Studies in neuroscience with applications to humans offer clues about what makes us start eating, and when we stop.Do we really have free will when it comes to eating? It’s a vexing question that is at the heart of why so many people find it so difficult to stick to a diet.To get answers, one neuroscientist, Harvey J. Grill of the University of Pennsylvania, turned to rats and asked what would happen if he removed all of their brains except their brainstems. The brainstem controls basic functions like heart rate and breathing. But the animals could not smell, could not see, could not remember.Would they know when they had consumed enough calories?To find out, Dr. Grill dripped liquid food into their mouths.“When they reached a stopping point, they allowed the food to drain out of their mouths,” he said.Those studies, initiated decades ago, were a starting point for a body of research that has continually surprised scientists and driven home that how full animals feel has nothing to do with consciousness. The work has gained more relevance as scientists puzzle out how exactly the new drugs that cause weight loss, commonly called GLP-1s and including Ozempic, affect the brain’s eating-control systems.The story that is emerging does not explain why some people get obese and others do not. Instead, it offers clues about what makes us start eating, and when we stop.While most of the studies were in rodents, it defies belief to think that humans are somehow different, said Dr. Jeffrey Friedman, an obesity researcher at Rockefeller University in New York. Humans, he said, are subject to billions of years of evolution leading to elaborate neural pathways that control when to eat and when to stop eating.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

Clinical results of a GLP-1 in pill form showed safety and efficacy data similar to blockbuster injectable drugs.A daily pill may be as effective in lowering blood sugar and aiding weight loss in people with Type 2 diabetes as the popular injectable drugs Mounjaro and Ozempic, according to results of a clinical trial announced by Eli Lilly on Thursday morning.The drug, orforglipron, is a GLP-1, a class of drugs that have become blockbusters because of their weight-loss effects. But GLP-1s are expensive, must be kept refrigerated and must be injected. A pill that produces similar results has the potential to become far more widely used.“In the coming decades, 700 million people around the world will have Type 2 diabetes, and over a billion will have obesity,” said Dr. Daniel Skovronsky, Lilly’s chief scientific officer. “Injections cannot be the solution for billions of people around the world.”The results Lilly announced came from a clinical trial involving 559 people with Type 2 diabetes who took the new pill or a placebo for 40 weeks. In patients who took orforglipron, blood sugar levels fell by 1.3 to 1.6 percent, about the same amount in that time period experienced by patients taking Ozempic and Mounjaro in unrelated trials. For 65 percent of people taking the new pill, blood sugar levels dropped into the normal range.Patients on the new pill also lost weight — up to 16 pounds without reaching a plateau at the study’s end. Their weight loss was similar to that achieved in 40 weeks with Ozempic but slightly less than with Mounjaro in unrelated trials.Side effects were the same as those with the injectable obesity drugs — diarrhea, indigestion, constipation, nausea and vomiting.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

Scientists developed a way to freeze a large mammal’s kidney, which could ease organ shortages in the future. First, they had to see if their method would work in a pig.On the last day of March, surgeons at Massachusetts General Hospital began an operation that they hoped might lead to a permanent change in how kidneys are transplanted in people.That morning’s patient was not a person. It was a pig, lying anesthetized on a table. The pig was missing one kidney and needed an implant.While kidneys typically must be transplanted within 24 to 36 hours, the kidney going into the pig had been removed 10 days before, frozen and then thawed early that morning.Never before had anyone transplanted a frozen organ into a large animal. There was so much that could go wrong.“I think there is about a 50 percent chance that it will work,” Korkut Uygun, a professor of surgery and a leader of the team, said before the surgery. Dr. Uygun is on the scientific advisory board of Sylvatica Biotech Inc., a company that is developing freezing methods to preserve organs.But the promise from freezing and storing organs is great.There is a severe and ongoing shortage of kidneys for transplants — more than 92,000 people are on waiting lists. One reason is that the window of 24 to 36 hours is so brief that it limits the number of recipients who are good matches.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

