Normal ageing is associated with diverse physiological changes in all organ systems but the rate and extent of these changes vary markedly among individuals. One aspect of ageing research focuses on the molecular profiling of the changes that occur with increasing age in humans. Such profiling has implications for disease prevention and treatment. New high-throughput 'omics' technologies (such as genomics, metabolomics, metagenomics and transcriptomics) are enabling detailed studies of these molecular changes and are thus revealing information about the biological pathways that change with age.