Fewer insects, fewer nutritious crops: pollinator decline imperils human health

Biodiversity loss is directly threatening human health and welfare, according to new research led by the University of Bristol. The study, published in Nature today reveals, for the first time, how the decline of insect pollinators undermines essential ecosystem services that support human nutrition and livelihoods. Biodiversity also plays a vital role in supporting people’s everyday health and resilience.

It’s been long known that insect pollinators are vital for producing many of the fruits, vegetables and pulses that supply essential vitamins and minerals in human diets. Yet clear evidence has been limited as to how the decline of pollinators affects people — until now.

Working in 10 smallholder farming villages and their surrounding landscapes in Nepal, the study traced the full chain of connections between wild pollinators, crop yields and the nutrients families rely on. By tracking diets, crop nutrients and the insects visiting those crops over a year, the research team showed how pollinators directly support both nutrition and livelihoods.

The study found insect pollinators are crucial for both the nutrition and income of farming families, and pollinators were responsible for 44% of people’s farming income and contributed more than 20% of their intake of vitamin A, folate and vitamin E.  When pollinators decline, families risk poorer nutrition leading to higher vulnerability to illness and infections, and deeper cycles of poverty and poor health. One quarter of the global population currently suffer from this ‘hidden hunger.’

The research showed there is real potential for positive change — when communities support pollinators, their nutrition and income can improve. Simple steps like planting wildflowers, using fewer pesticides or keeping native bees can help boost pollinator numbers, strengthening both nature and people’s wellbeing.

Even though smallholder farmers are highly vulnerable to biodiversity loss, by applying this approach these practical local actions could enhance their food security and economic resilience.  The findings could also help improve the health and livelihoods of millions of smallholder farmers around the world.

Said Dr. Samuel Myers, faculty director of the Johns Hopkins Institute for Planetary Health and a co-author of the report: “This study reveals in detail what the field of Planetary Health asserts: that human wellbeing and the state of our planet’s natural systems are intimately connected. As we tear larger and larger rents in the fabric of life we degrade the future of vulnerable populations across the globe. Protecting natural systems is foundational to securing a livable future for humanity and the rest of life on Earth.”

Dr Thomas Timberlake, post-doctoral research associate and lead author, who carried out the study while at the University of Bristol and is now at the University of York, said: “Our study shows that biodiversity is not a luxury – it is fundamental to our health, nutrition and livelihoods. By revealing how species like pollinators support the food we eat, we highlight both the risks of biodiversity loss for human health, but also the powerful opportunities to improve human lives by working with nature.”

Dr Naomi Saville from the University College London Institute for Global Health, who coordinated the nutrition work in Nepal, said: “Over half of the children in our study were too short for their age, which is largely driven by poor diets that depend upon insect pollinated vegetables, legumes and fruits. As pollinator biodiversity declines, loss of vitamin A, folate and protein from the diet can further damage these children’s health and development, so efforts to restore pollinators are crucial.”

The research has shown that human health is deeply tied to the health of nature. By tracking how pollinators support food production and diets, the study has revealed that biodiversity loss isn’t just an environmental problem, it threatens public health and economic stability — as highlighted in the recent UK government national security assessment on global biodiversity loss.

With around two billion people relying on smallholder farming and with many facing vitamin deficiencies, protecting the ecosystems that support nutritious food is essential and crucial for sustainable development.

The study’s findings offer a practical framework to help policymakers and farmers design more nature‑positive farming systems. Although the research is focused on Nepal, the same connections shape food systems everywhere. Diets, even in industrialized countries, still depend on the pollinators and ecosystems that sustain global agriculture.

The research team — spanning universities and non-governmental organizations (NGOs) across Nepal, UK, US and Finland — is now putting their findings into action across Nepal to tackle pollinator declines and repair the pollination systems that support food production.  Working with farmers, local organizations, researchers and government partners, they are helping people understand the value of pollinators and how to support them in everyday farming.

By demonstrating why pollinators matter, and sharing simple, practical techniques to support them, the researchers are already seeing farmers adopt changes that boost crop yields, nutrition and income.

The study is also informing a new National Pollinator Strategy for Nepal, helping make pollinator‑friendly farming part of everyday agriculture. Together, these efforts show how scientific evidence can drive real-world change, improving people’s health, livelihoods and resilience by restoring biodiversity.

Paper

‘Pollinators support the nutrition and income of vulnerable communities’ by T. P. Timberlake, J. Memmott et al. in Nature

Notes to editors:

DOI: 10.1038/s41586-026-10421-x

Images from the study are available to download from the following URL:

https://fluff.bris.ac.uk/fluff/u1/ficmc/Zwx39p2gBCxVgo4Wt0GI6QT3O/

The images are for single use only to be used to illustrate findings from this study, they should be credited and should not be archived.

For further information or to arrange an interview with Dr Thomas Timberlake and Professor Jane Memmott please contact Joanne Fryer [Mon to Weds], email joanne.fryer@bristol.ac.uk, mobile: +44 (0)7747 768805 or Caroline Clancy-Cottle [Weds to Fri], email caroline.clancy@bristol.ac.uk, mobile: +44 (0)7776 170238 in the University of Bristol News and Content Team.

Issued by the Research News and Content team at the University of Bristol