Latest news with #Hadza
Yahoo
15-07-2025
- Health
- Yahoo
What causes obesity? A major new study is upending common wisdom.
Obesity is uncommon among Hadza hunter-gatherers in Tanzania, Tsimane forager-farmers in Bolivia, Tuvan herder-farmers in Siberia, and other people in less-developed nations. But it's widespread among those of us in wealthy, highly industrialized nations. Why? A major study published this week in PNAS brings surprising clarity to that question. Using objective data about metabolic rates and energy expenditure among more than 4,000 men and women living in dozens of nations across a broad spectrum of socioeconomic conditions, the study quantified how many calories people from different cultures burn most days. Subscribe to The Post Most newsletter for the most important and interesting stories from The Washington Post. For decades, common wisdom and public health messaging have assumed that people in highly developed nations, like the United States, are relatively sedentary and burn far fewer daily calories than people in less-industrialized countries, greatly increasing the risk for obesity. But the new study says no. Instead, it finds that Americans, Europeans and people living in other developed nations expend about the same number of total calories most days as hunter-gatherers, herders, subsistence farmers, foragers and anyone else living in less-industrialized nations. That unexpected finding almost certainly means inactivity is not the main cause of obesity in the U.S. and elsewhere, said Herman Pontzer, a professor of evolutionary anthropology and global health at Duke University in North Carolina and a senior author of the new study. What is, then? The study offers provocative hints about the role of diet and some of the specific foods we eat, as well as about the limits of exercise, and the best ways, in the long run, to avoid and treat obesity. - - - Is diet or inactivity causing obesity? 'There's still a lively debate in public health about the role of diet and activity' in the development of obesity, Pontzer said, especially in wealthy nations. Some experts believe we're exercising too little, others that we're eating too much, and still more that the two contribute almost equally. Understanding the relative contributions of diet and physical activity is important, Pontzer noted, because we can't effectively help people with obesity unless we first tease out its origins. But few large-scale studies have carefully compared energy expenditure among populations prone to obesity against those more resistant to it, which would be a first step toward figuring out what drives weight gain. So, for the new study, Pontzer and his 80-plus co-authors gathered existing data from labs around the world that use doubly labeled water in metabolism studies. Doubly labeled water contains isotopes that, when excreted in urine or other fluids, allow researchers to precisely determine someone's energy expenditure, metabolic rates and body-fat percentage. It's the gold standard in this kind of research. They wound up with data for 4,213 men and women from 34 countries or cultural groups, running the socioeconomic gamut from tribes in Africa to executives in Norway. They calculated total daily energy expenditures for everyone, along with their basal energy expenditure, which is the number of calories our bodies burn during basic, biological operations, and physical activity energy expenditure, which is how many calories we use while moving around. - - - A new theory of how our metabolisms work After adjusting for body size (since people in wealthy nations tend to have larger bodies, and larger bodies burn more calories), they started comparing different groups. Anyone expecting a wide range of energy expenditures, with hunter-gatherers and farmer-herders at the high end and deskbound American office workers trailing well behind, would be wrong. Across the board, the total daily energy expenditures of the 4,213 people were quite similar, no matter where they lived or how they spent their lives. Although the hunter-gatherers and other similar groups moved around far more throughout the day than a typical American, their overall daily calorie burns were nearly the same. The findings, though counterintuitive, align with a new theory about our metabolisms, first proposed by Pontzer. Known as the constrained total energy expenditure model, it says that our brains and bodies closely monitor our total energy expenditure, keeping it within a narrow range. If we start consistently burning extra calories by, for instance, stalking prey on foot for days or training for a marathon, our brains slow down or shut off some tangential biological operations, often related to growth, and our overall daily calorie burn stays within a consistent band. - - - The role of ultra-processed foods The upshot is that 'there is no effect of economic development on size-adjusted physical activity expenditure,' Pontzer says. In which case, the fundamental problem isn't that we're moving too little, meaning more exercise is unlikely to reduce obesity much. What could, then? 