Why is it that mice have a life expectancy of only 3 years, while bats can live for up to 20 years, elephants to 70 years, giant tortoises up to 150 years, red coral for as long as 500 years, and humans no more than about 120 years.
Scientists continue to seek out the secrets of longevity and what it is that results in a long life. Various factors such as diet, body weight and lifestyle have not fully answered questions about why it is that different animals and even humans have such differing lifespans. More recently, however, we have discovered that nature has placed within the genetic code of all living things a mysterious signal or command that determines our true life expectancy, and once we near the end of our lives, our bodies gradually begin to slow down, and prepare to stop working; various illnesses and ailments follow, and eventually we pass away.
Scientists have found that there are many genes or genetic codes associated with signalling the body’s cells to gradually stop working. The telomere is one of these important keys.
A telomere is a structure at the end of each strand of DNA. Within the DNA are molecules that contain our genetic code, and telomeres protect the DNA strands from deteriorating too soon. Simply put, telomeres are like the plastic tips at the end of shoelaces that protect and keep them from fraying and falling apart too quickly.
Dr Elizabeth Blackburn, winner of the Nobel Prize for her discoveries regarding the importance of the telomere and its effects on the human body, tells us that telomere length shortens with age. Simply put, the older we get, the shorter our telomeres become. However, how fast or slow our telomeres shorten differs from person to person, as it is dependent on factors related to our individual lifestyles, such as our diet and food choices; whether or not we exercise; our stress levels; whether or not we smoke or consume alcohol, and if so, how much; whether or not we get adequate sleep; as well as any toxins and various forms of radiation we may be exposed to. All of these factors can result in faster than usual telomere attrition or shortening.
Accelerated telomere shortening, or shorter than average telomere length for a specific age group, can cause us to contract illnesses at a faster rate and with higher incidence than normal. Additionally, shortened telomere has also been linked to various degenerative diseases, such as cancer, coronary artery disease, Alzheimer’s, diabetes, and many more.
Today, we are able to use a simple blood test that doesn’t require the patient to refrain from food and water ahead of time. This blood test can tell us how much our telomeres have deteriorated. Results are available within 10 days and, once we receive them, can help to tell us things about the appropriateness of our current lifestyle, and what lifestyle changes can be adopted to improve our current and future health. If our telomeres are exceptionally short, we know that we can more easily contract a variety of diseases; thus, we can make choices to prevent this. We ourselves can choose whether we want to be healthy or sick.
The telomere shortening mechanism ensures that the aging process happens correctly, and according to the laws of nature and the natural impermanence of the body.
This natural mechanism is also what helps our normal cells to function properly, and ensure they do not divide too rapidly. How slow or fast a person ages is dependent on more than one factor—half of this is hereditary, while the other half is due to our individual lifestyles. For this second half, therefore, we have the ability to use the power nature gives us by taking care of ourselves, and choosing to live our best life possible.
Master of Science in Clinical and Public Health Nutrition (Distinction). UCL Division of Medicine, London. , 2016