The nature cure
Protecting biodiversity and natural ecosystems is vital for human health, medicine discovery, and sustainable wellbeing.
In the tropical highlands of Madagascar, a flower was overlooked. Five soft petals, pale pink or white, arranged in a star-shaped pattern. These flowers sprout from low bushes nestled among red soils and rustling grasses. It is called tsimanila in Malagasy: “that which does not die”. Western medicine calls it Catharanthus roseus, or Madagascar periwinkle. But today, the world knows it as something more: vinblastine and vincristine, the cornerstone treatments for childhood cancers, including leukaemia and Hodgkin’s lymphoma. This single flower has saved countless lives.
Prior to 1960, acute lymphoblastic leukemia, the most common childhood cancer, was considered universally fatal. Less than 10 per cent of children survived this deadly disease, with most living only weeks to months after diagnosis. Chemotherapy was in its infancy, and doctors had few tools at their disposal.
That began to change in the late 1950s and early 1960s, when researchers began investigating the Madagascar periwinkle as a possible treatment for diabetes. In early tests, the plant didn’t lower blood sugar as hoped. But what they found instead was far more extraordinary: the plant extracts suppressed white blood cell proliferation.
This unexpected finding led to the isolation of two powerful alkaloids: vinblastine and vincristine. The first became the frontline treatment for Hodgkin’s lymphoma; the latter emerged as one of the most effective weapons against childhood leukaemia, especially acute lymphoblastic leukaemia.
These plant-derived compounds became the backbone of modern chemotherapy, and survival rates soared. Today, the cure rate for Hodgkin’s lymphoma and acute lymphoblastic leukaemia sits at over 90 per cent in most developed countries. And behind both? A pink flower from the red soils of Madagascar that has saved the lives of hundreds of thousands of children.
A natural pharmacopoeia
More than 80 per cent of registered medicines today are derived from, or modelled on, compounds found in nature. Aspirin traces its lineage to the willow tree, whose bark has soothed pain and fever from ancient times to the present day. Morphine was born from the opium poppy, its milky latex harvested to ease suffering and pain. Quinine, the first effective treatment for malaria, was found in the bitter bark of the South American cinchona tree, a remedy passed down through Indigenous peoples long before it was bottled in glass. The Pacific yew tree gave us paclitaxel, a chemotherapy agent so potent it changed the odds for countless cancer patients.
Even today, medicines used to treat conditions such as Parkinson’s disease, Alzheimer’s and parasitic infections often contain molecules first discovered in plants. In oncology alone, nearly 70 per cent of drugs used for cancer are found in or inspired by nature.
Nature is not only the world’s most powerful pharmacy. It is humanity’s most vitally important healthcare system. In fact, the very functioning and survival of humanity is inextricably and directly tied to the plants, animals and ecosystems that make up the natural world. From tiny insects to vast forests, nature carries out life-sustaining processes so seamlessly, we often forget they’re happening at all.
Nature in action
Trees act as the earth’s lungs, filtering pollutants and producing the oxygen we breathe. Pollinators like birds, bees and bats fuel our global food system by spreading pollen across plants and allowing crops to reproduce. Healthy soil puts food on our plates, purifies our water, protects us against flooding and combats drought. Coral reefs protect coastlines from erosion while supporting fisheries and tourism. Nature provides the raw materials for our homes, the energy we use and the clothes we wear.
Every second, nature performs miracles we barely notice. It filters our water, purifies the air, protects us from infectious disease and gives us medicines that ease pain and fight illness. It holds the molecular blueprints for drugs we already rely on, and for thousands more yet to be discovered.
Nature also heals us in other ways. The feel of a forest. The sound of the ocean. The scent of flowers. The presence of birdsong. Time spent in nature delivers measurable (and immeasurable) improvements in mental and physical health: exposure to nature lowers cortisol levels, reduces inflammation, enhances immune function, improves sleep quality and even boosts cognitive performance.
Green prescriptions
So profound are these benefits that some countries have formally integrated nature into public health policy. In Japan, forest bathing (shinrin-yoku) is a recognised form of preventative medicine, prescribed to alleviate anxiety and restore balance in an overstimulated world. South Korea has taken it a step further, establishing state-funded forest healing centres that provide guided therapy in nature for people living with PTSD, depression, chronic stress and lifestyle-related diseases.
In Scotland, general practitioners can issue “green prescriptions”, directing patients to engage in nature-based activities such as birdwatching, beach walks or time in healing forests, as a way to improve mental health and cardiovascular fitness. While in Canada, doctors can formally prescribe time in nature, up to two hours per week, to improve wellbeing and reduce anxiety.
Even government planners are beginning to formally recognise the role of nature in protecting and defending our homes, economies and future safety and wellbeing.
Life support
Mangrove forests, for instance, are the most stalwart defenders of communities. Their intricate root systems calm waves, absorb storm surges and hold soil in place, offering powerful natural protection against cyclones, erosion and flooding. A global study found that mangroves save more than 15 million people from flooding each year and reduce storm damage costs by over US$65 billion. Recognising this, urban and environmental planners are integrating mangrove conservation and restoration into climate-resilience strategies and community planning.
