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At Helderberg Family Practice, we’re always excited to share the latest health research that can help you live a longer, healthier life. A recent study from Switzerland, called the DO-HEALTH trial, has caught our attention—and it might catch yours too. Published in the journal Nature Aging in 2025, this study suggests that taking omega-3 and vitamin D supplements, along with regular exercise, could slow down biological aging in older adults. It’s an exciting finding, but before you rush to stock up on supplements, let’s take a closer look at what the study found, what it means for your health, and why you should always talk to your doctor before making changes to your routine.
The DO-HEALTH Study: A Closer Look
The DO-HEALTH study, conducted by researchers in Switzerland, involved 777 participants aged 70 to 85 years old. This group was part of a larger randomized clinical trial that ran for three years, from 2012 to 2014, across five European countries. The participants were generally healthy, active older adults, which makes the findings particularly relevant for those of us who are aging but still feeling good. The study tested three interventions: a daily omega-3 supplement (1 gram, algae-based), a daily vitamin D supplement (2,000 IU), and a simple at-home exercise program (30 minutes of strength training three times a week). Participants were assigned to different groups, with some receiving just one intervention, others a combination, and some a placebo.
The researchers measured biological aging using tools called epigenetic clocks, which look at changes in DNA methylation—a process that reflects how our cells age. Biological age is different from your chronological age (the number of candles on your birthday cake). It’s a measure of how old your body seems at a cellular level, influenced by factors like genetics, lifestyle, and environment. At the end of the three-year trial, the results were promising: participants who took omega-3 supplements alone saw their biological aging slow by about three to four months. That means their cells appeared younger than expected for their age—a small but meaningful difference.
Even more exciting, the effect was stronger when omega-3 was combined with vitamin D and exercise. The combination group saw additional benefits, including a 61% reduction in cancer risk and a 39% reduction in pre-frailty (a state that often precedes frailty or weakness in older age). The study also found that omega-3 alone reduced the risk of falls by 10% and infections by 13%. These findings, led by Professor Heike Bischoff-Ferrari of the University of Basel, suggest that simple, accessible strategies like taking omega-3 and vitamin D, along with staying active, could have a real impact on healthy aging.
Why Omega-3 and Vitamin D Might Help
So, why might omega-3 and vitamin D have these effects? Omega-3 fatty acids, found in fatty fish like salmon, tuna, and mackerel, as well as in algae-based supplements, are known for their anti-inflammatory and antioxidant properties. Inflammation and oxidative stress are major drivers of aging and age-related diseases, so reducing them can help keep your cells healthier for longer. In the DO-HEALTH study, omega-3 seemed to slow down the biological aging process by protecting DNA from damage, which is a key factor in how our bodies age.
Vitamin D, often called the “sunshine vitamin,” plays a crucial role in bone health, immune function, and even mood. Many people, especially older adults, don’t get enough vitamin D from sunlight or diet alone, which is why supplements can be helpful. In the study, vitamin D appeared to work alongside omega-3 to enhance the anti-aging effects, possibly by supporting overall cellular health and reducing inflammation. The exercise component—30 minutes of strength training three times a week—added another layer of benefit by improving muscle mass, bone density, and overall physical function, all of which contribute to a longer, healthier life.
The Bigger Picture: What This Means for You
The DO-HEALTH study is exciting because it shows that small, manageable changes—like taking a daily omega-3 supplement, getting enough vitamin D, and staying active—might help you age more gracefully. A three- to four-month slowdown in biological aging might not sound like much, but over time, these small effects can add up. The study’s authors noted that if these benefits are sustained, they could lead to a lower risk of age-related conditions like cancer, frailty, and infections, which is a big deal for public health.
Here in the Helderberg area, where we’re surrounded by natural beauty and opportunities to stay active, these findings feel especially relevant. Whether you’re walking the trails of the Helderberg Nature Reserve or enjoying a stroll along the beach in Somerset West, adding a bit of strength training to your routine could amplify the benefits of omega-3 and vitamin D. And if you’re already a fan of fish or take a daily vitamin, you might be on the right track—but there’s a catch, and it’s an important one.
