Sanne Boesveldt awarded Vici grant to study how smell influences health and eating behaviour

Perhaps you are familiar with this: a whiff of simmering meat instantly takes you back to Christmas at your grandparents’ house. Or a sour, sweaty smell enters your nose and you find yourself back among the ropes, climbing frames and spotty teenagers in gym class. That is no coincidence, according to Sanne Boesveldt, Associate Professor of Human Nutrition and Health at Wageningen University & Research. “The bulbus olfactorius (the brain’s centre for smell) is located close to areas involved in memory and emotion. As a result, smell can have a direct influence on cognitive processes.”  

It is precisely this close link between smell and memory that Boesveldt aims to utilise to counteract memory loss. Previous studies have shown that so-called smell training to combat impaired olfaction, not only improves the sense of smell but may also have a positive effect on memory. Boesveldt now wants to investigate this systematically in a large group of people with mild memory problems. Participants will smell four different strong scents twice a day for several months. “Using specialised MRI scans, we will examine whether this leads to measurable changes in the brain,” Boesveldt explains.

In addition to this ‘standard’ scent therapy, Boesveldt plans to introduce a more advanced therapy in which participants not only smell an odour but also see its source through a virtual reality (VR) headset. “For example, the headset might show a rose garden while you smell a jar containing a rose scent,” she says. “The idea is that multisensory stimulation (engaging multiple senses at the same time) has a stronger effect.” 

The second part of the study focuses on the role that smell plays in food choices, particularly in people who lose weight using slimming medication such as GLP-1. Although this medication appears to be effective in treating obesity, researchers do not yet fully understand how GLP-1 alters eating behaviour or what happens in the brain. Boesveldt suspects that smell may also play a role here. “Smell and taste largely determine our food choices. From animal studies, we know that the olfactory bulb (the smell centre in the brain) contains receptors that GLP-1 can bind to.” This raises an intriguing question: does GLP-1 change the sense of smell, and does that in turn influence eating behaviour?

The study will follow participants who are starting GLP-1 medication. Researchers will measure their sense of smell, eating behaviour and brain activity before the first injection and at several points afterwards. Boesveldt and her colleagues will compare this group with people who lose weight through lifestyle and dietary changes without medication. “This way, we hope to distinguish between the effects of weight loss itself and effects that are specifically linked to GLP-1,” says Boesveldt. 

Although the research is fundamental in nature, Boesveldt sees clear societal relevance and future applications. “If we gain a better understanding of how smell contributes to changes in memory and eating behaviour, we may eventually be able to target these processes much more precisely.”

Receiving the Vici grant feels like special recognition to her. “It’s bizarre and surreal,” she says. “But above all, it feels like an enormous gift: I get to spend five years doing the research I want to do, based entirely on my own ideas.” 

In this funding round, NWO awarded a total of 39 Vici grants to researchers at Dutch knowledge institutions, including four to Wageningen-based researchers. The grant enables recipients to develop a research line and further build their research group over a five-year period. The Vici is one of the largest individual research grants in the Netherlands and is aimed at experienced researchers.

NWO also awards Veni and Vidi grants to earlier-career scientists, following Julius Caesar’s famous dictum: Veni, Vidi, Vici – I came, I saw, I conquered.

The other three Vici grants awarded in Wageningen went to:

• Eveline Verhulst, for research into the sexual development of male and female insects.
• Vera Ros, for research into hidden viruses in insects.
• David Ludwig, for research into the role of science in times of complex crises such as climate change.