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Cambridge Global Food Security

An Interdisciplinary Research Centre at the University of Cambridge

Tarra Penney is fascinated by human behaviour and why people do the things they do. She’s interested in supporting the prevention of chronic disease by understanding if, and how, changes in the food system influence population diet and health.

December 2017: Meet Dr Tarra Penney

Since moving to Cambridge from Canada in 2013, Tarra's research has gradually broadened in scope from the individual to the population-level, as she seeks to understand the multiple layers of influence on what people eat. Tarra is currently a Research Associate with the Food Systems and Public Health programme at Cambridge’s MRC Epidemiology Unit and Centre for Diet and Activity Research (CEDAR).


 Tarra Penney


Q: What’s the point of your research?

A: I’m interested in improving our understanding of how changes within the food system promote or undermine healthier diets at the population level. This includes identifying opportunities to evaluate changes that are occurring within the food system, which are often initiated outside of the domain of public health. So when, in 2016, the UK Government announced the Soft Drinks Industry Levy - a tax on importers and manufacturers of soft drinks with added sugar – our group, led by Professor Martin White, identified this as an important change in the food system to evaluate. 

Our study began this summer, with colleagues at CEDAR, the University of Oxford and London School of Hygiene and Tropical Medicine. It’s called the Soft Drinks Industry Levy Evaluation, and what’s quite novel and exciting is that the evaluation is grounded in a ‘systems approach’, to examine not only whether and for whom the levy has an effect on diet and health, but to understand the process by which the tax came about and any wider shifts in public, political, societal and industry attitudes toward sugar and the levy.

Q: How is this relevant to global food security?

A: It’s important to ensure that attempts to improve food security do not unintentionally undermine health. We’re not just interested in making sure people get enough calories in their diet; we want to make sure that what they’re eating is healthy too. Soft drinks are already consumed globally, and have been linked with overweight, obesity and diabetes worldwide – this includes both low- and middle-income countries. The World Health Organization has urged global action, including the use of fiscal policies to help reduce consumption. From this point of view, the results of the evaluation could be important for supporting this call to action and help to ensure that the right system-level incentives and disincentives exist to make sure healthy calories are used to address issues of global food security.  

Q: What do you enjoy most about your research?

A: I really enjoy taking what we’ve learned and sharing it with the public. This can be quite challenging, particularly in our field of dietary public health. Studying how environments and policy influence what we eat can seem far removed from the everyday experience of eating, and some of the messages are quite complex. For example if you ask people what influences their food choices, they’re far more likely to say their preferences are a major influence, rather than the use of shelf space in a supermarket or the availability of fast food on their commute to work.

I’ve been trying to come up with creative ways to share some of this research and worked with an artist, Aurora Cacciapuoti, to make a visual representation of the collection of environmental factors that influence what people eat. We developed an activity called Great Snackington that’s particularly popular with younger people. It’s a fun cartoon of a town that shows lots of places to get food like burgers, chips and ice-cream, and hidden within the scene is a salad that’s really difficult to find. It demonstrates, in an exaggerated way, our everyday struggle to choose healthy food in the face of food prices, promotions and advertising that can encourage us toward less healthy foods.

Q: What’s your favorite research tool?

A: I’d have to say the collective brain. This might sound a bit basic, but what I value most is a stack of sticky notes, a white board, and a discussion with colleagues. It never ceases to amaze me how quickly a problem can be solved, or a path through confusion can be clarified, using insights and support from others.

Q: What might other people be surprised to learn about you?

A: I have a reputation for being pretty organised – I’m a fan of things like using meeting agendas, working with timelines, developing structured plans, and thinking through risks in advance. But this is the complete opposite of my preferred state of being and I had to work at developing these skills. For instance, my idea of the perfect holiday is to show up somewhere new with nothing planned and see how it goes!

Q: Who or what inspires you?

A: Curious people inspire me the most. I have family, friends and colleagues who are endlessly curious about the world, from the state of politics and the economy to the newest high tech gadget. Their curiosity is infections, and I think having conversations on topics unrelated to my work helps me put it in a wider context, and hopefully ask better and more meaningful questions.

Q: How would you describe your speciality?

A: I’ve always been interested in trying to understand why we do the things we do. I’ve had multi-disciplinary training with an undergraduate in experimental psychology and computer science, a master’s degree in health promotion and a doctorate in public health. I’ve always focused on food and reducing the risk of chronic disease. But the disciplinary perspective and specific methods that I’ve applied to understanding this have varied a great deal -from psychology to sociology to epidemiology - growing my knowledge, skills and how I see the problem each time. Now with the start of this system level evaluation of the soft drinks industry levy, my horizons are about to expand further. It’s unclear to me if this is moving toward or away from developing a speciality! 

Q: So having looked at the same problem from various perspectives, why do you think it’s so difficult to eat a healthy diet?

A: As a trained psychologist I used to think we were in control of our behavior, but through my research I’ve realised that many things influence us to do things that don’t match up with our plans and goals. On the whole we know that we’re supposed to make choices that support our health, but the vast majority of the population isn’t able to do it. Why? Why don’t we eat the recommended amount of fruit and vegetables? Why do we tend to consume more than the recommended amounts of sugar? Individuals do not make their choices in a vacuum. We are influenced by many things, from family and friends, to our economic circumstances, the design of our communities, government policies, and the commercial food systems that shape the types and amount of foods available for entire populations. At first glance the problem may seem simple; the solution is anything but.


Read more about the Soft Drinks Industry Levy Evaluation 

Explore Great Snackington – where healthy food can be hard to find.