Bee decline could increase malnutrition and disease risk

More than half of people living in four of the world’s poorest countries could be newly at risk for malnutrition if bees and other pollinating animals continue to decline, according to a new study by researchers from Harvard T.H. Chan School of Public Health and the University of Vermont. Pollinators help improve crop yields, and their loss could lead to a decline in the availability of foods that provide key nutrients to vulnerable populations.

The study was published online January 9, 2015 in PLOS One.

The researchers compared diets in Zambia, Mozambique, Uganda, and Bangladesh, focusing on the importance of pollination to the production of staple foods. They found that foods providing vitamin A were most dependent on pollinators for successful yields. For example, mangoes are a regular source of vitamin A in some regions. The loss of pollinators could reduce mango yield by 65 percent and result in vitamin A deficiencies — which can lead to blindness and increase death rates for some diseases, including malaria.

“This is the first study that quantifies the potential human health impacts of animal pollinator declines,” author Samuel Myers, senior research scientist in the Department of Environmental Health at Harvard Chan School, said in a statement. Other studies have shown links between pollinators and crop yields — and between crop yields and the availability of food and nutrients. “But to evaluate whether pollinator declines will really affect human nutrition, you need to know what people are eating.”