Seizing the Years with Derek Yach
Health isn’t just about avoiding disease. It’s about how we move, think, and find meaning in our lives. Few people understand this better than Derek Yach. As a physician, epidemiologist, and global health leader, he has spent decades shaping policies that impact millions. But his most profound insights come from his own journey, one marked by resilience, curiosity, and an unshakable commitment to staying active, even in the face of illness.
A three-time cancer survivor, Derek has defied expectations, swimming through chemotherapy, questioning standard medical advice, and exploring the role of nutrition, stress, and spirituality in healing. For him, health is more than just medicine, it’s about movement, mindset, and the moments that remind us why we fight to stay well.
I sat down with Derek to talk about the lessons he’s learned through illness, the power of cold water swimming, and why redefining health means looking far beyond the physical.
From Cape Town to Global Health
Derek: It’s great to be here, Rachael. My public health journey began in apartheid-era Cape Town. I was torn between medicine and law, but a mentor (Marian Jacobs, first Dean of UCT Medical School, an amazing woman and POC) steered me towards public health, saying I had a passion for change, not clinical empathy. She was right.
I moved into epidemiology, working across rural South Africa and launching the country's first birth cohort study when Mandela was released. This study has yielded insights into HIV/AIDS and social violence.
At WHO, I focused on making global policies work locally and led the creation of the first global tobacco treaty. I then worked in academia and the private sector, including PepsiCo and Vitality, always aiming to reshape industries and drive healthier choices through behavioral economics.
My career's common thread? Prevention is neglected. We need to make healthy living easier and more rewarding, not just advise people. The challenge is always turning knowledge into action.
My work at the Foundation for a Smoke-Free World faced boycotts, which is tragic. We have the science to end smoking, but we need courage to bridge the public and private sectors.
I've served on advisory boards for organizations like the Wellcome Trust and World Economic Forum, always focused on prevention, real-world application, and standing firm for change despite criticism.
Rachael: You’ve often found yourself in spaces where your ideas were met with resistance, yet you’ve been able to work across boundaries. Given today’s polarization, how do you see major organizations evolving to promote prevention and longevity over the next decade?
Derek: The highest levels of global health are at a turning point. Some organizations may not survive in their current form. UN agencies, especially WHO, face funding threats and resistance to public-private partnerships.
I saw this with the Framework Convention on Tobacco Control. When I asked Gro Harlem Brundtland if the UN would develop new health treaties, she said it was unlikely. The global landscape had shifted too much for major players to agree. She saw private-public partnerships as the way forward, despite their challenges.
Jimmy Carter’s river blindness initiative showed how well this can work. WHO, the World Bank, Merck, and academia collaborated to nearly eradicate the disease. That model needs to be used more if UN agencies want to stay relevant.
The World Economic Forum is a space for corporations to test ideas and influence change. I worked with them on longevity initiatives, including The Silvering of the Economy, which reframed aging as an economic opportunity.
When we talk about healthspan, the real concern is that while life expectancy is increasing, the number of healthy years is not. The U.S. has the biggest gap—people are spending their last 8-10 years in poor health. The real question is: How do we ensure people live long and reach 120 without disease or suffering?
This idea isn’t new. Jim Fries introduced it in 1980 as compression of morbidity—minimizing disease until the very end of life. The challenge is making that vision a reality.
Longevity Starts With The Basics
Derek: The path to longevity isn’t just about complex science; it starts with the basics. Staying active, eating well (with some modifications beyond the Mediterranean diet), and having a sense of community and purpose are crucial. Then, we layer in medical advancements such as vaccines, preventive medications, and even emerging drugs like Ozempic, which could play a role beyond diabetes.
The real question is: Who’s leading this charge? We’re seeing a mix, nonprofits in Saudi Arabia, the Wellcome Trust in the UK, and a pharmaceutical sector increasingly engaged. Longevity is becoming the next frontier for global health.
Rachael: It’s interesting that lifestyle comes first on your list, with medical interventions as a final layer. That’s a message we focus on, too; supplements and medications should support, not replace, a foundation of good habits.
Derek: Exactly. When I was at Vitality, we ran a fascinating study with 100,000 participants. A small incentive (something as simple as a free cup of coffee) was enough to get people to walk an extra 1,000 steps a day. But the real discovery? Once they achieved that small win, they were far more likely to take on bigger health challenges like weight management or quitting smoking.
This highlights an overlooked truth: change is incremental. You don’t start with the hardest habit. You start small, build confidence, and create momentum. If someone begins a medication but hasn’t tackled their lifestyle, the long-term impact will be limited. Success comes from combining interventions in the right order, making sustainable progress.
