One of the best diets for health keeps getting better.

A new study that tracked more than 25,000 women for a quarter century found that the more their eating patterns were in sync with the Mediterranean diet, the less likely they were to die during that period. The relationship held up even when researchers accounted for other factors that influence longevity, including age, exercise habits and smoking history.

The findings were published Friday in the journal JAMA Network Open.

The Mediterranean diet is heavy on fruits, vegetables and whole grains. Extra virgin olive oil, which is rich in antioxidants, is the main source of fat. Protein comes from lean sources like beans, legumes and nuts as well as fish, poultry, eggs and low-fat or fat-free dairy. Wine is welcome in low to moderate amounts, while red and processed meats, butter and sweets are eaten sparingly or not at all.

The diet is a longtime favorite of doctors, nutritionists and weight-loss programs. Studies consistently show that it helps people slim down, reduce cholesterol and lower their blood pressure, all of which reduce the risk of cardiovascular disease. It also helps people manage their blood sugar and stave off Type 2 diabetes.

How, exactly, does the Mediterranean diet pull this off? That’s what Shafqat Ahmad, who studies cardiovascular disease development at Sweden’s Uppsala University and Harvard Medical School, and his colleagues wanted to find out.

They turned to the Women’s Health Study, which enrolled tens of thousands of female health professionals who were at least 45 years old. When the women joined the study in the mid-1990s, they answered 131 questions about the foods they ate.

The researchers used those answers to give each woman a score between 0 and 9 that reflected the degree to which they were following the Mediterranean diet. If they were above the median when it came to consumption of vegetables, fruits, nuts, whole grains, legumes or fish, they got one point. Ditto if they were above the median on their ratio of monounsaturated (which are good) to saturated (which are bad) fatty acids.

If the women were below the median for consumption of red and processed meats, they earned another point. And if they consumed between 5 and 15 grams of alcohol per day — the equivalent of a typical glass of wine or a can of beer — they got a point as well.

Those with total scores between 0 and 3 were categorized as having “low” adherence to the Mediterranean diet. A total of 4 or 5 was classified as “intermediate,” and a sum between 6 and 9 was considered “high.”

The Women’s Health Study ended in 2004, but researchers kept checking in with the participants once a year. Ahmad and his colleagues focused on the 25,315 women who had both diet data and a host of biomedical measurements from when they entered the study.

By November 2023, 3,879 of the women had died. But the risk of being among them wasn’t the same for everyone.

Compared to the women in the low adherence group, those in the intermediate group were 16% less likely to die during the study period, while the risk of death for those with the highest fidelity to the Mediterranean diet was 23% lower, according to the study.

When the researchers controlled for smoking behavior, physical activity, alcohol intake and menopausal factors, women in the intermediate group had an 8% lower risk of death, and those in the high group had an 11% lower risk of death.

In addition to a reduced risk of death from any cause, following the Mediterranean diet was associated with a lower risk of dying of cancer or cardiovascular disease, said Dr. Samia Mora, a cardiologist at Brigham and Women’s Hospital in Boston and the study’s senior author.

As for why the Mediterranean diet seemed to protect against premature death, the most influential factor — among the roughly 40 biomarkers the researchers could test — was a group of metabolites that appeared to explain 14.8% of the benefit. Ahmad and his colleagues called particular attention to higher levels of a useful amino acid called alanine as well as lower levels of another amino acid called homocysteine that is elevated in people with heart disease.

Inflammation accounted for 13% of the mortality benefit enjoyed by those with high adherence to the Mediterranean diet. Chronic inflammation is associated with a variety of health problems, including cardiovascular diseases, diabetes and some cancers.

A woman’s body mass index and a measure of how well her body processes triglycerides were each responsible for 10.2% of the reduced risk of death, and insulin resistance accounted for 7.4%.

The study suggests that making even modest improvements in these factors could help people get more longevity out the Mediterranean diet, Ahmad said.

But he and Mora added that there must be other biological mechanisms at work that their study wasn’t able to measure. The gut microbiome may be one of them, they said.

Dr. Frank Hu, a professor of nutrition and epidemiology at the Harvard T.H. Chan School of Public Health, said the study offers “new insights” into why people who embrace the Mediterranean diet tend to live longer.

