Pollinators in Peril: Scientists Reveal Hidden Human Health Costs of Disappearing Bees

The Hidden Connection Between Bees and Human Health

There are few ways in and out of Nepal's Jumla district. The Karnali highway, considered one of the world's most dangerous roads, provides the only land link, splicing through the Himalayas to connect Jumla's terraced valleys to the rest of the country. As such, the 120,000 people that live there are almost entirely self-sufficient, with most of them eating and selling what they grow.

It's a tenuous existence, plagued by food insecurity and malnutrition. In recent years, local beekeepers have bemoaned languishing hives and dwindling honey production, observing that roughly half of their bees seem to have vanished over the past decade. These concerns, however, ignore an even more insidious impact.

Groundbreaking Research in Nepal's Remote Jumla District

"They saw these bees as valuable for honey, but they didn't really realise that they were also essential for supporting the production of their crops," says Thomas Timberlake, an ecologist at the University of York.

In a study published last month in the journal Nature, Timberlake and his colleagues set out to quantify just how important the area's pollinators were to the health of those living in 10 remote Jumla villages. To do so, they tracked people's diets, crop yields, and farming income over a one-year period, alongside pollinator interactions with their crops – including the painstaking process of counting pollen granules on fuzzy bee bodies.

Quantifying the Impact: Pollinators' Role in Nutrition and Income

It turned out that pollinators were directly responsible for more than 20% of inhabitants' vitamin A, vitamin E and folate intake, and 44% of their farming income. It is the first study of its kind to provide direct evidence of the bond between pollinators and human health.

"These types of communities are so vulnerable because they are very isolated geographically. There are not good trade links into there, and they're very poor," says Timberlake. "If the yields of local fruits and vegetables decline, they are not going to be able to supplement that by buying imported foods. They just are not going to eat those fruits and vegetables."

Global Decline of Pollinators and Its Consequences

Ecologists have long stressed the importance of pollinators for human health, yet measuring the direct benefits to our wellbeing is still an evolving field of study. It is also one that has become all the more urgent as meadows fall silent and the droning hum of bees fades to a whisper. Over the past decade, scientists have sought to uncover precisely how pollinators help to boost nutrition, revealing the hidden health costs of pollinator declines.

In 2015, a modelling study in the Lancet found that if all of the world's pollinators were to collapse, an additional 1.4 million people would die every year from malnutrition-related diseases. But Sam Myers, the director of the Johns Hopkins Institute for Planetary Health and co-author of the research, says that he desired to move beyond the hypothetical and assess real-world impacts. "We hope that pollinators are not going to collapse completely. So … what can we say about the penalty we're paying today from insufficient pollinators?"

Future Outlook for Pollinators and Human Well-being

While birds, bats and butterflies are all considered pollinators, few species do as much for the world's flowers and crops as bees. Honeybees and wild bees are the most prolific pollinators, effortlessly moving pollen from the male anther of a flowering plant to the female stigma. This process fertilises the plant so it can reproduce, generating seeds and fruits. About three-quarters of all agricultural crops rely on pollinator services.

That should be cause for concern, experts say, as pollinators across the world are in peril. As forests, grasslands and wildflower meadows have been converted to industrial-scale agriculture and development, bees and butterflies have been left without food or nesting sites. Pesticides – especially neonicotinoids, which interfere with the bees' nervous system – are also taking a toll, alongside the climate crisis and the spread of invasive species.

When IPBES, the intergovernmental platform for biodiversity science, last took stock of pollinator populations in 2016, it estimated that more than 40% of bee species may be threatened globally, though many lacked sufficient population data.