The Ocean Behind Human Health: Why a healthy ocean = a healthy human

Modern conversations around health are increasingly focused on optimisation. Diets, training plans, wearables, longevity science, metabolic health – the list goes on. There is a strong cultural emphasis on improving the individual through constant refinement.

But this framing that’s taking over the world often ignores something more fundamental: what enables human health in the first place.

Like in some of our other articles in this instance the ocean is once again treated as something separate from everyday life despite being deeply embedded in it – supporting medicine development, nutrition security, environmental stability, and mental wellbeing.

A healthy ocean supports healthy people. Therefore, a degraded ocean creates serious health risks that eventually lead back into human systems.

The ocean in modern medicine

Perhaps unsurprisingly some of the most widely used and important medical advances right now are linked, either directly or indirectly, to biological processes in nature including marine ecosystems.

GLP-1 medications like Ozempic and Wegovy have taken the world by storm in the last few years and become central to global discussions around obesity, diabetes, and general metabolic health.

And yes, these drugs wouldn’t be here and readily available without advanced pharmaceutical research and development, but they also sit in this unique wide pattern of medical science where a reliance on understanding biological systems across species is needed to identify useful physiological mechanisms that can crossover to human medications.

Aquatic organisms have played a long-standing role in this broad scientific foundation. Many marine organisms have been studied for decades to better understand their metabolism, hormone signalling, and adaptation to environmental stressors all in the assumption that understanding these organisms better would feed into human medicine.

One of the most direct and maybe striking examples of ocean-linked healthcare is the horseshoe crab. Despite the name it is not a real crab, but more closely related to spiders & scorpions. If you’ve ever seen those photos online of beaches covered in strange-looking armoured shells you’ve probably seen a horseshoe crab. But what most people don’t realise is the important role this amazing species plays in all our lives. They have actual blue blood that contains a substance called Limulus Amebocyte Lysate (LAL), which reacts to bacterial toxins. For decades, pharmaceutical companies have relied on LAL testing to ensure vaccines, injectable medicines, intravenous drugs, and medical devices are free from potentially dangerous contamination before a patient uses them. In the manufacturing of medical products including the COVID-19 vaccines this testing has played a critical hidden role in safeguarding public health.

The ocean’s influence on health is not limited to hospitals and pharmaceuticals. Marine derived compounds are also finding their way into wellness and aesthetics culture too. Seaweed extracts, marine collagen, and algae-derived ingredients are now common features in skincare, products and supplements, while salmon-sperm facials and injectable treatments have attracted a lot of attention on social media in recent years. It’s almost irrelevant as to whether these treatments ultimately prove to be revolutionary or just stay as another wellness trend, because they highlight a broader shift in how we view the ocean - as a source of products linked to health, ageing, and appearance. In a culture increasingly focused on personal optimisation, longevity and aesthetics, the ocean is a key player.

The ocean represents a major frontier for future medical breakthroughs. Marine organisms like sponges, corals, algae and potentially undiscovered deep-sea species produce a huge range of bioactive compounds. Right now, some of these are being investigated for potential uses in cancer treatment, antimicrobial resistance, and inflammatory disease.

At this point it is really important to remember we’ve only explored a fraction of the ocean and much of marine biodiversity remains undiscovered, particularly in the deep ocean. In practical terms this means the ocean is one of the most underutilised sources of biomedical innovation left on the planet.

Nutrition: the ocean on our plate

Seafood is a globally significant source of high-quality protein, omega-3 fatty acids, and essential micronutrients all playing a role in supporting cardiovascular, neurological, and developmental health. For many populations it is an essential part of everyday nutrition. According to the FAO, aquatic animal foods provide at least 20% of animal protein intake for around 3.2 billion people.

The global demand for food is increasing which obviously puts extra pressure on food systems. For the ocean that is where sustainable aquaculture becomes a key player. When it is managed responsibly it can provide nutrient-dense food while importantly reducing pressure on wild fish stocks. However, this is not automatic. Some forms of aquaculture still rely on wild-caught fish for feed, which can create an energy and nutrition loss if small fish that could feed people directly are instead used to grow higher-value farmed species.

At the same time ocean-based innovation is beginning to challenge what we even consider ‘food production’.

One really exciting, innovative example is Nemo’s Garden off the coast of Noli in Liguria, Italy. They have created an experimental system that grows terrestrial crops underwater inside biospheres anchored to the seabed. The aim of the project is to explore whether stable marine conditions can support large scale agriculture in the face of growing land scarcity, water stress and climate uncertainty. It is obviously still experimental but points to a wider shift in thinking – that the ocean plays a role in the future of food systems beyond fisheries and aquaculture.

