Is aging an incurable disease? Or can aging be treated?<\/p>\n\n\n\n
Scientists are moving to the idea that aging is not, in fact, an inevitable doom that we’ve so far believed it to be. Rather, aging is a treatable disease. Biologist David Sinclair suggests a number of different ways to treat aging, either by delaying the symptoms or (in some cases) actually reversing the damage.<\/p>\n\n\n\n
Here’s how to reverse aging, according to David Sinclair. <\/p>\n\n\n\n\n\n\n\n
According to biologist David Sinclair, aging is a disease<\/a> that can be treated, and we are slowly but surely getting there. In his book Lifespan<\/em>, he discusses how to reverse aging and extend both lifespan and healthspan. <\/p>\n\n\n\n Sinclair says that we can prolong our own life and health through hormesis:<\/em> A phenomenon by which our bodies become stronger in response to stressors like hunger, extreme temperatures, and physical damage. Hormesis activates numerous survival mechanisms, such as conserving resources and repairing cellular damage. Sinclair believes we can take advantage of hormesis not just to extend our lives, but to improve our quality of life as well.<\/strong><\/p>\n\n\n\n We already employ hormesis in several ways, such as dieting, exercising, and sitting in saunas. However, Sinclair says that recent and upcoming scientific advancements will allow us to control these processes more effectively and efficiently\u2014for example, we might be able to use an injection to strengthen our muscles without the need for exercise. <\/p>\n\n\n\n (Shortform note: In Antifragile<\/em><\/a>, <\/em>Nassim Nicholas Taleb<\/a> tells us that the toxicologist Hugo Schulz first discovered hormesis when he noted that small doses of particular toxins would actually cause yeast cells to grow and reproduce more quickly<\/a>\u2014though higher doses would kill the yeast as expected. From this, we can see that hormesis has limits; the key is to use mild <\/em>stressors, like hunger, instead of severe stressors like starvation.)<\/p>\n\n\n\n Sinclair recommends intermittent fasting (IF) as a way to trigger your body\u2019s stress responses without causing malnutrition. He suggests several different variations of IF, saying that it\u2019s currently unclear which method is best, but all are beneficial:<\/p>\n\n\n\n Sinclair also says that a vegetarian diet can activate hormesis. The relatively low levels of certain proteins (as compared with meat) can trigger our survival mechanisms in the same way that calorie restriction does. <\/p>\n\n\n\n (Shortform note: In addition to triggering hormesis, vegetarian diets tend to be relatively low in fat, sodium, sugar, and cholesterol compared to meat-heavy diets. Scientists believe that a vegetarian diet reduces the chance of heart disease, cancer, and diabetes<\/a>, lowers blood pressure, and strengthens bones.) <\/p>\n\n\n\n Finally, Sinclair says that exercise (which, by definition, puts stress on our bodies) can greatly extend our lifespans. For example, researchers have found that exercise lengthens and protects telomeres. Telomeres <\/em>are small complexes of DNA and proteins at the ends of our chromosomes that get shorter each time a cell divides. When the telomere runs out, the cell stops dividing\u2014leading to many of the problems of old age. Therefore, lengthening telomeres can literally keep our bodies younger for longer. <\/p>\n\n\n\n Sinclair adds that exercising in low temperatures appears to boost the youthening effects of exercise, most likely due to combining the stress of working out with the stress of being exposed to cold.<\/p>\n\n\n\n (Shortform note: It doesn\u2019t take a lot of exercise to significantly improve your health<\/a>. Researchers found that 150 minutes (two and a half hours) of moderate exercise each week increased life expectancy by about seven years<\/a>, and that active 70-year-olds had hearts, lungs, and muscles that were as strong as some 40-year-olds\u2019.)<\/p>\n\n\n\n As we get older, our cells start to shut down, which causes a lot of the deterioration that we experience as we age. Sinclair believes that destroying those cells before they cause too much damage can significantly extend both life and health. <\/p>\n\n\n\n Cells that are no longer able to divide<\/strong>, or that suffer genetic or epigenetic damage too severe to repair, can enter senescence<\/em>: They don\u2019t function anymore, but they also don\u2019t die when they should<\/strong> (leading some researchers to refer to them as \u201czombie cells\u201d).<\/em> <\/em><\/strong>Furthermore, senescent cells can cause other <\/em>cells to enter senescence, so the process only accelerates once it\u2019s begun. <\/p>\n\n\n\n Sinclair says that senescent cells send out chemicals that cause inflammation in surrounding tissue, which is associated with symptoms of aging. Therefore, it seems likely that senescent cells are responsible for many of the negative effects of old age. <\/p>\n\n\n\n Researchers found that destroying senescent cells in mice extended their remaining lifespans by a third or more and reversed many of the effects of aging; in theory, the same principle should apply to humans.<\/strong> To that end, researchers began testing senolytics <\/em>(\u201csenescence destroyers\u201d) on people in 2018, though Sinclair says it could be years before we have any conclusive results about their effectiveness and safety for human patients.<\/p>\n\n\n\n While the focus of Sinclair\u2019s work is undoing the damage caused by aging, he also believes that technology will extend our years of health by letting us recognize and treat diseases before the symptoms even begin.