Health
A Theory of Childbirth’s Evolution May Not Be What You’re Expecting
It’s a question on every new parent’s exhausted mind: Why are babies born so helpless? In 1960, an American anthropologist laid out an influential explanation rooted in human evolution.
As our early ancestors began walking upright, Sherwood Washburn argued in 1960, they evolved a narrower pelvis to make walking long distances more efficient. At the same time, those hominins were evolving larger brains. And babies with big heads could get stuck in a tight birth canal during delivery, threatening the lives of mothers and babies alike.
According to Dr. Washburn, evolution dealt with this “obstetrical dilemma,” as he called it, by shortening pregnancies, so that women delivered babies before the infant brain was done growing.
Dr. Washburn’s theory was hugely influential and became a common lesson in biology classes. “Sapiens: A Brief History of Humankind,” a 2011 best-selling book, presented the obstetrical dilemma as fact. Many researchers still embrace it.
But a detailed review of the evidence, slated to be published soon in the journal Evolutionary Anthropology, threw cold water on the idea. In the review, Anna Warrener, a biological anthropologist at the University of Colorado Denver, argued that the evidence to date did not offer strong support for the obstetrical dilemma, and that scientists had not paid enough attention to possible alternatives. What’s more, the scientist said, the idea sends a pernicious message to women that pregnancy is inherently dangerous.
“It perpetuates a narrative of bodily incompetence,” Dr. Warrener said.
In graduate school, Dr. Warrener did not see any reason to doubt the obstetrical dilemma. For her dissertation, she investigated one of Dr. Washburn’s key assumptions — that women walk less efficiently than men do because their pelvis is wider for childbirth. But in 2015, after studying volunteers walking on treadmills, Dr. Warrener found that having a wider pelvis did not create a bigger demand for oxygen.
“The data came in, and I was like, Wait a minute — I may have gotten some of the story wrong,” she recalled.
Holly Dunsworth, a biological anthropologist now at the University of Rhode Island, also became disenchanted with the obstetrical dilemma when she took a close look at the evidence. “I was scandalized,” she said.
In 2012, she and her colleagues published a study on the length of pregnancies in humans and other primates. They found that, in general, bigger primates tended to have longer pregnancies than smaller ones. For their size, humans don’t have shortened pregnancies. If anything, human pregnancies are longer than one would predict for a primate of their size.
Since then, Dr. Dunsworth has become a strong critic of the obstetrical dilemma, arguing that the timing of childbirth is determined by the size of babies’ bodies, not their heads. The birthing process begins when a fetus demands more energy than a mother’s body can provide, she proposes. “We’re giving birth to massive babies,” she said.
Other scientists, however, have come to the theory’s defense, while admitting that its original conception was overly simplistic.
In a study published last month, a team of researchers argued that the difference between the male and female pelvis shows signs of natural selection acting in different directions. While human males are bigger and taller on average than human females, certain parts of their pelvises are relatively smaller. The biggest differences are in the bones that surround the birth canals in human females.
Despite these differences, the female pelvis still creates a tight fit between a baby’s head and the birth canal, sometimes putting both the baby and mother in peril.
“So why did natural selection not manage to kind of resolve this situation and make birth a little less risky?” asked Nicole Grunstra, an evolutionary anthropologist at the University of Vienna and one of the study’s authors. “It has evolved to be an evolutionary compromise between competing demands,” she said — in other words, to solve an obstetrical dilemma.
But Dr. Grunstra acknowledged flaws in Dr. Washburn’s original version of the theory. She suspected that walking may not have been the most important factor in the evolution of the pelvis. Merely standing upright, she said, might have put pressure on the pelvic floor, preventing the evolution of a more spacious birth canal.
The skeptics aren’t convinced by these arguments. In her new review, Dr. Warrener questioned whether babies getting stuck in birth canals have posed a major threat to women’s lives. It is far more common, she noted, for new mothers to die from blood loss or infections.
She also criticized the way in which Dr. Grunstra and other defenders of the obstetrical dilemma make the case for their hypothesis. In her view, they assume that every piece of human anatomy has been fine-tuned by natural selection for a specific job.
