Telomeres are long, repetitive sequences of DNA at the tips of our chromosomes to protect them from harm during cellular division. Every time a cell divides, the telomere shortens. When the telomeres are exhausted, cellular division stops and the cell dies. Telomere erosion is a central driver of illness and aging. As our telomeres shorten, our whole body deteriorates, leading to a range of aging-related diseases, such as heart disease, diabetes, Alzheimer's disease, and dementia. This book explains the many facets of human aging and shows you how to intervene in the aging process through lifestyle changes that boost the activity of the enzyme telomerase that lengthens your telomeres.