<\/strong> Improved DNA sequencing techniques will allow us to find genetic markers and risk factors for numerous conditions, while biometric devices (like smartwatches) can track our vital signs and warn us of potential problems. Furthermore, Sinclair believes that having access to this detailed information will allow experts to design diets, exercise programs, and treatment regimens that are custom-tailored to your genetics and lifestyle. <\/p>\n\n\n\n (Shortform note: Sinclair\u2019s vision of using technology to prevent disease isn\u2019t hypothetical; geneticists can already use DNA analysis to determine if someone\u2019s at risk for cancer<\/a>, Parkinson\u2019s<\/a>, and numerous other diseases<\/a>. Also, when Sinclair says biometrics<\/em>, he <\/em>just means taking information about your vital signs<\/a> like heart rate and blood pressure. It\u2019s the same data that doctors collect in the medical office, so it\u2019s not unreasonable to imagine relying on wearable tech like smartwatches instead of visiting a doctor in person.)<\/p>\n\n\n\n Of course, sharing such intimate personal data comes with enormous privacy and security concerns. Sinclair says we\u2019ll each have to decide how much we\u2019re comfortable with sharing, but he personally believes it\u2019s more than worth the risk\u2014much like how our cell phones collect tons of data about us, but we still use them. In fact, Sinclair shares that he uses biometric devices himself, and that the insight he gains from them is worth the potential risks. <\/p>\n\n\n\n (Shortform note: While Sinclair is talking about using biometrics to track our vitals, biometric technology\u2014including tech that\u2019s already widely used\u2014encompasses a lot more than heart rate and blood pressure<\/a>. Biometric security devices can use everything from your fingerprints to the sound of your voice to determine that you are who you say you are. The main security risk with biometric data is that it can\u2019t be altered; <\/strong>if a hacker got your password you could simply change it, but if a criminal had your fingerprint, there would be no way to lock him out of the system while still allowing yourself to access it.)<\/p>\n\n\n\n On a less personal level, Sinclair says that improved technology such as new vaccines and 3D-printed organs\u2014which don\u2019t force you to wait and hope that a match becomes available\u2014will enable us to avoid diseases and recover from grievous injuries or surgeries more easily. <\/p>\n\n\n\n (Shortform note: Scientists are currently working on creating functional organs in a lab<\/a> using 3D-printing technology, but the process is still in its infancy. Experts say that we might be as much as 30 years away from the sort of organs-on-demand that Sinclair envisions.) <\/p>\n\n\n\n When it comes to repairing epigenetic damage, Sinclair\u2019s work focuses on sirtuins<\/em>\u2014enzymes that regulate the epigenome. He believes he can reverse many of the effects of aging by bolstering our sirtuins because they\u2019re involved in everything from repairing DNA to suppressing inflammation\u2014all of which they accomplish by activating or deactivating certain genes in response to certain stressors. <\/p>\n\n\n\n We\u2019ve already discussed Sinclair\u2019s theory that DNA damage doesn\u2019t directly cause aging. Now he adds that sirtuins have to move away from their usual functions in order to repair DNA damage. <\/strong>As we age and start suffering from more and more problems, this leads to two issues: First, the sirtuins aren\u2019t able to get back to their positions before they have to rush out to repair more damage. Second, sometimes they don\u2019t return to the correct positions. These two things lead to epigenetic chaos\u2014genes that should be active are deactivated, and vice versa. <\/p>\n\n\n\n Therefore, manipulating sirtuins to work more effectively\u2014which scientists have done in mice with drugs like resveratrol\u2014helps combat the effects of aging and extends life. The next step, Sinclair says, is to find drugs that cause the same effects in humans. <\/p>\n\n\n\n (Shortform note: Sirtuins are a relatively new area of study, and while initial research results look promising, there isn\u2019t yet much evidence that we can effectively manipulate them in humans or that we\u2019d get the desired results by doing so. A scientific review from 2020 summed up the results<\/a> of many different studies on sirtuins in organisms ranging from yeasts to primates. In short, it says that sirtuins are \u201cpromising targets\u201d for therapies to treat everything from age-related diseases to cancer, but there are still few (if any) studies using human subjects.) <\/p>\n\n\n\n Sinclair believes that the true cure for aging<\/a> may be a set of four genes, called Yamanaka factors<\/a>, that reverse aging in cells<\/strong>\u2014not just the effects <\/em>of aging, but aging itself. Shinya Yamanaka, the stem cell researcher who discovered these genes\u2019 potential, showed that they could cause adult cells in a petri dish to revert to immature stem cells. Those stem cells could then re-mature into young, healthy cells of any type.<\/p>\n\n\n\nTake Advantage of Hormesis<\/strong><\/h3>\n\n\n\n
Killing Senescent Cells to Preserve Other Cells<\/strong><\/h3>\n\n\n\n
Protecting Health With Technology<\/strong><\/h3>\n\n\n\n
Clearing Epigenetic \u201cNoise\u201d With Sirtuins<\/strong><\/h3>\n\n\n\n
Turning Back the Clock With Yamanaka Factors<\/strong><\/h3>\n\n\n\n