 We've talked broadly about the hallmarks of aging and even gone into them in more detail in individual videos. The hallmarks have provided a useful framework for guiding and interpreting longevity research. Today, we want to talk about a proposed expansion, the social hallmarks of aging. Welcome to X10, your one-stop YouTube show for all things life extension. Learn the science, keep up with new research, and live longer and healthier. If you want to know when we release new episodes, subscribe, click the bell icon and select All Notifications. The social hallmarks of aging were proposed in a 2020 paper by Eileen Crimmins of the University of Southern California. Crimmins presents the social hallmarks as a set of underlying interrelated causes of age-related outcomes, similar to the way the biological hallmarks underlie different diseases and disorders of aging. Some people might be tempted to dismiss this by saying that the biology is more fundamental. If we can figure that out, we can ignore the social aspects. But Crimmins makes a convincing argument against that view. She doesn't just say that we should pay attention to social factors. She shows that social factors predict aging outcomes even when biological factors are taken into account. In other words, these social factors are drivers of aging in their own right, not just adjuncts to biological processes. Crimmins analyzed data from over 1100 participants in the Health and Retirement Study, a large nationally representative study of Americans over 56. Her analysis included several biological metrics, such as telomere length and epigenetic age, as well as the demographic factors age and sex, and five social metrics, socioeconomic status, adverse childhood experiences, adult trauma, negative psychological states, and poor health behaviors such as smoking or drinking. Crimmins built several models to test different combinations of these factors. All of them had the demographic factors, but the first model only added the social factors, the second only the biological factors, and the third included everything. The first two models each showed a strong link between the factors they included and the aging outcomes, which were multi-morbidity, disability, cognitive deficiency, and two-year mortality. The interesting result is the third model, which included both social and biological factors. This analysis showed that the social factors predicted much more of the variance in aging than the biological factors did. In other words, even when taking into account biological markers of aging, the social elements were still the strongest predictors. The biological factors weren't just telomere length and epigenetic age. Crimmins also included the difference between chronological age and biological age, as measured by 10 physiological markers. So a significant amount of the variance in aging isn't captured by these biological measures, but instead by social measures, the social hallmarks of aging. The five social factors that Crimmins used aren't necessarily THE social hallmarks of aging, but they seem to be a good start. More importantly, they demonstrate the value and strength of this approach. It might be that the social hallmarks would become irrelevant if we had a complete biological understanding of aging. Crimmins makes that very point in her paper, but she also says we have a long way to go before we'll get there. In the meantime, the social hallmarks can help guide longevity research. By capturing variability in aging that the biological markers miss, they can direct us towards sources of that variability. Working that out could uncover new biological factors linked with aging. A more important benefit of the social hallmarks of aging is that they help us identify things we can do right now to increase lifespan and health span. Addressing social factors that drive aging probably won't increase maximum lifespan, but would very likely boost the median lifespan. Understanding longevity in this framework provides us with therapeutic targets to improve the life, health, and lifespan of many people. The fact that these targets are social and organizational changes instead of pharmaceutical interventions doesn't make them any less valid or valuable. What do you think? How should the longevity community work towards these goals? Or should the focus stay purely on biology and biological interventions? Let us know in a comment. Remember to subscribe if you want to find out whenever we release a new video. Thanks again to the Lifespan Heroes whose contributions fund this work. If you want to help promote longevity research, consider making a pledge at lifespan.io slash hero.