David A. Sinclair Quotes

Even if they don't recognize its violence, children come to understand the tragedy of death surprisingly early in their lives. By the age of four or five, they know that death occurs and is irreversible.2 It is a shocking thought for them, a nightmare that is real. A "GOOD, LONG LIFE." My grandmother "Vera" sheltered Jews in World War II, lived in primitive New Guinea, and was removed from Bondi Beach for wearing a bikini. The end of her life was hard to watch. "This is just the way it goes," she said. But the person she truly was had been dead many years at that point. At first, because it's calming, most children prefer to think that there are certain groups of people who are protected from death: parents, teachers, and themselves. Between 5 and 7, however, all children come to understand the universality of death. Every family member will die. Every pet. Every plant. Everything they love. Themselves, too.

prompting the United States in 1935 to join about twenty other countries that had already instituted a social insurance program. Social Security made moral sense. It made mathematical sense, too. At that time, just over half of men who reached their 21st birthday would also reach their 65th, the year at which most could begin to collect a supplemental income. Those who reached age 65 could count on about thirteen more years of life.32 And there were a lot of younger workers paying into the system to support that short retirement; at that time only about 7 percent of Americans were over the age of 65. As the economy began to boom again in the wake of World War II, there were forty-one workers paying into the system for every beneficiary. Those are the numbers that supported the system when its first beneficiary, a legal secretary from Vermont named Ida May Fuller, began collecting her checks. Fuller had worked for three years under Social Security and paid $24.75 into the system. She lived to the age of 100 and by the time of her death in 1975 had collected $22,888.92. At that point, the poverty rate among seniors had fallen to 15 percent, and it has continued to fall ever since, owing largely to social insurance.33 Now about three-quarters of Americans who reach the age of 21 also see 65. And changes to the laws that govern the US social insurance safety net have prompted many to retire — and begin collecting — earlier than that. New benefits have been added over the years. Of course, people are living longer, too; individuals who make it to the age of 65 can count on about twenty more years of life.34 And as just about every social insurance doomsdayer can tell you, the ratio of workers to beneficiaries is an unsustainable three to one.

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 the resulting decline in sirtuin activity, is thought to be a primary reason our bodies develop diseases when we are old but not when we are young. Trading reproduction for repair, the sirtuins order our bodies to "buckle down" in times of stress and protect us against the major diseases of aging: diabetes and heart disease, Alzheimer's disease and osteoporosis, even cancer. They mute the chronic, overactive inflammation that drives diseases such as atherosclerosis, metabolic disorders, ulcerative colitis, arthritis, and asthma. They prevent cell death and boost mitochondria, the power packs of the cell. They go to battle with muscle wasting, osteoporosis, and macular degeneration. In studies on mice, activating the sirtuins can improve DNA repair, boost memory, increase exercise endurance, and help the mice stay thin, regardless of what they eat. These are not wild guesses as to their power; scientists have established all of this in peer-reviewed studies published in journals such as Nature, Cell, and Science.

A new scientific truth does not triumph by convincing its opponents and making them see the light, Planck wrote shortly before his death in 1947, but rather because its opponents eventually die, and a new generation grows up that is familiar with it.