Rachael: That makes so much sense. We often talk about negative habits snowballing, with one unhealthy choice leading to another over the years. But the same principle applies in reverse: small, positive changes compound, building towards a healthier life. The pressure to make drastic, all-at-once transformations can actually backfire.
Shifting gears a bit, beyond global health policy, personal and social influences play a huge role in shaping our health. How important is family and early-life environment in setting those habits?
Derek: It’s a critical piece we don’t talk about enough. When WHO launched a major commission on childhood obesity, the focus was on taxes, regulations, and bans. But my colleague at Vitality, Adrian Gore, raised a key issue: why weren’t we discussing parenting?
The data is clear: when parents make healthy choices, eating well, staying active, not smoking, their children benefit. Yet, we shy away from emphasizing parental responsibility, fearing it’s too intrusive. The reality is that many parents today struggle with their own health (obesity, diabetes, smoking), so kids are sometimes the ones influencing them in a positive way.
But we’ve regressed. Social media has disrupted parent-child relationships, and without strong role models at home, it’s harder to instill healthy habits. If we want lasting change, we can’t ignore the influence of family dynamics.
Rachael: That really resonates. Especially with my background in childhood education psychology. The habits we form early shape everything that follows.
Derek: The simplest but most overlooked answer? Do things together. Eat together. Too many families are defaulting to takeout, eating separately, or scrolling through their phones at dinner. A book that stuck with me—Why French Women Don’t Get Fat—highlighted the power of communal meals. In France, meals are an event. Phones stay away, conversation happens, and food is enjoyed with intention. That’s something we’ve lost.
I’ll admit, even in my own family, getting everyone to put their phones down isn’t easy. But modeling behavior is key. Parents have to be the example, not just enforce the rules. Social media is becoming a major disruptor of real-life connection—addressing that will be one of the biggest challenges ahead.
Diving Into Open Water
Rachael: Speaking of habits, open-water swimming isn’t for everyone, but you’ve taken on some serious challenges. What’s your journey with that?
Derek: I don’t see it as a challenge; it’s just part of my life. It brings me joy. I started swimming at two or three in South Africa with my father, who swam for the country in the Helsinki Olympics. I competed and then got into lifesaving at Clifton Beach, one of the most beautiful places in the world. Back then, we’d swim miles offshore without thinking about sharks… until there was an attack. That made us a bit more cautious!
From there, I swam to Robben Island, then became the first person to do a round trip. Eventually, I tackled the English Channel. I was lucky with good weather, good tides, and a great support team. That led to other major swims, Capri-Naples, multiple crossings of the Hudson, and, most recently, a Lausanne-to-Evian swim across Lake Geneva.
The pandemic shifted things. The pools were closed, so we turned to open water. I live on Long Island Sound, which connects to the Atlantic but is somewhat protected. A small group of us (maybe 10 per beach) swim year-round, even in winter, without wetsuits. The community aspect is huge.
Wherever I travel, I find a place to swim: London’s Serpentine, Hampstead Ponds, Loch Ness in Scotland, and the heated waters of Abu Dhabi. Swimming isn’t just exercise for me; it’s a way to stay connected to my body, my mind, and the world around me.
Derek: Right now, our swims are shorter, but we're still out there, even when the water drops to three degrees. Next month, we’ve got the big Vermont swimming tournament at Lake Memphremagog. They actually cut a pool out of the frozen lake, and about 150 of us gather for three days of ice swimming.
People think we're crazy (and maybe we are!), but the joy on everyone’s faces tells a different story. Swimmers of every age, shape, and background come together, many overcoming significant health challenges. The cold doesn’t deter us; if anything, it heightens the experience.
For me, swimming has always been more than just an activity; it’s a daily ritual. Two things make it especially meaningful: swimming in a natural setting at sunrise and sharing that experience with others. Out there in the open water, life’s problems seem to fade away.
Rachael: That sounds incredible. We visited Buttermere, a small lake in the North of England, last summer and saw a group of women (mostly 65+) swimming in just their caps and goggles, laughing and having the time of their lives. Their joy was so pure, almost childlike.
Derek: The UK has truly embraced wild swimming. I read outdoor swimming magazines regularly, and the stories are inspiring—people swimming for mental health, for companionship, for resilience.
When I was recovering from surgery, I wasn’t sure if I’d ever swim again. I started with water aerobics at the YMCA, surrounded mostly by women in their 80s. It was humbling—I got a far tougher workout than expected! I saw people with severe mobility issues come to life in the water. That’s the beauty of it: water removes the strain of gravity, making movement possible when it otherwise wouldn’t be.
