A groundbreaking study published in Science suggests genetics may determine up to 55% of human lifespan, more than double previous estimates. Researchers analyzed Scandinavian twin data and found that while death rates remain steady between ages 20-40, they increase dramatically with age due to internal factors like aging and genetics. External causes like accidents and disease also rise with age but at a slower pace.

Lead researcher Ben Shenhar from the Weizmann Institute discovered this while developing a mathematical model of aging. The study indicates that genes influence disease risk differently - dementia is most heritable, followed by cardiovascular disease, then cancer. However, experts emphasize that hundreds or thousands of genes collectively influence lifespan, not just one or two. The remaining 45% of lifespan is attributed to environmental factors including lifestyle choices, healthcare access, and random genetic modifications.

Despite the genetic influence, health professionals stress that lifestyle choices remain critically important. Dr. Leonard Egede notes that poor lifestyle is still a major driver of morbidity and mortality, with healthy diet, exercise, stress management, and avoiding smoking being key modifications. Dr. Janet O'Mahony adds that regular medical care for conditions like high blood pressure and cancer screening can save lives. While genes lay the foundation, experts agree that lifestyle choices significantly impact healthspan and quality of life.