Genomic instability refers to alterations and DNA damage in the genome. This is usually prevented through DNA repair and maintenance processes. However, as individuals and cells age, repair processes become less effective resulting in more damage.

Telomeres are protective DNA caps at the ends of chromosomes. They shorten with each cell division, and once critically short, cells lose the ability to divide normally, often entering senescence or undergoing programmed cell death.

Epigenetic changes regulate which genes are “on” or “off” without altering DNA sequence. With age, shifts in DNA methylation, histone regulation, and non-coding RNAs can disrupt normal gene control and contribute to cellular dysfunction.

Proteostasis is the cell's ability to make, fold, and clear proteins correctly. With age, this quality-control system becomes less efficient, increasing misfolded or damaged proteins and impairing normal cellular function.

Macroautophagy is a cellular recycling process that delivers damaged components to lysosomes for breakdown. With age, reduced macroautophagy can allow dysfunctional proteins and organelles to accumulate inside cells.

Cells use nutrient-sensing pathways to adjust metabolism, repair, and growth to available fuel. With age, these signals can become dysregulated, contributing to metabolic imbalance and reduced cellular resilience.

Mitochondria produce much of the cell’s usable energy. With age, mitochondrial efficiency can decline due to damage, altered quality control, and reduced turnover, contributing to lower energy production and higher cellular stress.

Cellular senescence is a state where stressed or damaged cells stop dividing but remain metabolically active. Senescent cells accumulate with age and release inflammatory signals that may impair tissue function.

Stem cell number and function decline, reducing the body's capacity to renew tissues and recover from injury.

Aging disrupts hormonal and molecular signals between cells, weakening coordination across tissues and organs.

Chronic inflammation is a persistent, low-grade inflammatory state. With age, inflammatory signalling often rises, which can damage tissues over time and accelerate age-related dysfunction.

Dysbiosis is an imbalance in the gut microbiome. With age, microbial composition and microbe–immune interactions can shift, promoting inflammation and affecting metabolic and immune function.