As we age, high-impact exercises like running become harder on the body. Swimming, on the other hand, supports longevity and overall health without the wear and tear.
Rachael: Absolutely. Water has always been healing across cultures and history.
A Journey Through Illness and Resilience
Rachael: Speaking of healing, you’ve faced some significant health battles. You’ve spent your life in public health, and yet, you’ve personally had to navigate some of the most challenging diagnoses. Would you be open to sharing that experience?
Derek: Of course. I’ve faced cancer three times. First, a melanoma more than a decade ago—treated successfully with no side effects. Then, about five years ago, I had prostate cancer and underwent a prostatectomy. Most recently, I was diagnosed with esophageal cancer, which required surgery, radiation, and immunotherapy.
Throughout the process, I approached it as both a patient and a physician-epidemiologist. I wanted to understand every step, every treatment. My wife, Yasmin, and I became experts in my care, which is crucial because cancer treatment involves so many choices.
Initially, I was told I wouldn’t be able to swim during chemotherapy. My doctors warned of infection risks. But I asked them epidemiologically what the actual evidence behind that was. Their answer was, “You could get infected.” So I proposed a deal: I’d monitor myself, take precautions, and if there was any sign of infection, I’d stop.
The result? I swam 300 kilometers while on chemotherapy. I even wrote about it afterward. The side effects were real, but they were manageable. More than anything, my swimming community kept me going. Some days, I was too weak to swim, tethered to my chemo pump. But on the days I could, seeing the sunrise over the water gave me a sense of awe and purpose. It also deepened my faith. I found great comfort in Jewish wisdom during that time.
After surgery, they removed my entire esophagus. Again, I was told swimming wouldn’t be possible due to reflux issues. But I started back slowly with my water aerobics group. I realized I wasn’t swallowing water, so there was no real risk. With adjustments, I returned to full swimming.
This experience has reshaped my perspective. Going forward, I want to help others understand the non-medical aspects of cancer recovery. Physical activity not only helps but actively reduces treatment side effects. There’s strong evidence for this in breast cancer patients, and I believe it applies broadly. Staying active is key, even when facing illness.
Yet we don’t talk about it enough. Normally, when you're diagnosed, you’re told to take it easy and listen to your body. But what does that even mean? If you feel slightly tired, do you just collapse and rest for a week? No. I think you should be under a little bit of stress, but not to an extreme. Don’t succumb to the first wave of exhaustion because the evidence shows that moderate activity reduces severe side effects of chemotherapy. I never even had to touch my anti-nausea medication. That’s rare.
Another major issue is diet and nutrition. We still don’t get high-quality advice in this area. Protein deficiency, for example, is a real risk. Medical nutrition products are available on the shelves, but many don’t have the taste, flavor, or creatine content that truly supports long-term health.
Beyond the Physical
Derek: Then, there’s the spiritual side. People need to engage in whatever they feel is most appropriate for their well-being. Some cancer institutions are beginning to integrate spiritual support early on, but I think this should be expanded to all chronic diseases. The biggest challenge of living with cancer (or any chronic illness!) is the uncertainty. You don’t know what the next month, year, or five years will bring. The key is staying positive and focusing on the next set of tests.
Rachael: That’s inspiring. The concept of awe is so interesting, it’s about recognizing that we’re part of something greater.
Derek: Absolutely. Interestingly, there’s a major review from the University of Zurich on spirituality and health. The WHO originally debated including “spiritual” in the definition of health back in its early days. The Swiss delegation proposed that health should encompass complete social and spiritual well-being. It didn’t make it into the final definition, but for decades, efforts have resurfaced to integrate it.
When I was at WHO in the 90s, I revisited this idea. There was significant support globally, but it ultimately didn’t pass. Now, with rising levels of anxiety, depression, and what we call “deaths of despair,” there’s renewed interest. Surveys show that in many low- and middle-income countries, 70-80% of people believe spiritual health is essential to physical and mental well-being. In wealthier nations, that number is lower, around 50%.
We can’t ignore this. As populations age and mental health crises rise, spirituality becomes a crucial complement to conventional healthcare.
Rachael: That’s a conversation worth continuing.
Thank you so much, Derek, for sharing your story with us!
If you would like to be featured or know someone who would be great to feature, please don’t hesitate to email rachael@jenerise.com 😊
We all rise together,
Rachael Jennings | Co-Founder + CBO, Jenerise
