We now know that there are nine changes that happen to your cells as you age. Collectively, these changes result in structural damage and functional decline, which over time can manifest as the signs of aging and to age related health conditions.
One of these Nine Hallmarks of Aging is telomere shortening. So, what are telomeres and why are they important to the way you age?
DNA
To understand what a telomere is and why it is important, it is useful to understand a little about your DNA structure and function in the body.
Your DNA is inherited from your parents and provides instructions which tells your cells how to grow, function and reproduce. DNA is arranged into two chains which coil around each other to form a double helix.
Genes are made up of sections of DNA, which control how particular physical traits and characteristics are expressed in the body. Genes are housed in chromosomes, which are found in almost every cell of your body, except red blood cells, mature hair, skin, and nail cells.
Chromosomes
You probably are aware that humans have 23 pairs of chromosomes. Chromosomes are thread like structures, that neatly package your DNA into a structure found in each cell. The DNA double helix is tightly wrapped and organised around histone proteins and packaged into each of the 23 chromosome pairs found in your cells.
Your cells continue to divide and replicate throughout your life, from the moment you are conceived. This is needed to grow, develop, and replace body tissue, such as skin, that is continuously renewing.
Each time your cells divide, the chromosomes are copied and replicated to form the DNA for the newly created cell. This is where telomeres become important. The body has limitations when copying DNA strands, the structure is copied from one end of the chromosome strand to the other. As it nears completion, there is always a small section that cannot be replicated. Without telomeres, your chromosomes would become damaged, as the ends would fray and become damaged.
Telomeres
Telomeres are structures designed to protect the end of your chromosomes, similar to the caps found at the end of shoelaces. Each time your chromosomes are replicated, telomeres shorten in length. Without telomeres, the end of your chromosomes and, therefore your DNA, would be easily damaged. Therefore, telomeres are required for replication to occur.
Chromosomes are unable to replicate indefinitely, as eventually telomeres shorten to the point that replication can no longer take place. At this stage, telomere shortening, or telomere attrition, becomes one of the reasons that you age.
What can we do to protect telomeres?
There are strategies for protecting telomeres and the science continues to evolve. You can try to maintain telomere length or build telomere length.
Maintaining telomere length involves reducing the damage caused to this important structure. A healthy lifestyle including a wholefoods diet and regular movement have been shown to protect telomere health. Whereas, processed foods, saturated fats, high sugar intake, smoking and a sedentary lifestyle have been shown to be detrimental¹. Meditation has been shown to improve telomere length².
Enzymes are proteins involved in chemical reactions in your body. Telomerase is an enzyme involved in building and restoring telomere length. There is a lot of research studying how telomerase can be stimulated to reduce the damage caused as you age.
Supplements can provide your body with the nutrients to support healthy telomere length:
- Astragalus membranaceous (Astragalus) is a traditional Chinese herb that has been used to support healthy aging for hundreds of years. Recent research has found that a chemical component found in Astragalus stimulates telomerase activity³.
- Selenium and Zinc have been shown to maintain telomere length by protecting telomeres against oxidative stress⁴,⁵.
- Vitamin D has been shown to reduce telomere shortening⁶.
Suzy Walsh
BBA (Hons)., BNat., mNMHNZ
Registered Naturopath & Medical Herbalist
References:
¹ Balan, E., Decottignies, A., & Deldicque, L. (2018). Physical activity and nutrition: Two promising strategies for telomere maintenance? Nutrients, 10(12), 1942. doi: 10.3390/nu10121942
² Conklin, Q. A., King, B. G., Zanesco, A. P., Lin, J., Hamidi, A. B., Pokorny, J. J., Álvarez-López, M. J., Cosín-Tomás, M., Huang, C., Kaliman, P., Epel, E. S., & Saron, C. D. (2018). Insight meditation and telomere biology: The effects of intensive retreat and the moderating role of personality. Brain, Behavior, and Immunity, 70, 233-245. doi: 10.1016/j.bbi.2018.03.003
³ Guinobert, I.,et al. (2020). The use of natural agents to counteract telomere shortening: Effects of a multi-component extract of astragalus mongholicus Bunge and Danazol. Biomedicines, 8(2), 31. doi: 10.3390/biomedicines8020031
⁴ Shu, Y., Wu, M., Yang, S., Wang, Y., & Li, H. (2020). Association of dietary selenium intake with telomere length in middle-aged and older adults. Clinical Nutrition, 39(10), 3086-3091. doi: 10.1016/j.clnu.2020.01.014
⁵ Sharif, R. (2012). Zinc and genomic stability (Doctoral dissertation, University of Adelaide, Adelaide, Australia). Retrieved from https://digital.library.adelaide.edu.au/dspace/bitstream/2440/85982/8/02whole.pdf
⁶ Zarei, M., Zarezadeh, M., Hamedi Kalajahi, F., & Javanbakht, M. (2020). The relationship between vitamin D and telomere/Telomerase: A comprehensive review. Journal of Frailty & Aging, 1-8. doi: 10.14283/jfa.2020.33