On Saturday, May 17, the Bay Area community gathered for Health Matters, Stanford Medicine’s free annual community health event. Held outdoors on the medical school campus, the event attracted more than 1,250 attendees who participated in live health talks and explored interactive exhibits at a health pavilion staffed by professionals from Stanford Medicine and Stanford Health Care.

During the three health talks, Stanford Medicine physician-scientists addressed a full-capacity audience, sharing their latest research and practical tips for improving longevity through healthy habits, precision medicine’s ability to diagnose and treat patients faster and more accurately, and insights into the origins of mental health disorders.

Nearly 900 people tuned in via livestream from around the world.

Healthy longevity

Thanks to advances in health care and medicine, a century-long lifespan is becoming a reality for more people than ever before. “People are not just thinking about living longer; they’re thinking about living healthier,” said Deborah Kado, MD, MS, a professor of medicine–primary care and population health.

Kado dispelled common misconceptions about aging, particularly related to what it truly means to grow older. “There is a belief that to be old is to be sick,” she said. “Many people believe that chronological age is a standard marker of a person’s expected decline through their life course. As a practicing geriatrician, I believe you should not use chronological age as a metric of how someone should be expected to do.”

Research has shown that most people aged 85 and older live independently and do not report any health-related limitations. While adults aged 65 and older represent 18% of the population in the United States, only 4% of that group reside in nursing homes.

Although we cannot control our genetics or disabilities, Kado believes we can manage many factors that positively impact our health at any age. She explained that maximizing longevity relies on a combination of factors: prioritizing meaningful social relationships, engaging in regular exercise, ensuring adequate sleep, and maintaining a nutritious diet.

Above all, Kado emphasized that aging is as much a matter of mindset as it is a biological change. “In a study of individuals with a genetic predisposition to developing Alzheimer’s disease, those who held a positive attitude about aging at 30 years old had a 50% reduced likelihood of developing Alzheimer’s disease 50 years later,” she noted.

“Age doesn’t define you; how you live does. It’s a cognitive choice,” she said. “Think about your attitudes toward aging and your self-expectations. If you figure out what matters to you, you can make a difference in your life.”

The future of medicine, precisely

In the second talk of the day, Euan Ashley, MB ChB, DPhil, chair of the Department of Medicine and a professor of genetics and of biomedical data science, discussed the transformative potential of precision medicine in health care.

Ashley, who is the Arthur L. Bloomfield Professor of Medicine and the Roger and Joelle Burnell Professor of Genomics and Precision Health, emphasized the importance of genetic information in shaping human health.

“Inside every single one of you is a secret code,” Ashley said. “This code has been defining you since the moment you were conceived and will continue to define you until the moment you pass.”

The secret code he referred to is the human genome, represented by 6 billion individual letters. It was first decoded in the year 2000 at a cost of $3 billion. Today, thanks to technological advancements, genome sequencing costs an average of $100, making it significantly more accessible to more people.

Ashley explained that having access to a patient’s genetic code provides invaluable information for physicians and scientists in diagnosing and treating diseases. “Precision medicine is understanding disease at a molecular level,” he explained.

Precision medicine can help those who suddenly become ill, but also those who spend years living without a diagnosis. Through the Undiagnosed Diseases Network, Ashley and a global team of doctors are leveraging genomics to tackle complex medical cases using their principal tool—the human genome.

Recalling a real-life scenario of precision medicine’s abilities, Ashley recounted how he and his team broke the world record for sequencing a human genome in 11.25 hours for a young patient in heart failure. They were able to make a diagnosis within days of the patient’s arrival at Stanford, and the patient received a heart transplant 21 days later. The standard test, which Ashley also performed, did not come back until three weeks after the patient received their transplant.

Tying into Ashley’s work in cardiovascular disease, he also pointed out the importance of exercise. “One of the most potent interventions for your health is exercise,” he said. “One minute of exercise will buy you five minutes of extra life.

“It reduces the risk of cardiovascular disease, high blood pressure, diabetes, multiple cancers, anxiety, and depression,” he added. “We have no pill that is as potent.”

The intelligence behind emotions

In the day's final talk, practicing psychiatrist and leading neuroscience researcher Karl Deisseroth, MD, PhD, the D.H. Chen Professor and a professor of bioengineering and of psychiatry and behavioral sciences, shed new light on how our biological history is shaping current scientific breakthroughs.

“I came to Stanford as an MD/PhD student 30 years ago, studying how neurons work. In a lab just a few feet from here, we were taking single electrodes [and] poking single cells in petri dishes,” Deisseroth stated, opening his talk. “Flash forward to now: Electrophysiology of human brains—guided by decades of work in animal models—is just now starting to come together.”

The essence of the connection between then and now is a common theme in Deisseroth’s work. “A lot of the tools we’re using now come from ancient molecules and structures,” he said. “Billions of years ago, the oceans were full of single-celled organisms. These cells got energy from light with the help of ancient proteins.”

At Stanford, Deisseroth applied this ancient approach of harvesting light for energy to study and manipulate the complex electrical activity of the brain. “What we’ve been able to do at Stanford is to use this ancient approach, to bring these proteins, which are billions of years old, and put them into the brain to turn light into electricity and control neurons with light. This is what we call optogenetics,” Deisseroth explained.

These light-activated proteins can activate neurons in the brain for precise control of brain activity. With a flash of light, scientists can turn up or down inhibitory or excitatory cells, and can see what happens to an animal's behavior, cognition, memory, and motivation. This is a way of understanding the causal role of cells in complex brain function.

Not limited to the brain, optogenetics has played a larger role in understanding the body’s connection to emotions. Deisseroth placed an ancient light-activated protein in the heart of a mouse to pace it at any speed. He established a link between increased heart rate and heightened anxiety, cementing the connection between the body’s physiological states and emotions. “You need the body, you need the manifestations of the body, for the full expression of emotion to be felt,” Deisseroth explained.

Through Deisseroth’s discovery of optogenetics, scientists can stimulate individual cells to study how cognition, action, behavior, perception, and motivation arise from the activity or inactivity of controlled cells. This science has helped cure a form of blindness and holds promise across all domains of psychiatry.

“If you can find which cells cause anxiety, hopelessness, mania, for instance, we could design medications to target those cells,” Deisseroth said. “Understanding is the most important thing.”

Watch the health talks here.