Ageing is the gradual accumulation of molecular and cellular damage over time. This process leads to a decrease in physical and mental capacity and an increased risk of disease. While natural, the rate of ageing is variable and can be influenced by lifestyle interventions addressing biological drivers. Source: National Institutes of Health (.gov)
The Biological Hallmarks of Ageing
Scientists identify specific "hallmarks" that drive the ageing process at a cellular level:
Genomic Instability
DNA damage accumulates from external agents (radiation, chemicals) and internal errors, eventually overwhelming repair mechanisms.
Telomere Attrition
Chromosome ends (telomeres) shorten during cell division; once too short, cells stop functioning or die.
Cellular Senescence
"Zombie cells" stop dividing but don't die, secreting inflammatory factors that damage healthy tissue.
Mitochondrial Dysfunction
Cellular powerhouses become less efficient, reducing energy and increasing oxidative stress.
Epigenetic Alterations
Changes in gene expression (on/off switches) affect immune function and hormone levels.
Source: National Institutes of Health (.gov)
Functional Changes in the Body
Ageing reduces the body's "reserve capacity," affecting all major systems:
- Cardiovascular: Heart walls and arteries stiffen, forcing the heart to work harder to pump blood.
- Musculoskeletal: Bones lose density (osteoporosis) and muscle mass declines (sarcopenia), impacting balance.
- Cognitive: Processing speed may slow, impacting learning and memory recall.
- Digestive & Metabolic: Metabolism slows, and changes in the large intestine can lead to digestive issues.
Source: Mayo Clinic