Primary researchers: Danielle Ferriday, Jeff Brunstrom (PI), Peter Rogers (Co-I), Matt Bosworth

Internal collaborators: Christina Potter, Natalie Evans

External collaborators: Laura Wilkinson (Swansea University), Ciarán Forde (National University of Singapore), Nathalie Martin (Nestlé Research Centre), Nicolas Godinot (Nestlé Research Centre), Katherine Appleton (Bournemouth University)

Background

In August 2012, the NBU started a BBSRC-LINK project exploring oral processing behaviours in humans. This project was funded by the BBSRC and Nestlé Research Centre.

This work builds directly on our previous BBSRC-DRINC project (round 1) in which we demonstrated the importance of consumer expectations in the selection of portion sizes. As part of this DRINC project we developed a ‘consumer expectations toolbox.’ This has since been used and adapted by several industry partners to understand and quantify consumer responses to the satiating effects of commercially available foods.

Our DRINC project also provided much of the methodological and scientific justification for this follow-on LINK project in which we are exploring the potential for translation of outputs from our DRINC project to address a specific and commercially relevant research question.

Overview 

For a long time, researchers and health professionals have suspected that obesity is associated with a particular eating style (i.e., eating quickly). Indeed, it is sometimes said that we should chew our food several times in order to feel satisfied and to 'aid digestion.' Recently, researchers have begun to explore this idea systematically. The results are striking. For example, under controlled conditions, it would seem that eating at a slower rate produces a reduction in meal size. Moreover, when we look at people across an entire country, we find that eating rate is a good predictor of body weight. In 2010 another group (also based in Bristol) started to look at whether it might be possible to reduce eating rate, and whether this might affect bodyweight. They used device called a mandometer to encourage adolescents to eat at a slower rate. This training produced a clinically significant reduction in bodyweight, which was sustained 12 months after treatment.

The prospect that we can manipulate eating behaviour to reduce energy intake is exciting because this approach has potential as an effective treatment for obesity. Moreover, an opportunity exists to change our eating behaviour by manipulating the physical characteristics of food. If this can be achieved then we may be able to design foods to encourage behaviours (i.e., slow eating) that reduce our calorie intake from meal to meal. Importantly, for these benefits to be realised, we need to discover the underlying mechanism. This is one of the main objectives of this project.

In the first phase of this project, we developed a method to quantify and characterise “eating topography” - collectively, the pattern of behaviours associated with eating; eating rate, oral sensory exposure time, chews per mouthful and so on. This was achieved using a novel combination of video recordings of mouth movements and real-time measures of plate weight via a hidden balance scale set into a table (see photos below).

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In our first two experiments, we explored whether it is possible to increase post-meal fullness and reduce meal size, simply by capitalizing on natural variation in the oral processing of commercially available pre-packaged meals (Ferriday et al., 2016). Across 20 commercially available pre-packaged meals, we found that foods that were eaten slowly delivered more satiation and satiety, and had a higher expected fullness. We also found that natural variations in the oral processing of pre-packaged meals reduced meal size. These differences in food intake during the ad libitum meal were not compensated at a subsequent snacking opportunity one hour later. Based on all of these findings, we concluded that altering food form to encourage increased oral processing might represent a viable target for food manufacturers to help nudge consumers to manage their weight.

We have also completed other experiments exploring the prospect that beliefs about the satiating quality of a food and visual cues of portion size can have a direct effect on how we eat a food. In a recent study we showed that eating rate is modified by visual feedback associated with the perceived rate of change in food volume during a meal. We are the first group to expose this implicit process. This work suggests that eating rate is not determined solely by the structural properties of food being eaten (Wilkinson, Ferriday, et al., 2016).

In the second phase of our project we completed a set of experiments where we focussed on the mechanism underlying effects of eating topography on energy intake. Two hypotheses were tested. First, we explored the prospect that a causal relationship exists between specific aspects of eating topography and the hunger and fullness that we experience at the end of a meal and during the period between meals. There are two reasons why this relationship might exist. Eating topography may change levels of hormones that control our appetite. Alternatively, it may influence the formation of memory for a meal - a process that is known to influence the amount of food that we eat at a subsequent meal (Ferriday et al., 2015). Our second hypothesis relates to the eating topography that is associated with particular foods. If a food is eaten with a topography that makes us feel full then we may remember this relationship. In future, when we encounter that food again, we may expect the food to be more filling and select a smaller portion. By this account, eating topography influences our energy intake by changing the way we make decisions about portion size, before a meal begins (Ferriday et al., In preparation).

Recent peer-reviewed papers:

• Ferriday, D., Bosworth, M. L., Godinot, N., Martin, N., Forde, C. G., Van Den Heuvel, E., Appleton, S.L., Mercer Moss, F.J., Rogers, P.J & Brunstrom, J. M. (2016). Variation in the Oral Processing of Everyday Meals Is Associated with Fullness and Meal Size; A Potential Nudge to Reduce Energy Intake?. Nutrients, 8(5), 315. Click here to view
• Wilkinson, L.L., Ferriday, D., Bosworth, M.L., Godinot, N., Martin, N., Rogers, P.J., Brunstrom, J.M. (2016) Keeping pace with your eating: Visual feedback affects eating rate in humans. PLOS ONE, vol 11(2), pp. e0147603. Click here to view
• Ferriday, D., Bosworth, M.L., Lai, S., Godinot, N., Martin, N., Martin, A.A., Rogers, P.J., Brunstrom, J.M. (2015) Effects of eating rate on satiety: A role for episodic memory? Physiology and Behavior, vol 152(Pt B), pp.389-396. Click here to view
• Forde, C.G., Almiron-Roig, E., Brunstrom, J.M. (2015) Expected satiety: Application to weight management and understanding energy selection in humans. Current Obesity Reports, vol 4, pp. 131-140. Click here to view

Recent peer-reviewed abstracts:

• Bosworth, M.L., Ferriday, D., Godinot, N., Martin, N., Campman, H.K., Lai, S.H.S., Rogers, P.J., Brunstrom, J.M. (2014) Effects of product labelling on eating topography, satiation and satiety. Appetite, vol 83, pp. 345. Click here to view
• Potter, C., Ferriday, D., Griggs, R.L., Hamilton-Shield, J.P., Byrom, O.S., Rogers, P.J., Brunstrom, J.M. (2014) Portion size selection and snack food preferences; inter-relationships between parent and child BMI. Appetite, vol 83, pp. 349. Click here to view
• Ferriday, D., Forde, C.G., Martin, N., Hamill, L.R., Bosworth, M.L., Miles-Wilson, J.J., Rogers, P.J., Brunstrom, J.M. (2013) Exploring relationships between expected satiation, eating topography and actual satiety across a range of meals. Appetite, vol 71, pp. 474. Click here to view

Other coverage of our work:

• Coverage of Ferriday et al. 2015 article - http://www.dailymail.co.uk/sciencetech/article-3171487/Mother-right-Scientists-secret-feeling-fuller-longer-eat-slowly.html