'Our analyses suggest that increased energy intake has been roughly 10 times more important than declining total energy expenditure in driving the modern obesity crisis,' the study authors write. In other words, we're eating too much. We may also be eating the wrong kinds of foods, the study also suggests. In a sub-analysis of the diets of some of the groups from both highly and less-developed nations, the scientists found a strong correlation between the percentage of daily diets that consists of 'ultra-processed foods' - which the study's authors define as 'industrial formulations of five or more ingredients' - and higher body-fat percentages. We are, to be blunt, eating too much and probably eating too much of the wrong foods. 'This study confirms what I've been saying, which is that diet is the key culprit in our current [obesity] epidemic,' said Barry Popkin, a professor at the Gillings School of Global Public Health at the University of North Carolina at Chapel Hill and an obesity expert. 'This is a well-done study,' he added. Other experts agree. 'It's clear from this important new research and other studies that changes to our food, not our activity, are the dominant drivers of obesity,' said Dariush Mozaffarian, director of the Food is Medicine Institute at Tufts University in Boston. The findings don't mean, though, that exercise is unimportant, Pontzer emphasized. 'We know that exercise is essential for health. This study doesn't change that,' he said. But the study does suggest that 'to address obesity, public health efforts need to focus on diet,' he said, especially on ultra-processed foods, 'that seem to be really potent causes of obesity.' Related Content He may have stopped Trump's would-be assassin. Now he's telling his story. He seeded clouds over Texas. Then came the conspiracy theories. How conservatives beat back a Republican sell-off of public lands
Yahoo
15-07-2025
- Health
- Yahoo
What causes obesity? A major new study is upending common wisdom.
Obesity is uncommon among Hadza hunter-gatherers in Tanzania, Tsimane forager-farmers in Bolivia, Tuvan herder-farmers in Siberia, and other people in less-developed nations. But it's widespread among those of us in wealthy, highly industrialized nations. Why? A major study published this week in PNAS brings surprising clarity to that question. Using objective data about metabolic rates and energy expenditure among more than 4,000 men and women living in dozens of nations across a broad spectrum of socioeconomic conditions, the study quantified how many calories people from different cultures burn most days. Subscribe to The Post Most newsletter for the most important and interesting stories from The Washington Post. For decades, common wisdom and public health messaging have assumed that people in highly developed nations, like the United States, are relatively sedentary and burn far fewer daily calories than people in less-industrialized countries, greatly increasing the risk for obesity. But the new study says no. Instead, it finds that Americans, Europeans and people living in other developed nations expend about the same number of total calories most days as hunter-gatherers, herders, subsistence farmers, foragers and anyone else living in less-industrialized nations. That unexpected finding almost certainly means inactivity is not the main cause of obesity in the U.S. and elsewhere, said Herman Pontzer, a professor of evolutionary anthropology and global health at Duke University in North Carolina and a senior author of the new study. What is, then? The study offers provocative hints about the role of diet and some of the specific foods we eat, as well as about the limits of exercise, and the best ways, in the long run, to avoid and treat obesity. - - - Is diet or inactivity causing obesity? 'There's still a lively debate in public health about the role of diet and activity' in the development of obesity, Pontzer said, especially in wealthy nations. Some experts believe we're exercising too little, others that we're eating too much, and still more that the two contribute almost equally. Understanding the relative contributions of diet and physical activity is important, Pontzer noted, because we can't effectively help people with obesity unless we first tease out its origins. But few large-scale studies have carefully compared energy expenditure among populations prone to obesity against those more resistant to it, which would be a first step toward figuring out what drives weight gain. So, for the new study, Pontzer and his 80-plus co-authors gathered existing data from labs around the world that use doubly labeled water in metabolism studies. Doubly labeled water contains isotopes that, when excreted in urine or other fluids, allow researchers to precisely determine someone's energy expenditure, metabolic rates and body-fat percentage. It's the gold standard in this kind of research. They wound up with data for 4,213 men and women from 34 countries or cultural groups, running the socioeconomic gamut from tribes in Africa to executives in Norway. They calculated total daily energy expenditures for everyone, along with their basal energy expenditure, which is the number of calories our bodies burn during basic, biological operations, and physical activity energy expenditure, which is how many calories we use while moving around. - - - A new theory of how our metabolisms work After adjusting