71. Live to be 180 years old
From POPULAR MECHANICS magazine
Live To Be 180
Biologists have cracked the secret of long life, but you might not want to pay the price.
BY JIM WILSON
Illustration by Frank and Jeff Lavaty/Yuan Lee
Published on: September 14, 2004
Thin Genes: Those who live longest tend to be naturally skinny.
This is the ultimate good news story. Your odds of living to be older than 100 just got better, as many as 80 years better. In the United States, census statistics reveal that centenarians have become the fasting-growing population group. Not surprising, most people who celebrate 3-digit birthdays have relatives who have lived to be older than 100. If long life doesn't run in your family, you will be happy to learn that researchers at the Massachusetts Institute of Technology (MIT) believe it is possible to chemically erase the difference between the genetic haves and have-nots.
HOW MANY CANDLES?
No one can calculate how long an individual human can live. We do know there is a biological limit, which falls somewhere between 120 and 180 years. The explanation has to do with fragments of DNA called telomeres. They extend human life in much the same way endcaps extend the life of shoelaces. The cells that make up the human body reproduce by splitting in half, a process called mitosis. When this occurs, cells make copies of the genetic material in their chromosomes. One copy goes to each new cell. Each chromosome has a protective cap that makes sure the information is successfully passed to the new cells.
Over time, the instructions contained in the chromosomes become damaged, similar to the way letters like "e" and "o" become distorted if a document is photocopied too many times. Cells run out of telomeres just before chromosomes become badly corrupted. Without telomeres, genetic instructions become too jumbled for cells to reproduce. By measuring the weight of telomeres and the rate at which cells divide, scientists have calculated the maximum theoretical human life span: somewhere between 120 and 180 years.
THE FAT CONNECTION
When 115-year-old Maud Farris-Luse died in Michigan in March 2002, headlines proclaimed her the world's oldest woman. MIT Biology Professor Leonard Guarente and his colleagues think they understand how she and other centenarians achieved their milestones. Long-lived people tend to be skinny people.
Beginning in the 1950s, biologists made a curious observation about yeast, worms and lab rats. Those who lived on the edge of starvation lived longer than their well-fed peers.
In June, Frédéric Picard, a biologist in Guarente's lab, published a solution to the starvation-longevity mystery in the science journal Nature. Predictably, the answer is genetic--specifically, it's tied to the gene that tells your body what to do with fat.
When you eat a hamburger you are digesting a combination of proteins, carbohydrates and fats. Humans and other mammals immediately convert the proteins and carbohydrates into energy. The body tucks away the fat for a rainy day, storing it in white adipose tissue (WAT) cells. If the body's minimum energy requirements cannot be met by metabolizing proteins and carbohydrates, it begins drawing on its stores of fat. The MIT discovery is that a single protein, Sirt1, controls the body's ability to store fat in WAT cells.
Researchers believe this mechanism evolved to enable humans to survive famines. To get Sirt1 to tell the body to shed rather than store fat, Guarente estimates, humans would have to cut their food consumption dramatically, to between 1000 and 1200 calories a day. "It would be like eating every other day," he says.
The payoff would be a longer life span--as much as a 50 percent increase, according to studies with rats and other lab animals with which humans share similar genes. But as the existence of the multibillion-dollar weight-loss and diet-book industry suggests, the price of calorie counting is higher than most people are willing to pay. Beyond causing chronic hunger, near-starvation diets kill the sex drive.
ULTIMATE DIET PILL
Guarente sees a less painful way to achieve the longevity-promoting ef-fects of a starvation diet. "If we could make a drug that would bind to Sirt1 and fool the body into thinking it needed to release fat, then maybe people could get the benefits of calorie restriction without the side effects," he says. To this end, Guarente has formed a company, Elixir Pharmaceuticals, that may someday bring this type of fat-blocking, life-prolonging drug to market. Will a single pill enable you to get maximum mileage from your telomeres while dining on a steady diet of cheeseburgers and supersize fries? Check back with us in 180 years.
Live To Be 180
Biologists have cracked the secret of long life, but you might not want to pay the price.
BY JIM WILSON
Illustration by Frank and Jeff Lavaty/Yuan Lee
Published on: September 14, 2004
Thin Genes: Those who live longest tend to be naturally skinny.