From the “chairs” to the hallway medicine, the show’s depiction of an emergency medicine system that is beyond capacity rings true for medical experts.The emergency department waiting room was jammed, as it always is, with patients sitting for hours, closely packed on hard metal chairs. Only those with conditions so dire they needed immediate care — like a heart attack — got seen immediately.One man had had enough. He pounded on the glass window in front of the receptionist before storming out. As he left, he assaulted a nurse taking a smoking break. “Hard at work?” he called, as he strode off.No, the event was not real, but it was art resembling life on “The Pitt,” the Max series that will stream its season finale on Thursday. The show takes place in a fictional Pittsburgh hospital’s emergency room. But the underlying theme — appalling overcrowding — is universal in this country. And it is not easy to fix.“EDs are gridlocked and overwhelmed,” the American College of Emergency Medicine reported in 2023, referring to emergency departments.“The system is at the breaking point,” said Dr. Benjamin S. Abella, chair of the department of emergency medicine at Mount Sinai’s Icahn School of Medicine in New York.“The Pitt” follows emergency room doctors, nurses, medical students, janitors and staff hour by hour over a single day as they deal with all manner of medical issues, ranging from a child who drowned helping her little sister get out of a swimming pool to a patient with a spider in her ear. There were heart attacks and strokes, overdoses, a patient with severe burns, an influencer poisoned by heavy metals in a skin cream.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

Two significant programs that invested in research on diabetes, dementia, obesity and kidney disease have ended since the start of the Trump administration.Robert F. Kennedy Jr. has spoken of an “existential threat” that he said can destroy the nation.“We have the highest chronic disease burden of any country in the world,” Mr. Kennedy said at a hearing in January before the Senate confirmed him as the secretary of Health and Human Services.And on Monday he is starting a tour in the Southwest to promote a program to combat chronic illness, emphasizing nutrition and lifestyle.But since Mr. Kennedy assumed his post, key grants and contracts that directly address these diseases, including obesity, diabetes and dementia, which experts agree are among the nation’s leading health problems, are being eliminated.These programs range in scale and expense. Researchers warn that their demise could mean lost opportunities to address an aspect of public health that Mr. Kennedy has said is his priority.“This is a huge mistake,” said Dr. Ezekiel Emanuel, the co-director of the Healthcare Transformation Institute at the University of Pennsylvania’s Perelman School of Medicine.Decades of Diabetes Research DiscontinuedEver since its start in 1996, the Diabetes Prevention Program has helped doctors understand this deadly chronic disease. The condition is the nation’s most expensive, affecting 38 million Americans and incurring $306 billion in one recent year in direct costs. With about 400,000 deaths in 2021, it was the eighth leading cause of death.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

The Eli Lilly drug caused a major drop in the blood levels of Lp(a), but further research is needed to show that it will prevent heart attacks and strokes.As many as one in five people — an estimated 64 million in the United States — have elevated levels of a tiny particle in their blood. It can greatly increase the risk of heart attacks and strokes.But few know about it, and almost no doctors test for it, because there was not much to be done. Diet does not help. Neither does exercise. There have been no drugs.But in the near future, that may change.On Sunday, cardiologists announced that an experimental drug made by Eli Lilly, lepodisiran, could lower levels of the particle, Lp(a), by 94 percent with a single injection. The effects lasted for six months and there were no significant side effects.But it is not yet confirmed that reducing Lp(a) levels also reduces the risk of heart attacks and strokes. That awaits large clinical trials that are now underway.The Lilly research was presented Sunday at the annual meeting of the American College of Cardiology and simultaneously published in the New England Journal of Medicine. At least four other companies are also testing innovative drugs that block the body’s production of Lp(a), a mix of lipids and a protein.Dr. David Maron, a preventive cardiologist at Stanford not involved in the Lilly research, said the evidence of profound and long-lasting reduction in lipoprotein levels with lepodisiran was “thrilling.”We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

