Josh Mitteldorf Science blog – a recent study of vitamin D supplementation reduced all-cause mortality rates by 6%. How many years would that add to life expectancy? A 6% increase of a 75-year life span would mean 4½ extra years. However, mortality increases with age. A 6% drop in mortality only increases life expectancy by 7 months.
To add just 5 years to life expectancy, we would need to slash the mortality rate by more than 40%. This is a counter-intuitive statistic – and a discouraging one. By optimistic accounts, taking a daily aspirin or ibuprofen lowers mortality by 13%. But even this major drop translates to only 2 years. From another perspective, 2 years is a windfall. Aspirin costs practically nothing and imposes minimal risk and less inconvenience.
There is another perspective on the “wall of death”, about which advocates of life extension have written compellingly. In medical research, we are working piecemeal to chip away at the mortality rate from one disease and another. But if the fundamental rate of aging can be slowed, this will push the curve not down but to the right. This will have as much benefit as many decades of progress in cancer and heart disease.
Caloric restriction offers a bit of this. CR mimetics, therapies that focus on gene expression and signaling may offer a health dividend comparable to the collective product of all of 20th century medical science.
The SENS anti-aging approach is to repair the accumalated damage from aging processes. This also has the potential for larger improvements in lifespan.