A Word of Caution: Don’t Overdo It
While the DO-HEALTH study is promising, it’s not a green light to start taking handfuls of supplements without guidance. At Helderberg Family Practice, we’ve seen firsthand how well-meaning health choices can sometimes lead to unexpected problems. Supplements like omega-3 and vitamin D are generally safe when taken in the right amounts, but more isn’t always better—and taking too much can be harmful.
For example, taking high doses of vitamin D (well above the 2,000 IU used in the study) can lead to a condition called hypercalcemia, where there’s too much calcium in your blood. This can cause symptoms like nausea, weakness, and even kidney problems. Similarly, while omega-3 supplements are often well-tolerated, taking too much can increase the risk of bleeding, especially if you’re on blood-thinning medications like aspirin or warfarin. Some studies have also raised concerns about omega-3 supplements potentially increasing the risk of heart issues in people who are already healthy, though the evidence is mixed and more research is needed.
Another thing to consider is that supplements can interact with medications or other health conditions. For instance, if you have a history of kidney stones or thyroid issues, high doses of vitamin D might not be safe for you. And if you’re already getting plenty of omega-3 from your diet—say, by eating fatty fish twice a week—you might not need a supplement at all. The DO-HEALTH study used 1 gram of omega-3 and 2,000 IU of vitamin D daily, which are considered safe doses for most people, but everyone’s needs are different.
Why You Should Talk to Your Doctor First
This is where your doctor comes in. Before you start any new supplement, it’s crucial to have a conversation with your healthcare provider. At Helderberg Family Practice, we take a personalized approach to your health. We’ll look at your diet, lifestyle, medical history, and even your blood levels of nutrients like vitamin D to determine what’s right for you. For example, if you’re already low in vitamin D (common in older adults, especially in winter), a supplement might be a great idea. But if your levels are already optimal, adding more could do more harm than good.
Your doctor can also help you avoid potential interactions. If you’re taking medications for high cholesterol, blood pressure, or other conditions, omega-3 and vitamin D might affect how those drugs work. A quick chat with your doctor can help you find the right balance, ensuring you get the benefits of these nutrients without the risks. Plus, we can recommend high-quality supplements—because not all products on the shelf are created equal. Some may contain less of the active ingredient than they claim, or even unwanted additives.
A Balanced Approach to Healthy Aging
The DO-HEALTH study reminds us that healthy aging isn’t about a single magic pill—it’s about a combination of smart choices. Omega-3 and vitamin D supplements can play a role, but they work best when paired with other habits, like regular exercise and a balanced diet. In the Helderberg area, we’re lucky to have access to fresh, local seafood like snoek and sardines, which are rich in omega-3s. Adding a serving of fatty fish to your weekly meals can be a delicious way to get these nutrients naturally. And don’t forget about sunlight for vitamin D—just 10 to 15 minutes of sun exposure a few times a week can make a difference, though you’ll want to balance that with sun safety to protect your skin.
Exercise is another key piece of the puzzle. The DO-HEALTH study used a simple strength-training program, but even a daily walk can help. Staying active keeps your muscles strong, your bones healthy, and your heart in good shape—all of which contribute to a longer, more vibrant life. If you’re not sure where to start, we can help you find an exercise routine that fits your needs and abilities.
Let’s Work Together for Your Health
The DO-HEALTH study offers a hopeful message: small changes, like taking omega-3 and vitamin D supplements and staying active, might help you age more gracefully. But the key is to approach these changes thoughtfully, with guidance from your doctor. At Helderberg Family Practice, we’re here to help you navigate the latest research and make choices that are right for you. Whether you’re curious about supplements, want to start an exercise program, or just need a check-up, we’d love to support you on your journey to healthy aging.
Ready to take the next step? with us today, and let’s talk about how we can help you live your healthiest, longest life—safely and sustainably.
