They have also evolved to require a molecule called nicotinamide adenine dinucleotide, or NAD. As we will see later, the loss of NAD as we age, and t… - David A. Sinclair

The first principle is that you must not fool yourself — and you are the easiest person to fool." R. P. Feynman,

Bill Gates made a convincing argument for why improving human health is money well spent, and won't lead to overpopulation, in his 2018 video "Does Saving More Lives Lead to Overpopulation?"56 The short answer is: No.
If we were to stop all deaths — every single one around the globe — right now, we would add about 150,000 people to our planet each day. That would be 55 million people each year. That might sound like a lot, but it would be less than a single percentage point. At that rate, we would add a billion people to our ranks every eighteen years, which is still considerably slower than the rate at which the last few billion people have come along and easily countered by the global decline in family sizes.
It's still an increase, but it's not the sort of exponential growth many people fret about when they first encounter the idea of slowing aging.
Recall, these calculations are what we'd face if we ended all deaths right away. And although I'm very optimistic about the prospects for prolonged vitality, I'm not that optimistic. I don't know any reputable scientist who is.

THE THREE MAIN LONGEVITY PATHWAYS, mTOR, AMPK, AND SIRTUINS, EVOLVED TO PROTECT THE BODY DURING TIMES OF ADVERSITY BY ACTIVATING SURVIVAL MECHANISMS. When they are activated, either by low-calorie or low-amino-acid diets, or by exercise, organisms become healthier, disease resistant, and longer lived. Molecules that tweak these pathways, such as rapamycin, metformin, resveratrol, and NAD boosters, can mimic the benefits of low-calorie diets and exercise and extend the lifespan of diverse organisms.