Feb 18, 2022 06:41 PM
Weird link discovered between physical attractiveness and the immune system
https://www.sciencealert.com/the-beauty-...-illnesses
INTRO: An extensive new study has found evidence that links physical attractiveness to the functioning of the immune system. While there are still numerous questions left to answer, the researchers suggest their findings show "a relationship between facial attractiveness and immune function is likely to exist." Just how reliable that relationship is remains to be seen, however.
The truth behind beauty is something scientists have been puzzling over since the discovery of evolution. Are social standards of attractiveness in any way affected by the gentle prodding of sexual selection, or is beauty well and truly in the eye of the beholder? The answer is not as simple as choosing one side or the other. Even Charles Darwin, a renowned proponent of natural selection, didn't think beauty was a signal of better health or good genes.
Universal constants of what we all might find to be beautiful have been a constant source of debate, with little consensus on what they might be (let alone if they even exist). Yet throughout history, all sorts of human cultures have deemed certain physical characteristics as attractive, while disregarding others.
While the notion of there being an objective standard of beauty remains contentious, some researchers propose that facial features considered to be attractive could actually be markers of good health, implying that our attraction to them might potentially benefit the survival of our offspring.
It's an intriguing idea in theory, but it lacks quality evidence. Against this backdrop, the authors of the current study say their research is the most rigorous on the topic to date... (MORE - details)
Evolutionary anthropologist Herman Pontzer busts myths about how humans burn calories—and why
https://www.science.org/content/article/...es-and-why
EXCERPTS: . . . By borrowing a method developed by physiologists studying obesity, Pontzer and colleagues systematically measure the total energy used per day by animals and people in various walks of life. The answers coming from their data are often surprising: Exercise doesn’t help you burn more energy on average; active hunter-gatherers in Africa don’t expend more energy daily than sedentary office workers in Illinois; pregnant women don’t burn more calories per day than other adults, after adjusting for body mass.
[...] Pontzer’s skill as a popularizer can rankle some of his colleagues. His message that exercise won’t help you lose weight “lacks nuance,” says exercise physiologist John Thyfault of the University of Kansas Medical Center, who says it may nudge dieters into less healthy habits.
But others say besides busting myths about human energy expenditure, Pontzer’s work offers a new lens for understanding human physiology and evolution. As he wrote in Burn, “In the economics of life, calories are the currency.”
“His work is revolutionary,” says paleoanthropologist Leslie Aiello, past president of the Wenner-Gren Foundation, which has funded Pontzer’s work. “We now have data … that has given us a completely new framework for how we think about how humans adapted to energetic limits.”
[...] Pontzer says the difference in body fat is just as shocking: Male humans pack on twice as much fat as other male apes and women three times as much as other female apes. He thinks our hefty body fat evolved in tandem with our faster metabolic rate: Fat burns less energy than lean tissue and provides a fuel reserve. “Our metabolic engines were not crafted by millions of years of evolution to guarantee a beach-ready bikini body,” Pontzer writes in Burn.
Our ability to convert food and fat stores into energy faster than other apes has important payoffs, however: It gives us more energy every day so we can fuel our big brains as well as feed and protect offspring with long, energetically costly childhoods.
Pontzer thinks characteristically human traits in behavior and anatomy help us maintain amped-up metabolisms. For example, humans routinely share more food with other adults than do other apes. Sharing food is more efficient for the group, and would have given early humans an energy safety net. And our big brains created a positive feedback loop. They demanded more energy but also gave early humans the smarts to invent better tools, control fire, cook, and adapt in other ways to get or save more energy.
[...] Studies of other hunter-gatherer and forager groups have confirmed the Hadza are not an anomaly. Pontzer thinks hunter-gatherers’ bodies adjust for more activity by spending fewer calories on other unseen tasks, such as inflammation and stress responses. “Instead of increasing the calories burned per day, the Hadza’s physical activity was changing the way they spend their calories,” he says.
[...] Pontzer’s findings have a discouraging implication for people wanting to lose weight. ... Thyfault warns that message may do more harm than good. People who exercise are less likely to gain weight in the first place, and those who exercise while they diet tend to keep weight off better, he says. Exercise also can impact where fat is stored on the body and the risk of diabetes and heart disease, he says.
Pontzer agrees that exercise is essential for good health: The Hadza, who are active and fit into their 70s and 80s, don’t get diabetes and heart disease. And, he adds, “If exercise is tamping down the stress response, that compensation is a good thing.” But he says it’s not fair to mislead dieters: “Exercise prevents you from getting sick, but diet is your best tool for weight management.”
[...] Pontzer is now probing a mystery that emerged from his studies of athletes: There seems to be a hard limit on how many calories our bodies can burn per day, set by how fast we can digest food and turn it into energy. He calculates that the ceiling for an 85-kilogram man would be about 4650 calories per day.
