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Inside the center or nucleus of a cell, our genes are located. They reside on twisted, double-stranded molecules of DNA called chromosomes. At the ends of the chromosomes are stretches of DNA called telomeres (tell-o-mears), which protect our genetic data, make it possible for cells to divide, and hold some secrets to how we age and get cancer.
Picture your DNA as two shoe laces that are twisted together. Telomeres are like the plastic tips on the shoelaces. They prevent chromosome ends from fraying and sticking to each other, which would scramble an organism's genetic information to cause cancer, other diseases or death.
Yet, each time a cell divides, the telomeres get shorter.  When they get too short, the cell no longer can divide and becomes inactive or "senescent" or dies. This process is associated with aging, cancer and a higher risk of death. So telomeres also have been compared with a bomb fuse. This is why I preach to my "Cleanse Graduates" (and to my patients at the Center for Nutrition and Wellness that by living a "Genetically Congruent Lifestyle" you will actually decrease the number of times that your cells need to replicate, and therefore lengthen your life.
So just what are these telomere things anyway?
Like the rest of a chromosome and its genes, telomeres are sequences of DNA - chains of chemical code. Like other DNA, they are made of four nucleic acid bases: G for guanine, A for adenine, T for thymine and C for cytosine.
In human blood cells, the length of telomeres ranges from 8,000 base pairs of DNA at birth to 3,000 base pairs as people age and as low as 1,500 in elderly people. (An entire chromosome has about 150 million base pairs.) Each time a cell divides, an average person loses 30 to 200 base pairs of DNA from the ends of that cell's telomeres.
Cells normally can divide only about 50 to 70 times, with telomeres getting progressively shorter until the cells become senescent, die or sustain genetic damage that can cause cancer.
Telomeres do not shorten with age in some very specific tissues such as heart muscle in which cells do not continually divide.
Now let's discuss just why chromosomes have telomeres?
Without telomeres, the main part of the chromosome - the part containing genes essential for life - would get shorter each time a cell divides. So telomeres allow cells to divide without losing genes. Cell division is needed so we can grow new skin, blood, bone and other cells when needed.
Without telomeres, chromosome ends could fuse together and degrade the cell's genetic blueprint, making the cell malfunction, become cancerous or die. Because broken DNA is dangerous, a cell has the ability to sense and repair chromosome damage. Without telomeres, the ends of chromosomes would look like broken DNA, sort of like a "frayed end of a shoe lace. In that case the cell would try to fix something that wasn't broken. That also would make the cells stop dividing and eventually die.
Why do our telomeres then get shorter each time a cell divides?
Well before a cell can divide, the chromosomes within it are duplicated so that each of the two new cells contains identical genetic material. A chromosome's two strands of DNA must unwind and separate. When each new matching strand is completed, it is a bit shorter than the original strand. It is like someone who paints himself into a corner and cannot paint the corner.
Now the "Big Question" that you should have is; "Does anything counteract telomere shortening?"
Well take heart because you possess an enzyme named telomerase which adds bases to the ends of telomeres. In young cells, telomerase keeps telomeres from wearing down too much. But as cells divide repeatedly, there is not enough telomerase, so the telomeres grow shorter and the cells age.
Telomerase remains active in sperm and eggs, which are passed from one generation to the next. If reproductive cells did not have telomerase to maintain the length of their telomeres, any organism with such cells soon would go extinct.
I mentioned cancer at the outset of this article, so I need to discuss now the role that telomeres play in the onset and progression of cancer.
As a cell begins to become cancerous, it divides more often, and its telomeres become very short. If its telomeres get too short, the cell may die. It can escape this fate by becoming a cancer cell and activating the enzyme we just discussed called telomerase, which as I mentioned prevents the telomeres from getting even shorter.
Studies have found shortened telomeres in many cancers, including pancreatic, bone, prostate, bladder, lung, kidney, and head and neck.
Measuring telomerase may be a new way to detect cancer. In one experiment, researchers blocked telomerase activity in human breast and prostate cancer cells growing in the laboratory, prompting the tumor cells to die. But there are risks. Blocking telomerase could impair fertility, wound healing, and production of blood cells and immune system cells.
Once again I must interject right here that your "Eat Right, Think Right, Move Right and Sleep Right" are critical relative to your overall Health and Wellness and your longevity. Living a "Genetically Congruent" lifestyle is critical to not only reducing cellular replication, but as a result of this you will actually be extending your longevity.
So what proof is there that telomeres can actually affect the aging process?
Geneticist Richard Cawthon and colleagues at the University of Utah found shorter telomeres are associated with shorter lives. Among people older than 60, those with shorter telomeres were three times more likely to die from heart disease and eight times more likely to die from infectious disease.
