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Restricting calories may extend life for normal-weight people, according to a new study that sought to measure the pace of aging in people asked to cut their calorie intake by 25% over two years. there is.
“We’ve known for nearly 100 years that calorie restriction can extend healthy lifespan in a variety of laboratory animals,” says senior author Daniel Bell, associate professor of epidemiology at Columbia University’s Mailman School of Public Health. Ski said.
“This is done by altering biology in ways consistent with slowing down the aging process, but the specific mechanisms of how this happens are still under investigation,” said Belsky, who studies longevity. “We decided to drill down to the cellular level of humans to see if the same was true.”
of The study used what is commonly known as the “biological clock” to determine the pace of aging. its participants.Bioclock is designed to measure age People compared to biological Their real ages in chronological order.
“Our study finds evidence that caloric restriction slows the pace of aging in humans,” said co-lead author Robert N. Butler, co-scientist at the Columbia Aging Center in Columbia. said Karen Ryan of
“Our findings are important because they provide evidence from a randomized trial that it may be possible to slow aging in humans,” Ryan said in a statement.
However, longevity scientist Dr. Peter Attia dismissed the findings as “noise.”
“We see no evidence that any of the biological clocks are meaningful,” Attia, who was not involved in the study, said in an email. I host a podcast, The Drive, dedicated to doing.
“The only test of significance, to my knowledge, has not been done, but I hope it will be, whether ‘biological age’ is a better predictor of future life than chronological age. to make sure,’ he said.
Biological age predictors are controversial, says calorie restriction researcher Professor Pankaj Kapahi. Buck Institute on Aging, Novato, California.
“At best, it tells us something about very small aspects of aging,” said Kapahi, who was not involved in the study. “For example, grip strength is also a predictor of biological age.” , how active is also a predictor: we know anyone who is physically crumbling but their cognitive abilities are all there, so cognitive aging should also be tested.
“Some researchers are trying to boil it down with bioaging tests,” he added. I don’t think it’s an exaggeration to say that.”
Decades of animal research have shown that calorie restriction produces health benefits and can even slow the pace of aging.
1950s research We asked people to reduce their calories by 50%. participant.Subsequent research Often the focus is on calorie reduction in people whose BMI is considered medically obese.
In 2007, the first clinical trials of caloric restriction began in people of normal weight (BMI around 20-25). Curry Leeor an overall assessment of the long-term effects of reduced energy intake.
Because malnutrition was found In previous studies CALERIE asked 143 adults between the ages of 21 and 50 to reduce their normal calorie intake by 25% over a two-year period. Another group of 75 people maintained a normal diet as a control group.
A full range of tests were performed at six-month intervals during the study to collect information on weight loss, changes in resting metabolic rate, effects on cognitive function, inflammatory markers, cardiovascular health, and insulin sensitivity. I got
As a result of CALERIE, Published in 2015found that, on average, people in the restricted group were able to cut 14% of their calories, or about half of their 25% goal. , reduced fat mass by about 10% and reduced cardiometabolic risk factors, researchers said. was seen
Many other studies have used blood samples and other data collected in CALERIE participants to investigate other ways that moderate calorie restriction may benefit the body. , Researcher at Yale University It has been found that restricting calories increases the health of the thymus, an organ that produces immune system T cells, one of the body’s primary warriors against invaders.
new research, Published Thursday in Nature Aging, sorted DNA sequences from leukocytes collected at 12-month intervals from CALERIE participants.Belsky’s team then analyzed the methylation marks — a sign of epigenetic changes. — Look for signs of aging in your DNA.
Epigenes are proteins or chemicals that exist like freckles on each gene, waiting to tell the gene what to do, where and when. According to the National Human Genome Institute.
“Increasingly, changes in our cell’s epigenome, the system that controls which genes in the genome are turned on and off, are being recognized as drivers of the aging process,” said the Bravatnik Institute at Harvard Medical School. Co-Director of the Paul F. Glenn Center for the Biology of Aging Research.
“The clocks that measure these changes have proven to be indicators of future health, and show what interventions may slow or reverse the aging process.” said Sinclair, who was not involved in the study.
In a new study, researchers used two epigenetic clocks. — PhenoAge and GrimAge — and new tools that Belsky recently invented in collaboration with Duke University.This his third bio clock called Dunedin PoAm, Belsky says he’s trying to determine the pace of aging with a single blood test.
PhenoAge and the Grimage bioclock showed no signs of reduced aging in blood samples from CALERIE participants, Belsky said. Columbia University’s Robert N. Butler Aging Center.
However, DunedinPoAm, a watch created by Belsky and Duke’s team, found that the pace of aging decreased by 2% to 3%. smoking cessation intervention According to a Colombian statement.
But critics of the study were unimpressed. DunedinPoAm test performance was “mediocre at best” and weakly related to biological aging, Attia said.
The fact that two other biological clocks did not find anti-aging benefits is not surprising, says the Buck Institute. Kapahi: “These biological age predictors are not consistent with each other and not necessarily with other biological measures.
“It will confuse the public. Unfortunately, people are buying these tests when there is little useful information to be gained from them.”
Admittedly, epigenetic biomarkers are not yet ready for use in clinical trials, but “many different studies in many different data sets and populations show how these algorithms can help people get sick and live.” It shows that it predicts the difference between people who die,” Belsky countered.
“This is not a game over moment. It’s more like a game.” Belsky said. “What we have now is a proof of concept: people who are known to be at higher risk of disease, disability and death age faster, and people who are known to be at lower risk age slower. It is a methylation biomarker that indicates
Aside from the debate about how slower aging is measured, Attia said there is a role for caloric restriction in extending lifespan, especially in “overnourished” individuals.
“I don’t want readers to think that this intervention (calorie restriction) has no value, just that[the study]has not ‘proved’ a reduction in the pace of aging,” he said in an email. Stated.
Time-restricted meals and restricted diets of specific foods are two additional ways to curb “overnutrition,” which Attia believes is the biggest contributor to insulin resistance. Type 2 diabetes and other chronic diseases.
“I am not aware of any evidence that any one ‘strategy’ or method is superior. “The best ones are the ones that work for people, but caloric restriction certainly works for some people, so it’s clearly beneficial,” Attia said. It will lead to a better life, but these aging clocks tell us less than zero about the process.”
Kapahi said there are many other ways to slow down aging.
“We are learning more about aging, but caloric restriction is just one intervention,” he said. “You’ll need to do it in combination with exercise, good sleep, a positive attitude, and mental health. All of this combined could play a bigger role in slowing down aging.”