for body size (since people in wealthy nations tend to have larger bodies, and larger bodies burn more calories), they started comparing different groups. Anyone expecting a wide range of energy expenditures, with hunter-gatherers and farmer-herders at the high end and deskbound American office workers trailing well behind, would be wrong. Across the board, the total daily energy expenditures of the 4,213 people were quite similar, no matter where they lived or how they spent their lives. Although the hunter-gatherers and other similar groups moved around far more throughout the day than a typical American, their overall daily calorie burns were nearly the same. The findings, though counterintuitive, align with a new theory about our metabolisms, first proposed by Pontzer. Known as the constrained total energy expenditure model, it says that our brains and bodies closely monitor our total energy expenditure, keeping it within a narrow range. If we start consistently burning extra calories by, for instance, stalking prey on foot for days or training for a marathon, our brains slow down or shut off some tangential biological operations, often related to growth, and our overall daily calorie burn stays within a consistent band. - - - The role of ultra-processed foods The upshot is that 'there is no effect of economic development on size-adjusted physical activity expenditure,' Pontzer says. In which case, the fundamental problem isn't that we're moving too little, meaning more exercise is unlikely to reduce obesity much. What could, then? 'Our analyses suggest that increased energy intake has been roughly 10 times more important than declining total energy expenditure in driving the modern obesity crisis,' the study authors write. In other words, we're eating too much. We may also be eating the wrong kinds of foods, the study also suggests. In a sub-analysis of the diets of some of the groups from both highly and less-developed nations, the scientists found a strong correlation between the percentage of daily diets that consists of 'ultra-processed foods' - which the study's authors define as 'industrial formulations of five or more ingredients' - and higher body-fat percentages. We are, to be blunt, eating too much and probably eating too much of the wrong foods. 'This study confirms what I've been saying, which is that diet is the key culprit in our current [obesity] epidemic,' said Barry Popkin, a professor at the Gillings School of Global Public Health at the University of North Carolina at Chapel Hill and an obesity expert. 'This is a well-done study,' he added. Other experts agree. 'It's clear from this important new research and other studies that changes to our food, not our activity, are the dominant drivers of obesity,' said Dariush Mozaffarian, director of the Food is Medicine Institute at Tufts University in Boston. The findings don't mean, though, that exercise is unimportant, Pontzer emphasized. 'We know that exercise is essential for health. This study doesn't change that,' he said. But the study does suggest that 'to address obesity, public health efforts need to focus on diet,' he said, especially on ultra-processed foods, 'that seem to be really potent causes of obesity.' Related Content He may have stopped Trump's would-be assassin. Now he's telling his story. He seeded clouds over Texas. Then came the conspiracy theories. How conservatives beat back a Republican sell-off of public lands
Yahoo
15-07-2025
- Health
- Yahoo
What causes obesity? A major new study is upending common wisdom.
Obesity is uncommon among Hadza hunter-gatherers in Tanzania, Tsimane forager-farmers in Bolivia, Tuvan herder-farmers in Siberia, and other people in less-developed nations. But it's widespread among those of us in wealthy, highly industrialized nations. Why? A major study published this week in PNAS brings surprising clarity to that question. Using objective data about metabolic rates and energy expenditure among more than 4,000 men and women living in dozens of nations across a broad spectrum of socioeconomic conditions, the study quantified how many calories people from different cultures burn most days. Subscribe to The Post Most newsletter for the most important and interesting stories from The Washington Post. For decades, common wisdom and public health messaging have assumed that people in highly developed nations, like the United States, are relatively sedentary and burn far fewer daily calories than people in less-industrialized countries, greatly increasing the risk for obesity. But the new study says no. Instead, it finds that Americans, Europeans and people living in other developed nations expend about the same number of total calories most days as hunter-gatherers, herders, subsistence farmers, foragers and anyone else living in less-industrialized nations. That unexpected finding almost certainly means inactivity is not the main cause of obesity in the U.S. and elsewhere, said Herman Pontzer, a professor of evolutionary anthropology and global health at Duke University in North Carolina and a senior author of the new study. What is, then? The study offers provocative hints about the role of diet and some of the specific foods we eat, as well as about the limits of exercise, and the best ways, in the long run, to avoid and treat obesity. - - - Is diet or inactivity causing obesity? 