Nothing seems more inevitable than aging and death—not even taxes. Yet as we better understand the biological processes of aging, we’re realizing that aging may be a process that can be controlled.
Slowing down or stopping the aging process is more than just a crazy theory. Indeed, the clues have been there for decades. For example, while it may seem as if every animal and plant you have ever seen ages and dies, that is not true. Scientists have known for decades that many cold-water fish, amphibians, and the American lobster do not age or die natural deaths. Instead, they keep growing and remain youthful and capable of reproducing until something kills them—predators, disease, the elements, or an accident. Something in their genes protects them from aging.
Indeed, in the past decade, several genes have been identified that, when altered, can dramatically increase the lifespan of simple animals. For example, changing a few genes can allow a worm that is commonly used in scientific experiments (a worm called C. elegans) to live five times longer than usual. That’s the equivalent of a human being living 400 years.
The genes associated with longevity typically affect the body’s handling of sugar and calories. To aging specialists, this is not surprising. For 70 years, scientists have known that severely restricting caloric intake extends the lifespan of many animals. Would that work in humans? No one has ever shown it, and no one is likely to study it, because most people just couldn’t tolerate such calorie restriction, which would mean eating as few as 800 calories a day.
Scientists at MIT and Harvard have been studying whether it might be possible to achieve the life-extending effects of calorie restriction without restricting calories. What? Yes, that’s what I said. The scientists reasoned that calorie restriction probably works by turning on certain dormant genes, and found such aging-related genes—called sirtuin genes—in yeast and other simple animals.
Then the scientists went looking for chemicals that turned on the sirtuin genes just like calorie restriction does. They found one molecule, called resveratrol, that filled the bill. Resveratrol is a chemical found in grapes and red wine. Then they fed resveratrol to simple animals: yeast, fruit flies, worms, and fish. In each of these animals, resveratrol greatly extended their lifespan.
Then, they moved on to animals that are genetically more similar to humans—mice. They separated the mice into three groups. Group One was fed a regular diet. Group Two was fed a high-calorie, high-fat diet. Group Three was fed a high-calorie, high-fat diet plus resveratrol.
Group Two developed fatty livers, inflamed heart muscle, and a diabetes-like condition, and also died young, compared to the mice in Group One. In contrast, the mice in Group Three did not develop complications or die young from their high-calorie, high-fat diet: The resveratrol protected them.
These results are exciting because, like the mice in this study, many of us are middle-aged mammals on a high-calorie, high-fat diet. Not only that: All of us have sirtuin genes that are nearly identical to those of mice. However, not all exciting results in mice prove to be true in humans. We’ll need years of future study to know if these results extend to humans
You may well ask: Why would I want to take a medicine that extended my life? Why would I want to prolong my period of decrepitude? That’s a fair question, but it may not be relevant: In simpler animals the resveratrol has preserved the vitality of the animals during their added time alive. Take the worm, for example. The young worm wriggles around the dish it’s in, then slows down in the last third of its normal lifespan, and barely moves in the period leading up to its death. However, the worms whose lifespan is extended by resveratrol keep on wriggling till very near the end.
There would of course be huge social questions raised by any technology that was able to extend human lifespan on a planet that already is terribly overcrowded. At a minimum, technologies that add more people would need to be accompanied by technologies that dramatically decrease the cost of energy and food, and decrease the pollution that comes from expending energy. Otherwise, the problem of overpopulation would worsen. Yet, it is hard not be excited at the possibility that scientists may be closing in on ways to increase the number of our vital and productive years.
What are your thoughts on the possibility of living a drastically longer life? What problems do you foresee for society as a whole? What excitements can you imagine on a personal level?
Anthony Komaroff, M.D., is the Simcox-Clifford-Higby professor of medicine at Harvard Medical School (HMS), and editor-in-chief of Harvard Health Publications at HMS. He is a practicing senior physician and was formerly director of the Division of General Medicine at Brigham and Women's Hospital.
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Comments: 19
Or, will this be a situation where those that have get older and those that don't die young? Lest you consider this the raving of a leftist, I assure you that I am one of the most conservative members of Gather. The issue disturbs me deeply.
Society is not going to be the same as more and more elders survive. We are already living twice as long as the average person in 1907. We boomers were supposed to inherit more money than any generation in history, but our parents did not die when they were expected to. My mom is 73, has a new boyfriend, has a new house and goes out dancing every Friday night. That is how I want to live.
Resveratrol, I have never heard of this. Not that I am a member of any MD group, but I do read quite a bit. Thank you for this article, in regards to your question about the ramifications of living longer: well we are now seeing the problems associated with our aging population living longer.
"I think will do just fine".
The sad thing is the "well to do " will almost always live longer, because of their ability to access great health care and medications.
I read Dr. Nulander's book "How We Die", and I found it to be informative and fascinating. I learned a great deal about aging and dying
with the language written for a layperson such as my self. Thanks
I am also glad the health benefits of anti-oxidants, trace minerals, and mood-enhancers in dark chocolate confirm what I expected. I knew there was a reason I like it so much.
Blueberries have also had excellent press lately. I love those too.
Dr. Sears has very interesting information on regulating brain function and mood by eating protein and complex carbohydrates in certain ways and logging how it works for you. The point of doing this is to regulate energy so that you are sleepy when you need to be and energized when you need that.
