As the global population ages, the risk of age-related diseases and disabilities increases, posing a growing burden on healthcare systems worldwide. Rather than treating each disease as it arises, scientists are exploring a more efficient approach: tackling aging itself—the root cause of many chronic conditions.
Dr. Tony Wyss-Coray, a leading researcher in brain aging at Stanford University, compares aging to the wear and tear on a car. “You get it off the lot and it’s all shiny, and everything works perfectly. As you keep driving it over the years, all the parts look older,” he explains. “Exposure to the elements and usage lead to a growing level of wear and tear, ultimately resulting in dysfunction.” Similarly, as we age, the cells and molecules in our bodies accumulate damage, and the body’s repair mechanisms become less effective, leading to the decline of vital organs and systems.
Understanding the science of aging at a molecular level has become a priority for researchers funded by the National Institutes of Health (NIH). By studying the ways aging impacts our bodies, scientists are hoping to discover methods to slow, or even reverse, this process. The goal is not only to extend life but to improve quality of life by delaying the onset of age-related diseases like cancer, heart disease, and dementia.
Measuring Biological Age: A New Frontier
One of the most promising areas of aging research involves measuring biological age, which reflects the molecular damage that accumulates over time. While chronological age is the number of years someone has lived, biological age varies from person to person and can be used to predict how likely someone is to develop age-related diseases.
Dr. Daniel Belsky of Columbia Mailman School of Public Health explains that measuring biomarkers allows scientists to assess someone’s biological age. For instance, if 50-year-old’s biomarkers resemble those typical of a 55-year-old, they are considered biologically older. Using tools like “aging clocks,” researchers can track how individuals age and predict their risk for various diseases.
Belsky and his colleagues have developed an innovative “aging speedometer” called DunedinPACE (Dunedin Pace of Aging Calculated from the Epigenome). This tool uses DNA methylation patterns to measure how quickly someone is aging. It helps determine whether someone is aging faster or slower than expected, and could guide healthcare providers in making earlier decisions about screenings or preventive measures.
Reversing Brain Aging: A Glimmer of Hope
Among the most concerning effects of aging is its impact on the brain. As we age, our ability to learn and remember decreases, often due to a loss of synaptic plasticity—the ability of neurons to strengthen their connections. This process is critical for cognitive function, particularly in the hippocampus, the region of the brain involved in learning and memory.
In a groundbreaking study, Dr. Wyss-Coray’s team showed that injecting aged mice with young mice’s blood improved synaptic plasticity and cognitive function. They identified a protein called TIMP2, found in the blood of young mice, as a key factor in restoring brain function. These findings suggest that factors in young blood may be able to reverse some aspects of brain aging, offering hope for future treatments for neurodegenerative diseases like Alzheimer’s.
Calorie Restriction: A Simple Yet Powerful Intervention
While age-reversing therapies are still in the distant future, researchers agree on the importance of lifestyle interventions to slow aging today. Dr. Belsky points out that physical activity, healthy eating, and avoiding harmful behaviors like smoking can have a profound impact on slowing the aging process.
One of the most well-studied lifestyle interventions is calorie restriction (CR), where individuals reduce their caloric intake while maintaining adequate nutrition. Studies in animals have shown that CR can increase lifespan and delay age-related diseases, and recent human studies, such as the NIH-funded CALERIE study, are showing promising results.
Participants in the CALERIE study who reduced their caloric intake by 12.5% over two years exhibited slower biological aging as measured by biomarkers. They also saw improvements in muscle strength, despite a slight loss of muscle mass, suggesting that CR could help preserve muscle function with age.
Practical Tips for Healthy Aging
While the search for anti-aging treatments continues, experts like Dr. Luigi Ferrucci, director of NIH’s National Institute on Aging, emphasize that simple lifestyle changes can have a significant impact on aging. Regular physical activity, maintaining a healthy weight, not smoking, getting adequate sleep, and managing chronic conditions like hypertension are key to promoting longevity and reducing the risk of age-related diseases.
Dr. Ferrucci notes, “People have demonstrated that if you do these things, you can increase your life expectancy by 10 years. We don’t need a magic pill. The magic pill is already here.”
As research continues into the molecular underpinnings of aging, the hope is that these lifestyle changes, along with emerging treatments, can help delay the onset of age-related diseases and enhance the quality of life for older individuals around the world.