**Telomere Length and Its Relation to Human Health**

Vivian F. S. Kahl and Juliana da Silva

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/64713

#### **Abstract**

Telomeres are complex nucleotide sequences that cap the end of chromosomes from degradation, unwanted recombination‐fusion, inappropriate activation of DNA damage response and play a critical role in cell division and chromosome stability. There is growing evidence that telomere stability can be affected by occupational and environmental exposure, as some of these factors have been correlated with increase in inflammation, oxidative stress, DNA damage, chromosome aberration, and epigenetic alterations. Both extremely short and long telomeres have been associated with neurodegenerative, cardiovascular diseases (CVD) and cancer risk. Occupational and environmental exposure to several synthetic and natural chemicals has been found to be associated with changes in telomere length, although the molecular mechanism is not fully understood. Telomeric DNA is relatively less capable of repair, resulting in accelerated shortening during the cell cycle and replicative senescence. It is recog‐ nized that diet plays an important role in telomere maintenance. Prevention of exposure to environmental and occupational hazards as well as psychological stressors can reduce the risk of telomere instability. This review provides a broad evaluation of the associated mechanism between human health and environmental and occupational exposure with telomere length, including recent findings and future perspectives.

**Keywords:** telomere length, biomarkers, human health, occupational exposure, envi‐ ronmental exposure