But the telomere research doesn't actually define whether the proverbial cart or the horse is first. In other words while telomere shortening has been linked to the aging process, it is not yet known whether shorter telomeres are just a sign of aging - like gray hair - or actually contribute to aging.
If the enzyme "telomerase" makes cancer cells "immortal", could it prevent normal cells from aging? Could we extend lifespan by preserving or restoring the length of telomeres with telomerase? If so, does that raise a risk the telomerase also will cause cancer?
Scientists are not yet sure. But they have been able to use telomerase to make human cells keep dividing far beyond their normal limit in laboratory experiments, and the cells do not become cancerous.
If telomerase could be used routinely to "immortalize" human cells, it would be theoretically possible to mass produce any human cell for transplantation, including insulin-producing cells to cure diabetes patients, muscle cells for muscular dystrophy, cartilage cells for people with certain kinds of arthritis, and skin cells for people with severe burns and wounds. Remember as I tell all of my patients at Upper Perk Chiropractic Center , "the replacement parts are never as good as the originals!"
What about the role that telomeres play in the aging process?
Some long-lived species like humans have telomeres that are much shorter than species like mice, which live only a few years. Nobody yet knows why. But it's evidence that while telomeres may influence longevity they may not be the sole factor that dictates lifespan.
Cawthon's study found that when people are divided into two groups based on telomere lengths, the half with longer telomeres lives five years longer than those with shorter telomeres. That suggests lifespan could be increased five years by increasing the length of telomeres in people with shorter ones.
People with longer telomeres still experience telomere shortening as they age. How many years might be added to our lifespan by completely stopping telomere shortening? Cawthon believes 10 years and perhaps 30 years.
Once a person is older than 60, their risk of death doubles with every eight years of age. So a 68-year-old has twice the chance of dying within a year compared with a 60-year-old. Cawthon's study found that differences in telomere length accounted for only 4 percent of that difference. And while intuition tells us older people have a higher risk of death, only another 6 percent is due purely to chronological age. When telomere length, chronological age and gender are combined (women live longer than men), those factors account for 37 percent of the variation in the risk of dying over age 60. So what causes the other 63 percent?
A major cause of aging is "oxidative stress." It is the damage to DNA, proteins and lipids (fatty substances) caused by oxidants, which are highly reactive substances containing oxygen. These oxidants are produced normally when we breathe, and also result from inflammation, infection and consumption of alcohol and cigarettes (one "Hugantic" NO NO for our Silver Inner Health Circle tm. members, and the alcohol consumption better be red wine or dark beer and in moderation.). In one study, scientists exposed worms to two substances that neutralize oxidants, and the worms' lifespan increased an average 44 percent.
So, what's good for worms is good for us. Therefore I want all of you to eat dirt??? No, I was just checking to see if you were all still with me out there. What I want you to eat is what comes out of the dirt, meaning plenty of good wholesome Health producing, anti-oxidant rich vegetables and fruits!!! As our Cleanse Graduates (once again link to our Cleanse Graduates piece) know from their wonderful experiences with our Full System Detox Cleanse they not only felt better but they were decreasing the inflammatory load in their bodies, and reducing the rate and amount of oxidation in their bodies as well.
Another factor in aging is "glycation." It happens when glucose sugar from what we eat binds to some of our DNA, proteins and lipids, leaving them unable to do their jobs. The problem becomes worse as we get older, causing body tissues to malfunction, resulting in disease and death. This may explain why studies in various laboratory animals indicate that restricting calorie intake extends lifespan. As I discussed with our Cleansers as well as with my patients at the Center, you want to eat not only Health producing foods, but also Healthy quantities of that food. Not "filling" yourself, but rather "satisfying" yourself. That is an important distinction. You must work at understanding when you are satisfied, and not filling yourself up. This usually required that you eat more slowly and chew your food more completely. This will help. You also must listen to your body, so that you know when you are feeling "satisfied".
It is possible oxidative stress, glycation, telomere shortening and chronological age - along with various genes - all work together to cause aging.
What are the prospects for human immortality?
Human lifespan has increased considerably since the 1600s, when the average lifespan was 30 years. By 1998, the average U.S. life expectancy was 76. The reasons included sewers and other sanitation measures, hygeine, clean water, refrigeration, and other pre and post –natal efforts to reduce infant mortality, improved diets and better early detection of disorders.
Some scientists believe average life expectancy will continue to increase. Although many recognize that the average life-span should exceed 100 years, at this time most doubt the average will exceed 90.
Cawthon says that if all processes of aging could be eliminated and oxidative stress damage could be repaired, "one estimate is people could live 1,000 years."
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