“It suggests that the health benefits in reducing mortality are explained by its effects on harmful blood metabolites, inflammation, insulin resistance, and body weight rather than by reducing total and LDL cholesterol,” said Hu, who wasn’t involved in the work.

The study comes with several caveats, including the fact that 96% of the participants were white women. That means the results may not generalize to the population at large.

In addition, the women were asked about their eating habits only once, so there’s no way to know whether their diets changed as they got older.

However, Mercedes Sotos Pietro, a nutritional epidemiologist at the Autonomous University of Madrid, said the findings about the reduced risk of death are in line with research she has conducted using data from the Nurses Health Study and the Health Professionals Follow-up Study that assessed diet multiple times.

Sotos Pietro, who didn’t work on the new study, said the Mediterranean diet is “golden” because it includes a variety of tasty foods and doesn’t forbid anything. That makes it easy for people to stick with it for a long time, she said.

Hu added that the diet’s flexibility makes it adaptable to many cuisines.

“As an example, an Asian individual might use tofu as a protein source and replace white rice with brown rice,” he said. “Individuals can incorporate traditional recipes from other cultures and locally available foods while maintaining the MedDiet‘s key principles.”

After Rachel Somerstein was rushed into an operating room for an unplanned caesarean section, her doctor made the first cut. “I felt that,” she told him. “You’ll feel pressure,” the doctor responded.

But, horrifyingly, Somerstein “felt it all: the separation of my rectus muscles; the scissors used to move my bladder; the scalpel, with which he ‘incised’ my uterus.” When her daughter was born, Somerstein was so traumatized that she couldn’t hold her baby. She screamed for her to be taken from the room.

Friends encouraged Somerstein to file a lawsuit; others balked, doubting that she could have undergone major abdominal surgery without anesthesia. The overarching message to mothers who experience traumatic delivery in this country is to get over it. “How long did it really take,” one attorney asked the author, “five minutes?”

It’s a common refrain: Just be happy you have a healthy baby. The dangerous and potentially unnecessary interventions of medicalized childbirth are never called into question when the pain and trauma of the person giving birth are invalidated. Somerstein quotes two scholars of healthcare and science: “Something is visible [only] when somebody recognizes it as relevant.”

Propelled by Somerstein’s own experience, “Invisible Labor” is a thorough investigation of birthing practices grounded in misogyny, racism and other forces contrary to the well-being of mothers.

Somerstein illuminates the capitalistic drive to rush birth in American hospitals facing infrastructural and staffing deficiencies: “Compared with vaginal births, C-sections are more efficient. Particularly if they are scheduled, a hospital can do far more of them … in a day.”

The medicalization of childbirth, including the C-section, undoubtedly saves lives. But the dehumanization of those giving birth, and the erasure of their well-being and experience, hurts everyone. As “Invisible Labor” shows, the lack of attention and communication in the hospital setting can be fatal.

Somerstein delves into the history of the C-section, which was devised to help save both mother and child. It was quickly adapted by enslavers, however, in “a push to bring about more slaves. In the U.S., most early caesareans took place in the South, and they still do today; a disproportionate number of Black and enslaved women made up the subjects.”

The history of birthing in the U.S. becomes a means of grappling with the history of slavery, racism and eugenics. Once the C-section was in practice, doctors realized that they could also sterilize women of color and those deemed disabled without their consent. “ ‘Acabó la canción,’ said one woman sterilized at L.A. County Hospital in the 1970s. My song has ended.”

Relying on essential feminist texts such as Adrienne Rich’s “Of Woman Born: Motherhood as Experience and Institution,” Somerstein amplifies the role of the midwife — and her removal from the delivery room, taking away a library’s worth of knowledge about birth and birthing people and placing them in largely inexperienced, male hands.

“Just as land gets colonized, so does knowledge,” Barbara Katz Rothman, a sociologist, told Somerstein. “By laying claim to birth, medicine established boundaries over who has authority to attend it.”

Shockingly, Somerstein’s research shows that the electronic fetal monitoring technology used in hospitals, known as EFM, is “notoriously unreliable.” Often, it reports a falling fetal heart rate or stalled labor when the baby and mother are perfectly healthy. But it allows doctors and nurses to tend to many patients, running from room to room and leaving patients alone. Doctors and nurses are trained in the technology instead of the skills of midwives, who know what to look for from extensive experience.