[...] To understand how the body can fuel intense exercise or fight off disease without busting energy limits, Pontzer and his students are exploring how the body tamps down other activities... (MORE - missing details)
https://www.sciencealert.com/the-beauty-...-illnesses
INTRO: An extensive new study has found evidence that links physical attractiveness to the functioning of the immune system. While there are still numerous questions left to answer, the researchers suggest their findings show "a relationship between facial attractiveness and immune function is likely to exist." Just how reliable that relationship is remains to be seen, however.
The truth behind beauty is something scientists have been puzzling over since the discovery of evolution. Are social standards of attractiveness in any way affected by the gentle prodding of sexual selection, or is beauty well and truly in the eye of the beholder? The answer is not as simple as choosing one side or the other. Even Charles Darwin, a renowned proponent of natural selection, didn't think beauty was a signal of better health or good genes.
Universal constants of what we all might find to be beautiful have been a constant source of debate, with little consensus on what they might be (let alone if they even exist). Yet throughout history, all sorts of human cultures have deemed certain physical characteristics as attractive, while disregarding others.
While the notion of there being an objective standard of beauty remains contentious, some researchers propose that facial features considered to be attractive could actually be markers of good health, implying that our attraction to them might potentially benefit the survival of our offspring.
It's an intriguing idea in theory, but it lacks quality evidence. Against this backdrop, the authors of the current study say their research is the most rigorous on the topic to date... (MORE - details)
Evolutionary anthropologist Herman Pontzer busts myths about how humans burn calories—and why
https://www.science.org/content/article/...es-and-why
EXCERPTS: . . . By borrowing a method developed by physiologists studying obesity, Pontzer and colleagues systematically measure the total energy used per day by animals and people in various walks of life. The answers coming from their data are often surprising: Exercise doesn’t help you burn more energy on average; active hunter-gatherers in Africa don’t expend more energy daily than sedentary office workers in Illinois; pregnant women don’t burn more calories per day than other adults, after adjusting for body mass.
[...] Pontzer’s skill as a popularizer can rankle some of his colleagues. His message that exercise won’t help you lose weight “lacks nuance,” says exercise physiologist John Thyfault of the University of Kansas Medical Center, who says it may nudge dieters into less healthy habits.
But others say besides busting myths about human energy expenditure, Pontzer’s work offers a new lens for understanding human physiology and evolution. As he wrote in Burn, “In the economics of life, calories are the currency.”
“His work is revolutionary,” says paleoanthropologist Leslie Aiello, past president of the Wenner-Gren Foundation, which has funded Pontzer’s work. “We now have data … that has given us a completely new framework for how we think about how humans adapted to energetic limits.”
[...] Pontzer says the difference in body fat is just as shocking: Male humans pack on twice as much fat as other male apes and women three times as much as other female apes. He thinks our hefty body fat evolved in tandem with our faster metabolic rate: Fat burns less energy than lean tissue and provides a fuel reserve. “Our metabolic engines were not crafted by millions of years of evolution to guarantee a beach-ready bikini body,” Pontzer writes in Burn.
Our ability to convert food and fat stores into energy faster than other apes has important payoffs, however: It gives us more energy every day so we can fuel our big brains as well as feed and protect offspring with long, energetically costly childhoods.
Pontzer thinks characteristically human traits in behavior and anatomy help us maintain amped-up metabolisms. For example, humans routinely share more food with other adults than do other apes. Sharing food is more efficient for the group, and would have given early humans an energy safety net. And our big brains created a positive feedback loop. They demanded more energy but also gave early humans the smarts to invent better tools, control fire, cook, and adapt in other ways to get or save more energy.
[...] Studies of other hunter-gatherer and forager groups have confirmed the Hadza are not an anomaly. Pontzer thinks hunter-gatherers’ bodies adjust for more activity by spending fewer calories on other unseen tasks, such as inflammation and stress responses. “Instead of increasing the calories burned per day, the Hadza’s physical activity was changing the way they spend their calories,” he says.
[...] Pontzer’s findings have a discouraging implication for people wanting to lose weight. ... Thyfault warns that message may do more harm than good. People who exercise are less likely to gain weight in the first place, and those who exercise while they diet tend to keep weight off better, he says. Exercise also can impact where fat is stored on the body and the risk of diabetes and heart disease, he says.
Pontzer agrees that exercise is essential for good health: The Hadza, who are active and fit into their 70s and 80s, don’t get diabetes and heart disease. And, he adds, “If exercise is tamping down the stress response, that compensation is a good thing.” But he says it’s not fair to mislead dieters: “Exercise prevents you from getting sick, but diet is your best tool for weight management.”
[...] Pontzer is now probing a mystery that emerged from his studies of athletes: There seems to be a hard limit on how many calories our bodies can burn per day, set by how fast we can digest food and turn it into energy. He calculates that the ceiling for an 85-kilogram man would be about 4650 calories per day.
[...] To understand how the body can fuel intense exercise or fight off disease without busting energy limits, Pontzer and his students are exploring how the body tamps down other activities... (MORE - missing details)