Sometimes, Dr. Warrener said, adaptations are flukes. For example, some of the genes that build the pelvis are also active in the development of other parts of the skeleton. If another bone in our body were to evolve into a new shape, the pelvis might change simply as a byproduct — not because it was evolving for walking or childbirth.
“I think sex differences in the pelvis have been somewhat of a red herring,” Dr. Dunsworth said. Like other bones, the pelvis does not have a fixed shape encoded in a genetic blueprint. Its development is influenced by the tissues around it, including the uterus, the ovaries and other organs. The proportions of the female pelvis may result in part from all the organs that grow inside it.
Both Dr. Dunsworth and Dr. Warrener worry that the obstetrical dilemma leads to a widespread notion of the female body as inescapably defective.
“That just makes us feel like problems that need to be solved by medicine,” Dr. Dunsworth said. That narrative may play a part in the medicalization of childbirth in recent decades, she added.
The World Health Organization has warned that doctors are increasingly performing unnecessary medical intervention on mothers, while chronic disorders that can threaten maternal health — such as high blood pressure, obesity and diabetes — get little attention.
“The way we live now probably doesn’t lead us to meet the challenge of childbirth as well as our bodies did when they developed differently in the past,” Dr. Dunsworth said.
But recognizing the over-medicalization of modern pregnancy doesn’t end the debate about its origins, Dr. Grunstra said. “That does not in itself mean that evolutionary explanations are wrong,” she said.
Health
Jennifer Hudson Lost 80-Lbs Without Depriving Herself—Learn Her Secrets
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Health
Kennedy’s Plan for the Drug Crisis: A Network of ‘Healing Farms’
Though Mr. Kennedy’s embrace of recovery farms may be novel, the concept stretches back almost a century. In 1935, the government opened the United States Narcotic Farm in Lexington, Ky., to research and treat addiction. Over the years, residents included Chet Baker and William S. Burroughs (who portrayed the institution in his novel, “Junkie: Confessions of an Unredeemed Drug Addict”). The program had high relapse rates and was tainted by drug experiments on human subjects. By 1975, as local treatment centers began to proliferate around the country, the program closed.
In America, therapeutic communities for addiction treatment became popular in the 1960s and ’70s. Some, like Synanon, became notorious for cultlike, abusive environments. There are now perhaps 3,000 worldwide, researchers estimate, including one that Mr. Kennedy has also praised — San Patrignano, an Italian program whose centerpiece is a highly regarded bakery, staffed by residents.
“If we do go down the road of large government-funded therapeutic communities, I’d want to see some oversight to ensure they live up to modern standards,” said Dr. Sabet, who is now president of the Foundation for Drug Policy Solutions. “We should get rid of the false dichotomy, too, between these approaches and medications, since we know they can work together for some people.”
Should Mr. Kennedy be confirmed, his authority to establish healing farms would be uncertain. Building federal treatment farms in “depressed rural areas,” as he said in his documentary, presumably on public land, would hit political and legal roadblocks. Fully legalizing and taxing cannabis to pay for the farms would require congressional action.
In the concluding moments of the documentary, Mr. Kennedy invoked Carl Jung, the Swiss psychiatrist whose views on spirituality influenced Alcoholics Anonymous. Dr. Jung, he said, felt that “people who believed in God got better faster and that their recovery was more durable and enduring than people who didn’t.”
Health
Children exposed to higher fluoride levels found to have lower IQs, study reveals
The debate about the benefits and risks of fluoride is ongoing, as RFK Jr. — incoming President Trump’s pick for HHS secretary — pushes to remove it from the U.S. water supply.
“Fluoride is an industrial waste associated with arthritis, bone fractures, bone cancer, IQ loss, neurodevelopmental disorders and thyroid disease,” RFK wrote in a post on X in November.
A new study published in JAMA Pediatrics on Jan. 6 found another correlation between fluoride exposure and children’s IQs.