But all of this is dependent on healthy marine ecosystems. Pollution, overfishing and environmental degradation are influencing biodiversity, yes, but also safety, availability, and quality of food from the ocean.

So, in that sense; ocean health is inseparable from food and nutrition security.

There is also an equity issue here. In many coastal communities, especially in parts of the Global South, fish and shellfish are not a luxury food but a key source of protein and micronutrients. In our global seafood market, highly nutritious marine foods can be exported away from the communities that depend on them most, while those same communities may be more exposed to the impacts of ocean warming, acidification and overfishing.

When ocean health becomes human health

Like many things this connection becomes most visible when it breaks down -let’s think about ocean acidification and nutrition security.

Ocean acidification is one of the less visible ways ocean change can become a human health issue. As the ocean absorbs more carbon dioxide, seawater chemistry changes and it can become harder for shell-forming organisms such as oysters, mussels, clams and scallops, along with some crustaceans during vulnerable life stages.

This matters because shellfish are part of both food systems and livelihoods. If oysters, mussels and other bivalves become harder to grow, that affects aquaculture, coastal economies and access to nutrient-rich food. The issue is not only whether people have enough calories, but whether they have access to foods that support healthy development, immunity and long-term wellbeing.

Some of the smallest shell-forming organisms, including plankton, are also vulnerable to changes in ocean chemistry. Because these species sit at the base of marine food webs, impacts can ripple through ecosystems and eventually affect the seafood people rely on.

Another example is sewage discharge into coastal waters. Contaminated bathing waters can expose swimmers, surfers, and coastal communities to harmful pathogens, while also reducing access to spaces that support recreation and wellbeing. Most open water swimmers now know not to swim after rainfall.

This connection was brought into the public spotlight recently through the Channel 4 drama ‘Dirty Business’, which explored the UK’s sewage pollution crisis and the real human stories behind it. Among them was the poignant case of 8yr old Heather Preen who died after contracting E. coli after being exposed to contaminated water during a family holiday in Devon. The series highlighted the human cost of a failing water quality system.

Even if cases like Heather’s are extremely rare, they serve as a stark reminder that sewage pollution isn’t just about unpleasant beaches or poor environmental stewardship. At its core it’s about protecting public health and ensuring people can safely enjoy and benefit from the ocean around them.

Warmer and more nutrient-rich waters can also increase the risk of harmful algal blooms in some places. These blooms can contaminate seafood, affect drinking and recreational water, and create health risks for people and animals. Again, this shows how changes in ocean and water quality can quickly become public health concerns.

Plastic pollution is another glaring global crisis. Microplastics are widespread across marine ecosystems and across global food webs. While the long-term health implications are still being researched, their presence alone highlights how closely humans and the ocean are now intertwined. Did you know we all have micro and nanoplastics in our bodies?

Blue spaces & mental wellbeing

Coastal environments, rivers, estuaries, and beaches – often referred to as ‘blue spaces’ are recognised for their positive effects on mental health and wellbeing. Some research suggests that having access to these environments can reduce stress, improve mood, and encourage physical activity.

While the exact mechanisms that cause this are still being studied the pattern is consistent; people tend to feel better when they’re near/in water.

Because of this, blue spaces are being considered alongside green spaces as vital public health assets. This shifts the way we view coastlines are more than just nature landscapes but also as a part of the infrastructure supporting mental and community wellbeing.

Therefore, access to clean, safe, and well-maintained coastal environments is not just a lifestyle benefit but a real health consideration.

What this means in practice

Being able to understand the ocean as a part of human health influences how we act at different levels.

For individuals, that means recognising that everyday choices are indirectly connected to ocean systems. So, choosing sustainably sourced seafood, reducing plastic use, and spending time in blue spaces are simple but meaningful ways to acknowledge this important link.

For healthcare organisations, it reinforces the importance of recognising the environmental determinants of human health. This is often described as planetary health: the understanding that human health depends on the health of the natural systems around us. So, supporting nature-based wellbeing approaches, reducing environmental impact and integrating planetary health perspectives into future healthcare planning are becoming increasingly relevant considerations.

For communities, it highlights the importance of protecting their marine environments as public health infrastructure. Clear bathing waters, restored coastlines, and accessible blue spaces are more than environmental goals – they’re key health assets.

The bottom line

The ocean is still being treated as something separate from human life, but it’s directly connected to our health.

It contributes to medical innovation, global nutrition, environmental resilience, influences environmental exposure risks, and supports mental wellbeing. These connections are practical and measurable.

A healthy ocean is therefore a fundamental condition for maintaining human health, and recognising this relationship is increasingly important in a world where both environmental and health challenges become more complex and interconnected.

 Written by Alana Wilson with editorial direction from Leanne Hepburn