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December 11, 2024 - February 3, 2025
Mental focus is a skill that you can cultivate. All it takes is practice. You’ll see a shoelace icon, pictured here, throughout the book.
you might use it as a cue to pause and ask yourself what you’re thinking.
And if you are not “doing” anything at all, then you can enjoy focusing on “being.”
Simply focus on your breath, bringing all of your awareness to this simple action of breathing in and out. It is restorative to focus your mind inside (noticing sensations, your rhythmic breathing), or outside (noticing the sights and sounds around you). This ability to focus on your breath, or your present experience, turns out to be very good for the cells of your body.
These renewing cells, which are called proliferative cells, live in places like your: immune system gut bones lungs liver skin hair follicles pancreas cardiovascular system lining heart’s smooth muscle cells brain, in parts including the hippocampus (a learning and memory center of the brain)
For these crucial body tissues to stay healthy, their cells need to keep renewing. Your
even though a body tissue can look the s...
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When cells can no longer renew themselves, the body tissues they supply will start to age and function poorly.
Having a good supply of stem cells that are able to renew themselves is key to staying healthy and to recovering from sickness and injury.
The cell can no longer renew itself. It becomes old; it becomes senescent.
Their internal powerhouses, the mitochondria, don’t work properly, causing a kind of energy crisis.
senescent cells send out false alarms in the form of proinflammatory substances, reaching other parts of the body as well.
While the underlying process of aging is similar in most of the cells that have been studied, a cell’s way of expressing that aging process can create different kinds of injury to the body.
Aging can be defined as the cell’s “progressive functional impairment and reduced capacity to respond appropriately to environmental stimuli and injuries.” Aged cells can no longer respond to stresses normally, whether the stress is physical or psychological.
OUT WITH THE OLD, IN WITH THE NEW: REMOVING SENESCENT CELLS IN MICE REVERSES PREMATURE AGING
Taking out the senescent cells reversed many of the symptoms of premature aging.
Senescent cells control the aging process!
Age spots
Telomeres, as you’ll see, play at least a small role in how quickly you develop an aged appearance, and whether you become one of those people who “age well.”
The aged melanocytes lead to age spots but also paleness.
The UV rays from sun exposure can damage telomeres.
Skin cells, when protected from the sun, can withstand aging for a long time.
Osteoblast cells need healthy telomeres in order to keep dividing and replenishing themselves—and
When these stem cells’ telomeres wear down, the cells can’t replenish themselves fast enough to keep up with hair growth, and gray hair is a result.
Looking older is associated in small but worrisome ways with signs of poor physical health.
The observation that inflammation increases with age and is a cause of the diseases of aging is so important that scientists have a name for it: inflamm-aging. This is a persistent, low-grade inflammation that can accumulate with age.
If a cell has become senescent because it’s been wounded, it can send signals to neighboring immune cells and other cells with repair functions, to call in the squads that can get the healing process going.
The telomere is so preoccupied with protecting itself that even though the cell has called out for help, the telomere won’t let the help in.
This unremitting but futile signaling can have devastating consequences. Because now that cell becomes like the rotten apple in the barrel. It starts affecting all the tissues around it.
Short-term, acute inflammation brings healing to injured cells, but long-term inflammation interferes with the normal functioning of body tissues. For example, chronic inflammation can cause cells of the pancreas to malfunction and not regulate insulin production properly, setting the stage for diabetes. It can cause plaque on an artery wall to burst. It can cause the body’s immune response to turn on itself, so that it attacks its own tissues.
you’ve got to prevent chronic inflammation. And a big part of controlling inflammation means protecting your telomeres. Since cells with very short telomeres send out constant inflammatory signals, you need to keep those telomeres a healthy length.
When short telomeres tell cells to age prematurely, the endothelium can’t renew itself to make strong, smooth blood vessel linings.
cognitive slowing. It may be hard to put your finger on what exactly is different about these folks, but you’ll notice that they seem a little fuzzier, a little out of it, a little less focused, and less tuned in to normal social cues. They may take a few extra seconds to remember your name. This mental loss, more than anything else, is what makes us feel really, truly old.
are fascinated by a possible relationship between the lengths of our telomeres and the sharpness of our thinking. Can short telomeres predict dementia or Alzheimer’s disease?
their hippocampuses were smaller than those of people with longer telomeres.
It isn’t just the hippocampus that is smaller in people with short telomeres. So are other areas of the brain’s limbic system, including the amygdala and the temporal and parietal lobes.
The Dallas study suggests that short telomeres in the blood crudely indicate an aging brain. It is possible that cellular aging, perhaps just in the hippocampus or perhaps throughout the body, may underlie an important pathway of dementia.
Short telomeres may help cause Alzheimer’s directly.
This is not a big effect, but it demonstrates a causal relationship: telomeres are not just a marker for something else, or an epiphenomenon, but rather they are causing part of brain aging—putting us at greater risk for neurodegenerative disease processes.
If you want to keep your brain sharp, think about your telomeres. See notes at the back of this book for a research opportunity on brain aging.21
75 percent—would say that they feel younger than their age. Even as the years go by, and even as the date of birth on our driver’s license tells us that we are getting older, many of us still feel young.
Having a younger “felt age” is associated with more life satisfaction, personal growth, and social connections with others.23
Wishing and longing for youth is really the opposite of our major developmental task as we age, which is to accept ourselves as we are, even while working toward maintaining our mental and physical fitness.
stereotype embodiment, was identified by Becca Levy, a social psychologist at Yale University.
act differently from people who have a sunnier view of aging.
If you have a negative view of aging, you can make a conscious effort to counter it.
remind yourself of the positive side of aging:
emotionally complex
close relationships
shows that our daily emotional experience is actually enhanced with age. Typically, older people experience more positive emotions than negative ones in daily life.
