Colonies foraging heavily on Camellia oleifera are reported to suffer digestive disturbance, brood loss and adult mortality.
Chinese research attributes the effect to α-galactoside oligosaccharides in the nectar and pollen that honey bees cannot digest well, causing larval rot and bloated workers. Feeding larvae the digestive enzyme α-galactosidase improved their survival, and colonies kept in the forests for years carry more gut bacteria able to break the sugars down. Yet the bees remain useful pollinators of the crop.
What this does not claim: This is not a claim that the honey is harmful to people. The problem described is one for the colony, not the consumer, and the sources read report no harm to people.
- Honey bee pollination of Camellia oleifera and mitigation of toxic crop nectar — Insects (2025) · Peer-reviewed article Link