Have you ever wondered why some people appear younger than others, even though they are the same age?
Or why some animals live much longer than others?
There are insects that live only one day, and other species, such as turtles or whales, that can live up to 200 years.
There is no single answer to these questions, as there are many interrelated factors that condition life expectancy. External factors that contribute to the production of stress, diet, weather, pollution, and internal factors such as genetics, stress.
However, there is one important variable that is largely unknown by non-scientists: telomeres.
What are telomeres and what are their functions
Telomeres are the end of the chromosomes and resemble “caps”. They serve several purposes such as protecting our DNA and preventing our chromosomes from “fraying” or “sticking” to each other.
With each cellular division the telomeres length is decreased until it reaches the limit at which the cell can no longer undergo mitosis.
The consensus was that longer telomeres were an indicator of greater longevity; however, this is only partially correct. While it is true that telomere length at an intraspecies level indicates longer (or shorter) life expectancy which is corroborated by several studies on a variety of species including us humans.
While the length of the telomere is paramount so is the rate at which our telomeres shorten. This shortening, like telomere length, varies greatly between species, this difference has been preserved throughout evolution.
Humans lose about 70 base pairs per year – which are the building blocks that make up DNA – while mice lose 7,000 base pairs. This means that, even if a species has very long telomeres, they will not live long if their telomeric shortening rate is fast; however, a species with long telomeres and a slower shortening rate will have a much longer life expectancy.
Prior to these discoveries, it was also believed that size and weight were directly related to life expectancy, and not surprisingly, we often see how smaller animals live less time, although this rule does not always hold true, as there are species of similar sizes that have varying life expectancies, which has led scientists to discard this hypothesis and look for other explanations for this phenomenon.
Stress, nutrition and environmental factors
As we have mentioned, external factors have direct effects on aging and, therefore, on telomeres. There are multiple studies that relate telomere shortening to factors such as stress, diet quality or the environment.
In adverse circumstances, the rate of telomeric shortening and aging accelerates. All these factors can trigger evolutionary pressures at a genetic level and, although much remains to be discovered in this field, their direct effect is visible just by having a look at how life expectancy has evolved in both humans and other animals.
Let us remember that although there are differences between individuals of the same species, telomere length is dictated at birth. Life expectancy in humans has increased enormously since the invention of modern medicine and with successive improvements in living conditions, nutrition, and hygiene. As a curious fact, since the mid-1800s, life expectancy has increased by 3 months every year.
This means that our telomeres are prepared for us to live around 100 years depending on the living conditions and circumstances that each one of us has.
A clear example of how living conditions affect longevity can be seen in captive animals. They live longer than animals in the wild because their living conditions are less harsh as they have access to certain resources on a more regular basis as well as veterinary treatment.
Can telomeres be lengthened? Can we reduce their rate of shortening?
Unfortunately, there are currently no techniques that can lengthen telomeres in an effective and controlled manner, although research is being carried out in gene therapy with telomerase (the enzyme responsible for lengthening telomeres) for serious diseases caused by telomere irregularities such as idiopathic pulmonary fibrosis or cancer.
In the case of cancer, telomerase is one of the main culprits in its development, problems with this enzyme produces uncontrolled cell division that ends up generating what we all know as tumors. However, and fortunately for all of us, we can reduce the rate at which telomeres shorten through a series of anti-aging measures and by incorporating healthy habits. If you want to find out more, check out this article about telomerase and gene therapy.
How can I measure my real age and reduce the rate of telomere shortening?
Life Length offers our HealthTAV® service with its unique and patented TAT® technology that allows us to measure the length of our telomeres with a simple blood sample. Through this assay, we are able to analyze the state of your telomeres compared to an extensive data base comprising thousands of individuals and specifically in your age range and see if your biological age is older or younger than your chronological age. Additionally, we can advise you on how to adopt healthy life-style habits and other techniques that can contribute to reducing your rate of aging and contribute to an extended life span and optimal health.