Exercise also works on mood. So if eating in certain ways inclines people to move more, as described with the worms, then the benefits of exercise will be more available to those who choose to eat this way.
Exercise triggers healthful biochemicals of many kinds as well as improving the plumbing systems in the body in mechanical ways.
There are hopeful signs that changes are happening that will allow people to live in more sane ways. In Portland, there is a group called Growing Gardens that encourages less advantaged people to grow some of their own food. We have community gardens where you can get a plot. In Vancouver, B.C., street people are being organized to grow food in the back yards of people too busy to deal with their back yards.
If many of our necessities can be produced close to where we live, the complexity and expense of transporting things long distances can be reduced. This would reduce employment in long-haul trucking, but employment in other ways could increase.
A famous Japanese farmer, M. Fukuoka, has said there is enough land even in Japan for each individual to grow enough food on a quarter-acre to eat well. But growing his way, without chemicals, without tilling, is very labor intensive.
Labor and exercise are components of a healthful lifestyle. Research supports that depression goes up when unemployment does. I worked in social work for many years. I believe most people want to work, if work can be found that is constructive and appropriate to the abilities of the individual. I also believe most people understand the health risks of isolation and inactivity.
I am working with a group in low-income housing on health and wellness issues. These are detached homes, out from town in an area that was peripheral. Some grow some of their own food now, but mostly the grounds are maintained by contractors.
As it is, this property is probably coveted by developers and what will happen to the property in the long run involves politics I don't know about. What I can say now, though, is that landscaped with edibles, such as grapes, this property could look like the garden of Eden rather than sort of sad, same, and depressing as it looks now.
Fancy houses are going in all around, and one of the women in my group said, "Oh, they must not like it when they look over here." I doubt that is so, because people struggle to deal with their own issues, but I ponder how to help people with the morale challenges of feeling this way. Many of the people in this complex work, they just don't earn very much. Some are physically disabled or working to recover from illness.
Optimal health for the largest number of people involves reform on many fronts.
If it is true that oil will become much less available, then the value of growing necessities in small places without chemicals will go up.
Some of our cancers will go down as we are less exposed to toxins. Converting from centralized agriculture to back yard had to happen overnight in Cuba. The average Cuban lost between 20 and 30 pounds.
I had to scroll up to reel myself back in, though I am glad when I did that the challenges for society were part of the charge. As for excitement, I guess I am looking forward to the increased diversity of plants and animals we will have when we run out of oil. It is oil that now supports factory farms and monoculture. People are already preparing in this town of Portland.
People here are so jaded, they roll their eyes about bird flu, and tend to their chickens in the back yard. My friend has chickens in one of the fanciest neighborhoods in Portland. Some of her neighbors don't like it, but three chickens are allowed: it's in the code. Annually, there is a Tours de Coops--chickens are all over the place, as are people growing copious amounts of food in their back yards.
One M.D. I know has been composting humanure from his family for 15 years. He has a compost heap with a thermometer in his back yard. He insists this is legal, and a show about him has been produced on listener-supported radio.
If we have an earthquake and the sewers break (not entirely unlikely for Portland), he says there are people all over town who will be ready to show others how to safely do this. And then, he says, fewer of us will be eating food grown with sewage sludge and the icky stuff that gets in sewage sludge.
Thanks for the article.
As I said at the end of my blog, a technology that made human life longer could cause major problems in a world of limited resources. We would also need new technologies to make energy, food and water more accessible and affordable. In other words, I completely agree with your concerns. That's one of the reasons I wanted to talk about this potential new technology.
I agree with you that living longer is a wonderful thing to dream about--so long as we are vital and productive in those healthier years. As you point out, Nan, this already is happening to some extent: "60 is the new 40", people over 60 are as a group much healthier (as well as more numerous) than people over 60 were 30 years ago. But science is raising the possibility that this may happen even more dramatically in the coming years. If it does, we have to figure out how to provide the resources (energy, food and water) for those folks who live longer.
If this came to fruition, it would require a re-structuring of a large portion of our society. And, who's to say that every person who received the therapy would go on to a vital life - to say aged 200 or more? We can't know what random factors might affect a person, so there are no guarantees.
Personally, I'd like to be around a thousand years to see what will be...but only if I could be healthy, active, and vital.
Yes it would require major restructuring, but societies go through pretty major upheavals, in a fairly short time, and live to tell the tale. For example, humans have been on earth for a million years or more, but in just the last 100 years--the blink of an eye, in historical terms--society has changed dramatically in the United States.
At the turn of the 20th century, 95% of Americans worked on farms, raising their own food. Now we're mostly in cities and suburbs and most of us wouldn't know the first thing about growing a tomato, let alone a field of wheat. Most of us wouldn't know how to milk a cow, and surprisingly many do not know where the milk in the supermarket comes from. At the turn of the 20th century, practically no one even imagined human beings flying through the air, let alone to the moon.
And they surely never imagined that I would be able to sit in a hotel room in Europe, as I am doing right now, sending this comment to you through the air, to land instantaneously in your lap thousands of miles away.
Human beings are pretty good at dealing with change--even though we hate to think of changing anything.
P.S It may not help but I will icease my eating of grapes and add red wine to my diet....