children, and height distribution across a group of same-sex siblings can vary widely. Genetic mutations can change the picture. Marfan syndrome, a condition caused by mutations in the FBN1 gene, typically makes people grow taller than average. Hundreds of genetic mutations are associated with dwarfism, which causes shorter stature.

Then once a child is born, external factors such as malnutrition or disease can affect the likelihood that they reach their full height potential.

So genes are important. But the environment — which in developmental science means pretty much anything that isn’t genetics, including parental age, nutrition, air pollution and viruses — can play a major role in how those genes are expressed.

“Genetics does not operate in a vacuum, and at the same time, the impact of the environment on people is going to depend on a person’s individual genetics,” said Brian K. Lee, a professor of epidemiology and biostatistics at Drexel University who studies the genetics of developmental disorders.

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Unlike the childhood circumstances that can affect height, the environmental exposures associated with autism for the most part take place in utero.

Researchers have identified multiple factors linked to increased risks of the disorder, including older parental age, infant prematurity and parental exposure to air pollution and industrial solvents.

Investigations into some of these linkages were among the more than 50 autism-related studies whose funding Kennedy has cut since taking office, a ProPublica investigation found. In contrast, no credible study has found links between vaccines and autism — and there have been many.

One move from the Department of Health and Human Services has been met with cautious optimism: even as Kennedy slashed funding to other research projects, the department in September announced a $50-million initiative to explore the interactions of genes and environmental factors in autism, which has been divided among 13 different research groups at U.S. universities, including UCLA and UC San Diego.

The department’s selection of well-established, legitimate research teams was met with relief by many autism scientists.

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But many say they fear that such decisions will be an anomaly under Kennedy, who has repeatedly rejected facts that don’t conform to his preferred hypotheses, elevated shoddy science and muddied public health messaging on autism with inaccurate information.

Disagreements are an essential part of scientific inquiry. But the productive ones take place in a universe of shared facts and build on established evidence.

And when determining how to spend limited resources, researchers say, making evidence-based decisions is vital.

“There are two aspects of these decisions: Is it a reasonable expenditure based on what we already know? And if you spend money here, will you be taking money away from HHS that people are in desperate need of?” Constantino said. “If you’re going to be spending money, you want to do that in a way that is not discarding what we already know.”

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Contributor: New mothers are tempted by Ozempic but don’t have the data they need

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Contributor: New mothers are tempted by Ozempic but don’t have the data they need

My friend Sara, eight weeks after giving birth, left me a tearful voicemail. I’m a clinical psychologist specializing in postpartum depression and psychosis, but mental health wasn’t Sara’s issue. Postpartum weight gain was.

Sara told me she needed help. She’d gained 40 pounds during her pregnancy, and she was still 25 pounds overweight. “I’m going back to work and I can’t look like this,” she said. “I need to take Ozempic or something. But do you know if it’s safe?”

Great question. Unfortunately researchers don’t yet have an answer. On Dec. 1, the World Health Organization released its first guidelines on the use of GLP-1 receptor agonists such as Ozempic, generically known as semaglutide. One of the notable policy suggestions in that report is to not prescribe GLP-1s to pregnant women. Disappointingly, the report says nothing about the use of the drug by postpartum women, including those who are breastfeeding.

There was a recent Danish study that led to medical guidelines against prescribing to patients who are pregnant or breastfeeding.

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None of that is what my friend wanted to hear. I could only encourage her to speak to her own medical doctor.

Sara’s not alone. I’ve seen a trend emerging in my practice in which women use GLP-1s to shed postpartum weight. The warp speed “bounce-back” ideal of body shapes for new mothers has reemerged, despite the mental health field’s advocacy to abolish the archaic pressure of martyrdom in motherhood. GLP-1s are being sold and distributed by compound pharmacies like candy. And judging by their popularity, nothing tastes sweeter than skinny feels.

New motherhood can be a stressful time for bodies and minds, but nature has also set us up for incredible growth at that moment. Contrary to the myth of spaced-out “mommy brains,” new neuroplasticity research shows that maternal brains are rewired for immense creativity and problem solving.

How could GLP-1s affect that dynamic? We just don’t know. We do know that these drugs are associated with changes far beyond weight loss, potentially including psychiatric effects such as combating addiction.

Aside from physical effects, this points to an important unanswered research question: What effects, if any, do GLP-1s have on a woman’s brain as it is rewiring to attune to and take care of a newborn? And on a breastfeeding infant? If GLP-1s work on the pleasure center of the brain and your brain is rewiring to feel immense pleasure from a baby coo, I can’t help but wonder if that will be dampened. When a new mom wants a prescription for a GLP-1 to help shed baby weight, her medical provider should emphasize those unknowns.

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These drugs may someday be a useful tool for new mothers. GLP-1s are helping many people with conditions other than obesity. A colleague of mine was born with high blood pressure and cholesterol. She exercised every day and adopted a pescatarian diet. Nothing budged until she added a GLP-1 to her regimen, bringing her blood pressure to a healthy 120/80 and getting cholesterol under control. My brother, an otherwise healthy young man recently diagnosed with a rare idiopathic lymphedema of his left leg, is considering GLP-1s to address inflammation and could be given another chance at improving his quality of life.

I hope that GLP-1s will continue to help those who need it. And I urge everyone — especially new moms — to proceed with caution. A healthy appetite for nutritious food is natural. That food fuels us for walks with our dogs, swims along a coastline, climbs through leafy woods. It models health and balance for the young ones who are watching us for clues about how to live a healthy life.

Nicole Amoyal Pensak, a clinical psychologist and researcher, is the author of “Rattled: How to Calm New Mom Anxiety With the Power of the Postpartum Brain.”

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