Even wild species offer protection and cost savings to communities. Beavers create wetlands that enhance biodiversity, improve water quality, mitigate flooding and provide natural services worth millions. In fact, a long-delayed government project to build a dam and restore wetlands in Czechia was quietly overtaken by beavers, who did the job themselves — saving taxpayers US$1.2 million in the process.
Without waiting for permits or paperwork, the beavers built their own structure and restored the wetland that had been earmarked for development.
Every thread of civilisation, every medical innovation, every breath we take owes its roots to the natural world. Nature isn’t just our landscape — it is our life-support system. And when that life support system suffers, so too does our health, humanity and livelihood.
This became tragically clear in the 1990s, when something strange began to unfold across India.
Vulture vulnerability
Vultures, once a common presence in both rural and urban Indian landscapes, began to vanish, baffling conservationists and government officials alike. Vultures perform one of the most crucial public health services in the environment: by consuming rotting carcasses, they prevent the spread of deadly disease, reduce greenhouse gas emissions and other pollutants and ensure ecological balance. They are, in essence, nature’s cleanup crew — underappreciated and utterly indispensable.
In less than a decade, Indian vulture populations fell from 50 million to just a few thousand. Without vultures, carcasses remained in the open for longer, attracting rats and feral dogs. Rabies cases soared. Bacterial contamination of water sources increased and a sudden spike in the dumping of livestock remains led to broader environmental degradation.
The consequences of their disappearance were staggering. Half a million people died, ecosystems were degraded and the cost to India’s economy reached US$350 billion.
In 2004, scientists discovered the cause of the vulture’s decline. A veterinary drug called diclofenac (used widely to treat livestock) proved fatally toxic to vultures. When the birds fed on animals recently treated with the drug, it caused kidney failure, killing them in vast numbers.
In 2006, India, along with Pakistan and Nepal, banned the veterinary use of diclofenac, a crucial step in what has become a slow, determined effort to restore vulture numbers. Recovery is underway, but it is cautious and hard-won.
A vanishing resource
Worldwide, the decline of nature is setting off a cascade of consequences that are felt across human healthcare systems, economic systems and social systems. This extraordinary system, the world’s original pharmacy, is vanishing.
Every year, humanity clears 10 million hectares of forests, an area the size of Portugal. More than 75 per cent of Earth’s land areas have been substantially degraded and destroyed, threatening the wellbeing of billions of people. Conservative estimates suggest we lose one potential life-saving drug every two years due to deforestation, pollution and biodiversity collapse.
As science communicator Peter Bickerton writes: “Right now, the cure for cancer, or COVID, could be going extinct.”
With every tree felled, with every ecosystem cleared, we are not just losing vital medicine, but the very thing that keeps us alive: nature.
The World Health Organisation now calls climate change (and related biodiversity loss) the greatest health threat of the 21st century. Yet, we have become so profoundly disconnected from the natural world that we often fail to recognise that everything we depend on — our air, food, water, shelter and even our wellbeing — comes from nature.
It’s time to rethink the very foundations of healthcare, not just as hospitals and treatments, but as the living systems that keep us well. The air we breathe. The soils that grow our food. The microbes that share our bodies. The forests that produce our medicines. The natural world deserves to thrive, not just for what it gives us, but for its own intrinsic right to exist.
This calls for more than minor adjustments. It requires a concerted effort to restore ecosystems, reimagine economies and recognise a truth we can no longer ignore: human health is inseparable from the health of the planet.
We stand at a crossroads. The same natural systems that gave us antibiotics, chemotherapy and antimalarials are vanishing before our eyes. Deforestation, climate change, pollution and habitat loss are not just environmental issues; they are medical emergencies. They erode our natural pharmacies, weaken ecosystem resilience and exacerbate the spread of zoonotic diseases such as Ebola, COVID-19 and others.
But solutions exist, and they are within reach.
A new understanding
We’re beginning to rediscover what many Indigenous and ancient cultures have always known: we are not separate from nature. We are part of it. This isn’t philosophy, it’s biology: when ecosystems are protected, people thrive.
Global health leaders are beginning to catch up. The World Health Organisation now advocates for what’s known as the One Health approach, a growing movement that recognises the deep interconnection between human, animal and environmental health.
Nature, after all, is the world’s original pharmacy, an intricate, living network that has quietly underpinned human health and wellbeing for millennia. As climate pressures mount and biodiversity declines, we must treat ecosystems not as optional scenery, but integral components of human health infrastructure.
This means widening our understanding of healthcare. Not just as hospitals and treatments, but as the living systems that sustain life and keep us well: the forests that filter our air, the soils that grow our food, the species that heal us.
We are not separate from nature. We are nature, healing itself or harming itself.
The cure for the next great illness might be blooming right now in a forest earmarked for clearing. The question is: will we protect it in time?