“When used on mothers who have not previously had a caesarean,” Somerstein writes, “EFM, according to one study, makes a person up to 81 percent more likely to have a C-section than mothers monitored intermittently.”

The C-section rate has grown and grown — to about 1 in 3 U.S. births — and “a C-section mom is about 80 percent more likely to have a serious complication, like needing a blood transfusion or an emergency hysterectomy.” Women of color and particularly Black women are more likely to have caesareans.

Speaking to Rei Shimizu, a social work researcher, Somerstein relates: “There’s an assumption in the health system … that nonwhite female bodies cannot give birth safely without intervention.”

“Obstetric racism is about white doctors being racist, but it’s also about doctors, white, Black, whatever, that when you’re expressing your concerns, they just don’t listen,” said Nicole Carr, a professor who spoke to Somerstein about losing her baby after her concerns about her pregnancy were ignored. “It’s a system that makes it so that when you go in and talk about your concerns, it’s almost like you’re not an expert in your own body.”

“Invisible Labor” does not claim that doctors or even medicalized childbirth is the problem. Rather, it’s a system that decenters our humanity and relies on technology and statistics.

“We believe this visual omniscience will fix the problem,” Somerstein writes. “And we discard or forget that events take place outside the frame, including what subjective, embodied knowledge can reveal.”

Women who experience traumatic childbirth are far more likely to suffer from postpartum depression, anxiety or both. Perhaps “attending to women’s pain could be rectified by the simple but radical decision to ask women how they feel and listen to the answer,” Somerstein writes. Instead of telling her “You’ll feel pressure” when he made the incision, her doctor could have asked, “Do you feel pressure?” or, even better, “Do you feel pain?”

Then again, what do we expect in a country whose Supreme Court struck down women’s bodily autonomy? As it stands now, an unborn fetus has more rights than a woman or girl in many states. To create a better system of childbirth for mothers, we have to believe that the rights and indeed the lives of pregnant people matter.

“Invisible Labor” clearly and compassionately blends scientific research and reportage with the personal stories of Somerstein and other women. Childbirth is painful, but with the right care, it can also ground us in our humanity.

Some of the most moving accounts of birth in “Invisible Labor” come from women who had the support of a doula or midwife. When Somerstein writes that “every woman deserves the touch of a midwife,” she is communicating that every person deserves someone who will listen to and validate their experience. This should be the first standard of care.

Jessica Ferri is the owner of Womb House Books and the author, most recently, of “Silent Cities San Francisco.”

Los Angeles could soon end its requirement for city employees to be vaccinated against COVID-19.

City officials are recommending that the Los Angeles City Council halt the requirement as soon as early June, according to a newly released report. The COVID vaccination rule was first approved by city leaders nearly three years ago as public health officials urged vaccination to protect people from the coronavirus.

In a report, City Administrative Officer Matt Szabo noted that other local government agencies — including the cities of Long Beach and San Diego and Los Angeles County — had stopped requiring COVID vaccination as a condition of employment. Szabo said L.A. employee groups had not opposed ending the requirement.

The L.A. ordinance defined “fully vaccinated” as workers having received either one dose of a single shot vaccine, such as the Johnson & Johnson shot, or both doses of a vaccine that required two shots, such as the Moderna or Pfizer vaccines, but said the definition “may be expanded” if health officials required boosters. Under the city ordinance, workers could seek an exemption if they had “a medical condition or restriction or sincerely held religious beliefs.”

If city leaders approve ending the requirements, employees who resigned or were terminated because of the vaccination rule may be eligible to be rehired in the same positions as before.

Eighty-six city workers were terminated under the rule, Szabo said; it is unclear how many employees resigned over the COVID vaccination requirement because they do not have to report their reasons.

Los Angeles has faced numerous lawsuits over its COVID vaccination rule. In one of the latest suits, filed last week in federal court, a woman formerly employed as a city accountant said she was denied a religious exemption from the vaccination requirement and ultimately discharged from her position. She accused the city of discrimination, saying it had ignored its policy of “accommodating sincerely held religious beliefs.”

The move to halt the vaccination requirements comes as the Los Angeles County Department of Public Health has seen a slight uptick in COVID cases, although they cautioned that it was too soon to say if it would become a sustained increase.