'There's still a lively debate in public health about the role of diet and activity' in the development of obesity, Pontzer said, especially in wealthy nations. Some experts believe we're exercising too little, others that we're eating too much, and still more that the two contribute almost equally. Understanding the relative contributions of diet and physical activity is important, Pontzer noted, because we can't effectively help people with obesity unless we first tease out its origins. But few large-scale studies have carefully compared energy expenditure among populations prone to obesity against those more resistant to it, which would be a first step toward figuring out what drives weight gain. So, for the new study, Pontzer and his 80-plus co-authors gathered existing data from labs around the world that use doubly labeled water in metabolism studies. Doubly labeled water contains isotopes that, when excreted in urine or other fluids, allow researchers to precisely determine someone's energy expenditure, metabolic rates and body-fat percentage. It's the gold standard in this kind of research. They wound up with data for 4,213 men and women from 34 countries or cultural groups, running the socioeconomic gamut from tribes in Africa to executives in Norway. They calculated total daily energy expenditures for everyone, along with their basal energy expenditure, which is the number of calories our bodies burn during basic, biological operations, and physical activity energy expenditure, which is how many calories we use while moving around. - - - A new theory of how our metabolisms work After adjusting for body size (since people in wealthy nations tend to have larger bodies, and larger bodies burn more calories), they started comparing different groups. Anyone expecting a wide range of energy expenditures, with hunter-gatherers and farmer-herders at the high end and deskbound American office workers trailing well behind, would be wrong. Across the board, the total daily energy expenditures of the 4,213 people were quite similar, no matter where they lived or how they spent their lives. Although the hunter-gatherers and other similar groups moved around far more throughout the day than a typical American, their overall daily calorie burns were nearly the same. The findings, though counterintuitive, align with a new theory about our metabolisms, first proposed by Pontzer. Known as the constrained total energy expenditure model, it says that our brains and bodies closely monitor our total energy expenditure, keeping it within a narrow range. If we start consistently burning extra calories by, for instance, stalking prey on foot for days or training for a marathon, our brains slow down or shut off some tangential biological operations, often related to growth, and our overall daily calorie burn stays within a consistent band. - - - The role of ultra-processed foods The upshot is that 'there is no effect of economic development on size-adjusted physical activity expenditure,' Pontzer says. In which case, the fundamental problem isn't that we're moving too little, meaning more exercise is unlikely to reduce obesity much. What could, then? 'Our analyses suggest that increased energy intake has been roughly 10 times more important than declining total energy expenditure in driving the modern obesity crisis,' the study authors write. In other words, we're eating too much. We may also be eating the wrong kinds of foods, the study also suggests. In a sub-analysis of the diets of some of the groups from both highly and less-developed nations, the scientists found a strong correlation between the percentage of daily diets that consists of 'ultra-processed foods' - which the study's authors define as 'industrial formulations of five or more ingredients' - and higher body-fat percentages. We are, to be blunt, eating too much and probably eating too much of the wrong foods. 'This study confirms what I've been saying, which is that diet is the key culprit in our current [obesity] epidemic,' said Barry Popkin, a professor at the Gillings School of Global Public Health at the University of North Carolina at Chapel Hill and an obesity expert. 'This is a well-done study,' he added. Other experts agree. 'It's clear from this important new research and other studies that changes to our food, not our activity, are the dominant drivers of obesity,' said Dariush Mozaffarian, director of the Food is Medicine Institute at Tufts University in Boston. The findings don't mean, though, that exercise is unimportant, Pontzer emphasized. 'We know that exercise is essential for health. This study doesn't change that,' he said. But the study does suggest that 'to address obesity, public health efforts need to focus on diet,' he said, especially on ultra-processed foods, 'that seem to be really potent causes of obesity.' Related Content He may have stopped Trump's would-be assassin. Now he's telling his story. He seeded clouds over Texas. Then came the conspiracy theories. How conservatives beat back a Republican sell-off of public lands
Washington Post
15-07-2025
- Health
- Washington Post
What causes obesity? A major new study is upending common wisdom.