This is the ultimate good news story. Your odds of living to be older than 100 just got better, as many as 80 years better. In the United States, census statistics reveal that centenarians have become the fasting-growing population group. Not surprising, most people who celebrate 3-digit birthdays have relatives who have lived to be older than 100. If long life doesn't run in your family, you will be happy to learn that researchers at the Massachusetts Institute of Technology (MIT) believe it is possible to chemically erase the difference between the genetic haves and have-nots.
HOW MANY CANDLES?
No one can calculate how long an individual human can live. We do know there is a biological limit, which falls somewhere between 120 and 180 years. The explanation has to do with fragments of DNA called telomeres. They extend human life in much the same way endcaps extend the life of shoelaces. The cells that make up the human body reproduce by splitting in half, a process called mitosis. When this occurs, cells make copies of the genetic material in their chromosomes. One copy goes to each new cell. Each chromosome has a protective cap that makes sure the information is successfully passed to the new cells.
Over time, the instructions contained in the chromosomes become damaged, similar to the way letters like "e" and "o" become distorted if a document is photocopied too many times. Cells run out of telomeres just before chromosomes become badly corrupted. Without telomeres, genetic instructions become too jumbled for cells to reproduce. By measuring the weight of telomeres and the rate at which cells divide, scientists have calculated the maximum theoretical human life span: somewhere between 120 and 180 years.
THE FAT CONNECTION
When 115-year-old Maud Farris-Luse died in Michigan in March 2002, headlines proclaimed her the world's oldest woman. MIT Biology Professor Leonard Guarente and his colleagues think they understand how she and other centenarians achieved their milestones. Long-lived people tend to be skinny people.
Beginning in the 1950s, biologists made a curious observation about yeast, worms and lab rats. Those who lived on the edge of starvation lived longer than their well-fed peers.
In June, Frédéric Picard, a biologist in Guarente's lab, published a solution to the starvation-longevity mystery in the science journal Nature. Predictably, the answer is genetic--specifically, it's tied to the gene that tells your body what to do with fat.
When you eat a hamburger you are digesting a combination of proteins, carbohydrates and fats. Humans and other mammals immediately convert the proteins and carbohydrates into energy. The body tucks away the fat for a rainy day, storing it in white adipose tissue (WAT) cells. If the body's minimum energy requirements cannot be met by metabolizing proteins and carbohydrates, it begins drawing on its stores of fat. The MIT discovery is that a single protein, Sirt1, controls the body's ability to store fat in WAT cells.
Researchers believe this mechanism evolved to enable humans to survive famines. To get Sirt1 to tell the body to shed rather than store fat, Guarente estimates, humans would have to cut their food consumption dramatically, to between 1000 and 1200 calories a day. "It would be like eating every other day," he says.
The payoff would be a longer life span--as much as a 50 percent increase, according to studies with rats and other lab animals with which humans share similar genes. But as the existence of the multibillion-dollar weight-loss and diet-book industry suggests, the price of calorie counting is higher than most people are willing to pay. Beyond causing chronic hunger, near-starvation diets kill the sex drive.
ULTIMATE DIET PILL
Guarente sees a less painful way to achieve the longevity-promoting ef-fects of a starvation diet. "If we could make a drug that would bind to Sirt1 and fool the body into thinking it needed to release fat, then maybe people could get the benefits of calorie restriction without the side effects," he says. To this end, Guarente has formed a company, Elixir Pharmaceuticals, that may someday bring this type of fat-blocking, life-prolonging drug to market. Will a single pill enable you to get maximum mileage from your telomeres while dining on a steady diet of cheeseburgers and supersize fries? Check back with us in 180 years.
posted by Ross at 10:08 pm
2 Comments:
Gen 6:3 And the LORD said, My spirit shall not always strive with man, for that he also [is] flesh: yet his days shall be an hundred and twenty years.
..hope God can get his striving with me over and done with earlier than 180 years .... I am not sure I want to endure the great weariness for that long. If I can achieve the required state of harmony and love and can leave this scene early .... that would be nice. ....... unless of course I could be useful in some way, living those extra years. But I have had no such unction yet to half-starve myself to that end!
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