RFK JR. CALLS FOR REMOVAL OF FLUORIDE FROM DRINKING WATER, SPARKING DEBATE
Study co-author Kyla Taylor, PhD, who is based in North Carolina, noted that fluoridated water has been used “for decades” to reduce dental cavities and improve oral health.
“However, there is concern that pregnant women and children are getting fluoride from many sources, including drinking water, water-added foods and beverages, teas, toothpaste, floss and mouthwash, and that their total fluoride exposure is too high and may affect fetal, infant and child neurodevelopment,” she told Fox News Digital.
The new research, led by scientists at the National Institute of Environmental Health Sciences (NIEHS), analyzed 74 epidemiological studies on children’s IQ and fluoride exposure.
FEDERAL JUDGE ORDERS EPA FURTHER REGULATE FLUORIDE IN DRINKING WATER DUE TO CONCERNS OVER LOWERED IQ IN KIDS
The studies measured fluoride in drinking water and urine across 10 countries, including Canada, China, Denmark, India, Iran, Mexico, Pakistan, New Zealand, Spain and Taiwan. (None were conducted in the U.S.)
The meta-analysis found a “statistically significant association” between higher fluoride exposure and lower children’s IQ scores, according to Taylor.
“[It showed] that the more fluoride a child is exposed to, the more likely that child’s IQ will be lower than if they were not exposed,” she said.
These results were consistent with six previous meta-analyses, all of which reported the same “statistically significant inverse associations” between fluoride exposure and children’s IQs, Taylor emphasized.
The research found that for every 1mg/L increase in urinary fluoride, there was a 1.63-point decrease in IQ.
‘Safe’ exposure levels
The World Health Organization (WHO) has established 1.5mg/L as the “upper safe limit” of fluoride in drinking water.
“There is concern that pregnant women and children are getting fluoride from many sources.”
Meanwhile, the U.S. Public Health Service recommends a fluoride concentration of 0.7 mg/L in drinking water.
“There was not enough data to determine if 0.7 mg/L of fluoride exposure in drinking water affected children’s IQs,” Taylor noted.
FDA BANS RED FOOD DYE DUE TO POTENTIAL CANCER RISK
Higher levels of the chemical can be found in wells and community water serving nearly three million people in the U.S., the researcher noted.
She encouraged pregnant women and parents of small children to be mindful of their total fluoride intake.
“If their water is fluoridated, they may wish to replace tap water with low-fluoride bottled water, like purified water, and limit exposure from other sources, such as dental products or black tea,” she said.
“Parents can use low-fluoride bottled water to mix with powdered infant formula and limit use of fluoridated toothpaste by young children.”
For more Health articles, visit www.foxnews.com/health.
While the research did not intend to address broader public health implications of water fluoridation in the U.S., Taylor suggested that the findings could help inform future research into the impact of fluoride on children’s health.
Dental health expert shares cautions
In response to this study and other previous research, Dr. Ellie Phillips, DDS, an oral health educator based in Austin, Texas, told Fox News Digital that she does not support water fluoridation.
“I join those who vehemently oppose public water fluoridation, and I question why our water supplies are still fluoridated in the 21st century,” she wrote in an email.
“There are non-fluoridated cities and countries where the public enjoy high levels of oral health, which in some cases appear better than those that are fluoridated.”
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Phillips called the fluoride debate “confusing” even among dentists, as the American Dental Association (ADA) advocates for fluoride use for cavity prevention through water fluoridation, toothpaste and mouthwash — “sometimes in high concentrations.”
“[But] biologic (holistic) dentists generally encourage their patients to fear fluoride and avoid its use entirely, even if their teeth are ravaged by tooth decay,” she said.
“Topical fluoride is beneficial, while systemic consumption poses risks.”
Phillips encouraged the public to consider varying fluoride compounds, the effect of different concentrations and the “extreme difference” between applying fluoride topically and ingesting it.
“Topical fluoride is beneficial, while systemic consumption poses risks,” she cautioned.
“Individuals must take charge of their own oral health using natural and informed strategies.”
The study received funding from the National Institute of Environmental Health Sciences (NIEHS), the National Institutes of Health (NIH) and the Intramural Research Program.
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