Senior scientists at the National Institutes of Health fear that research on conditions like obesity, heart disease and cancer will be undermined by President Trump’s policies.A week after Donald J. Trump was inaugurated, a senior scientist at the National Institutes of Health was preparing to give an invited talk at a scientific meeting when an urgent call came in from an administrative assistant.There is a total communications ban, the scientist was told, and you cannot give the speech.As soon as the scientist got back to the office, another ban went into effect — one that prohibited researchers from submitting papers to journals for publication.Seven senior investigators working in different parts of the National Institutes of Health described rules put in place on orders from the Department of Government Efficiency that risk hampering and undermining American medical science. All spoke on the condition of anonymity because they feared for their jobs for speaking publicly.One said that DOGE had begun a reign of “chaos and confusion.” The scientists warned that it had the potential to seriously weaken the N.I.H. — the crown jewel of American science, with a vast network of thousands of researchers in 27 centers dedicated to treating disease, improving health and funding medical research.Rules change seemingly from day to day.Can scientists order necessary supplies to do their research? Yes. No. Maybe.Can they travel? A 30-day ban was put in place on Feb. 26. What happens next? No one knows.“It really is quite chilling,” one of the scientists said. “They are controlling information, causing chaos, disrupting everyone, keeping us off-balance.”We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

Five years after Covid-19 shut down activities all over the world, medical historians sometimes struggle to place the pandemic in context.What, they are asking, should this ongoing viral threat be compared with?Is Covid like the 1918 flu, terrifying when it was raging but soon relegated to the status of a long-ago nightmare?Is it like polio, vanquished but leaving in its wake an injured but mostly unseen group of people who suffer long-term health consequences?Or is it unique in the way it has spawned a widespread rejection of public health advice and science itself, attitudes that some fear may come to haunt the nation when the next major illness arises?Some historians say it is all of the above, which makes Covid stand out in the annals of pandemics.In many ways, historians say, the Covid pandemic — which the World Health Organization declared on March 11, 2020 — reminds them of the 1918 flu. Both were terrifying, killing substantial percentages of the population, unlike, say, polio or Ebola or H.I.V., terrible as those illnesses were.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

The small study in patients with a rare disorder that causes liver and lung damage showed the potential for precisely targeted infusions.Researchers have corrected a disease-causing gene mutation with a single infusion carrying a treatment that precisely targeted the errant gene.This was the first time a mutated gene has been restored to normal.The small study of nine patients announced Monday by the company Beam Therapeutics of Cambridge, Mass., involved fixing a spelling error involving the four base sequences — G, A, C and T — in DNA. The effect was to change an incorrect DNA letter to the right one. The result was a normal gene that functioned as it should, potentially halting liver and lung damage of patients with a rare disorder.“This is the beginning of a new era of medicine,” said Dr. Kiran Musunuru, a gene therapy researcher at the University of Pennsylvania’s Perelman School of Medicine.He added that the method offers the hope of treating other genetic diseases precisely by fixing mutations — an alternative to current gene therapies, which either add new genes to compensate for mutated ones, or slicing DNA to silence genes.Dr. Musunuru is a co-founder and equity holder of Verve Therapeutics, a gene therapy company, and receives funding from Beam Therapeutics for research, but not for this study.Dr. Richard P. Lifton, president of Rockefeller University and head of its Laboratory of Human Genetics and Genomics, said the sort of gene editing Beam did, rewriting genes with an infusion, “is a holy grail” that “has the promise for being a one-and-done kind of therapy.”We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.

Researchers identified a gene that seems to help slow brain aging in women, and studied links between hormone therapy, menopause and Alzheimer’s.Women’s brains are superior to men’s in at least in one respect — they age more slowly. And now, a group of researchers reports that they have found a gene in mice that rejuvenates female brains.Humans have the same gene. The discovery suggests a possible way to help both women and men avoid cognitive declines in advanced age.The study was published Wednesday in the journal Science Advances. The journal also published two other studies on women’s brains, one on the effect of hormone therapy on the brain and another on how age at the onset of menopause shapes the risk of getting Alzheimer’s disease.A gene that slows brain agingThe evidence that women’s brains age more slowly than men’s do seemed compelling.Researchers, looking at the way the brain uses blood sugar, had already found that the brains of aging women are years younger, in metabolic terms, than the brains of aging men.Other scientists, examining markings on DNA, found that female brains are a year or so younger than male brains.And careful cognitive studies of healthy older people found that women had better memories and cognitive function than men of the same age.We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.Thank you for your patience while we verify access.Already a subscriber? Log in.Want all of The Times? Subscribe.