Obesity is uncommon among Hadza hunter-gatherers in Tanzania, Tsimane forager-farmers in Bolivia, Tuvan herder-farmers in Siberia, and other people in less-developed nations. But it's widespread among those of us in wealthy, highly industrialized nations. Why? A major study published this week in PNAS brings surprising clarity to that question. Using objective data about metabolic rates and energy expenditure among more than 4,000 men and women living in dozens of nations across a broad spectrum of socioeconomic conditions, the study quantified how many calories people from different cultures burn most days.
New York Post
20-05-2025
- Health
- New York Post
Having trouble sleeping? 4 ways sleeping like a caveman can cure insomnia
Yabba dabba snooze! Sleep is essential for physical and mental health — it's crucial for brain function, memory consolidation, tissue repair, immune system maintenance, concentration, hormone regulation and stress management. Unfortunately, more than a third of American adults don't get enough rest. Inadequate sleep has been linked to cognitive troubles, a weakened immune system, weight gain, depression and a higher risk of chronic illnesses like heart disease, diabetes and high blood pressure. Advertisement Dutch sleep scientist and recovering insomniac Merijn van de Laar suggests that our ancestors may hold the key to sleeping like a rock. 4 Dutch sleep scientist Merijn van de Laar wrote the new book, 'How to Sleep Like a Caveman.' Courtesy of Merijn van de Laar 'Sleep has hardly changed since Paleolithic humans snoozed soundly in their caves,' van de Laar notes in his new book, 'How to Sleep Like a Caveman.' Advertisement 'While saber-toothed tigers were their biggest night-time worry, today it's stress and social media that keep us awake, but the solutions are the same,' he added. Van de Laar shares four suggestions for getting a better night's sleep in three weeks — cave not required. Let go of the eight-hour rule Experts generally recommend adults snooze between seven and nine hours a night. Van de Laar said it's OK to get six. Advertisement 'The average length of subjective sleep is between just under six hours and almost 7.5 hours,' he told The Post. 'Sleeping six hours is generally not more associated with health problems when compared to sleeping eight hours.' 4 Experts generally recommend adults snooze between seven and nine hours a night. Van de Laar said it's OK to get six. Jelena – Beware the potential risks of catching fewer winks. A 2019 Penn State study found that middle-aged adults with high blood pressure or diabetes who averaged less than six hours a night had twice the risk of dying from heart disease or stroke than those who dozed longer. People with a history of heart disease or stroke had three times the increased risk of dying from cancer if they clocked less than six hours a night. Examine your attitude towards lying awake at night Advertisement If you lie awake at night, don't fret. Van de Laar said awake time is normal — it's only a problem if you're restless or anxious. 4 Van de Laar said awake time is normal — it's only a problem if you're restless or anxious. Syda Productions – 'We have forgotten to lie awake because, in industrialized countries, we are faced with higher sleep pressure due to shorter bed time,' he said. 'In a more natural situation, where even the best sleeper lies awake a lot (such as the Hadza tribe in Tanzania), lying awake takes on a different and less problematic form.' Discover your personal sleep needs Van de Laar suggests experimenting with how much time you spend in bed to figure out what feels most restorative. 'If you find yourself regularly awake and restless in the night, institute a shorter bed time to increase sleep pressure,' he said. 'The goal at first is not to sleep better, but to have shorter periods of restless wake. This is how you break the negative circle of insomnia.' 4 The amount of time spent in bed can influence sleep quality. amenic181 – Advertisement To do this, estimate how long you slept on an average night last week and add half an hour. That's how much time you should spend in bed this week. Don't go under five hours. On the flip side, you should consider extending the amount of time you spend in bed if you sleep fairly continuously but feel like you are getting too little sleep. 'If you continue to have restful nights and function better during the day or even feel less sleepy, you know you are on the right track,' he explained. Respect your circadian rhythm Advertisement Circadian rhythm is your body's 24-hour clock — it regulates sleep-wake cycles, hormone release, appetite, digestion and body temperature. These natural processes are heavily influenced by light and darkness. 'Skip the 6 a.m. exercise class if it does not fit with your natural circadian rhythm,' van de Laar advised. 'Try to find out what your biologically determined day-night rhythm is, and try to follow it as much as possible.'
