Another research program should be to upregulate cancer suppression. For example, gene therapy to create additional copies of p53 should be studied. I believe that cancer is the primary mechanism of human aging. People die with heart disease and neurodegeneration, but they die of cancer, as is case with mice. Research programs should in general focus on upregulating immune function to suppress cancer.
The rate of aging is exponential
We do not age for the same reason cars wear out. Unlike cars, our bodies have the ability to repair themselves. There is no reason our bodies cannot repair themselves indefinitely. There is no reason why an old body cannot be stronger and healthier than a young body. Aging and death are not inevitable. Many organisms do not age, and significant progress has already been made in extending the healthspans of many more.
Most evidence points to the fact that aging is an adaptation to the environment. This is rejected since it implies group selection, which has been discredited. However, theoretical rejections of group selection are in my opinion not well founded. Furthermore, group selection is the best explanation for the programmed self destruction in cicadas, octopuses, Pacific salmon, sepsis, and in the explanation of eusocial animals.
Some of an organism's characteristics are adaptations to the environment, some of its characteristics are irrelevant to evolutionary survival, and some are maladaptations that have not yet killed the species. The longer period of time that a trait is evolutionarily conserved, the less likely it is that the trait is a maladaptation. The same genes that affect longevity in worms affect longevity in flies and mice and whales and elephants. Thus, aging is heavily evolutionarily conserved. Furthermore, we know that aging is indeed relevant to evolutionary survival as changes in temperature, resources, and fertility have drastic affects on lifespans in worms and flies. Thus, the rate of aging adapts to the environment.