|Volume 11 Issue 1 | www.gilabs.com | Winter 2017|
Dr. Nick Bellissimo
This month, we interviewed Dr. Nick Bellissimo, Associate Professor in the School of Nutrition at Ryerson University, whose research specializes in appetite and energy imbalances in children.
What are some of the factors that contribute to overeating and obesity in children?
Where do we begin? One of the things we know is that over the last 40 years, we have moved away from traditional foods to highly processed foods which may or may not be as satiating as other foods that were previously available. In kids, the picture is quite complex and many factors interact to determine a child's growth trajectory, including screen-time exposure, physical activity and snacking. Our goal is to understand how diet, exercise and environment interact to shape a child's eating behaviors and body weight.
What are some of the strategies you are researching to address overeating and obesity in children?
We examine both energy intake and expenditure. For energy intake, we study how the macronutrient composition of a meal or snack affects appetite, food intake suppression and metabolic profiles in children. Our goal is to understand how meals and snacks can be redesigned to tide people over to their next meal so that they are less likely to reach for less satiating snacks that are high in calories and poor in nutrients. We can also monitor the effects of meal composition on resting metabolism and basal metabolic rate, using indirect calorimetry. We also routinely determine how meal composition affects the thermic effect of food (energy required to digest and process food). We can also measure non-exercise activity thermogenesis, which is heat production from daily movement using research grade accelerometers in free-living conditions.
One thing we see is that if you change one component on one side of the equation, there is often (within days or weeks) compensation on the other side of the equation. For example, if you are trying to lose weight and you exercise more, your body often adjusts by eating more. We try to look at the overall picture and investigate if there is a way to manipulate the physiological systems and the regulatory pathways to impact eating behaviours to promote the achievement or maintenance of healthier body weights. From a food science perspective, we often use reverse engineering to understand why some food and food components are more satiating than other. We then use this information to develop new and improved food products to enhance satiety or control excursion in blood glucose.
What types of specialized equipment do you use in your metabolic research?
- We have developed a rapid in vitro digestion model that strongly predicts postprandial glycemic response, called the DRUID (Ryerson University in vitro Digester) -
- We have the Bod Pod, for measuring body composition using the same principles as underwater weighing, but using air displacement.
- We have the FIT 3D, which assesses all circumference body measures using phototechnology, in the span of about 30 seconds
- We use indirect calorimetery to measure energy expenditure at rest, during exercise, and in response to meal digestion and processing.
- We have an exercise physiology unit, where we can perform time trials to assess the effect of food and food components on exercise performance, in addition to assessing aerobic fitness.
- In 2017, we are expanding our research program to include a suite of food science tools and instruments to monitor food digestion in vitro, as well as new tools to monitor physiological hormones in vivo.
In research performed at GI Labs examining a randomized, cross-over study of 38 healthy subjects, Dr. Thomas Wolever, Dr. Alexandra Jenkins, and colleagues demonstrate that oatmeal elicits significantly lower glycemic responses than matched servings of Cream of Rice, even when sugar was added to the oatmeal, demonstrating that oatmeal minimizes postprandial glycemia.
A meta-analysis published by GI Labs President Dr. Thomas Wolever and colleagues demonstrated that Glycemic Index values do not differ when measured in Caucasians versus non-Caucasians. Reviewing 1288 trials validated that, with the possible exception of rice, GI values remain consistent across people with different ethnicities.
In research performed at GI Labs, Dr. Thomas Wolever and colleagues investigated whether oat β-glucan mixed in water and consumed before a meal would have an effect on postprandial glucose levels. Previous studies suggested that viscous fibers may need to be taken with the meal in order to have a lowering effect on glucose levels. The results of the study demonstrate that oat bran can be used as an effective preload to consume before a meal in order to manage postprandial glucose levels..
Research from the University of Sussex demonstrated that when certain odours were associated with creamy and thick foods (which are expected to be satiating), those odours themselves became associated with satiety and feelings of fullness. This finding holds potential for the development of weight-loss products or other products that promote satiety.
With more than half of Americans partaking in regular exercise and with exercise a first choice option in disease prevention, consumer interest in sports nutrition products is growing. Key priorities for consumers include foods that are easy to consume on the go, products that promote recovery post-exercise, and products that provide long-lasting energy and endurance.
According to a recent survey of 7000 people across Europe, the Middle East, and Africa, almost half of the respondents (45%) were worried about getting the right amount of nutrition.
Weight is the top concern among adults aged 18-50. Respondents in Italy, France and Egypt are most concerned about protecting themselves against disease later in life.
According to recent market research data from the Hartman Group, consumers associate high quality food and beverages with better nutrition, further reinforcing the connection between "premium" and "healthy" in food products.
April 22-26, 2017
MCCORMICK PLACE CONVENTION CENTER, CHICAGO, IL
Dr. Thomas Wolever, President of GI Labs, and Dr. Alexandra Jenkins, Director of Research, will be attending as well as presenting their research.
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Institute of Food Technologists Annual Meeting + Food Expo
June 26-28, 2017
SANDS EXPO CENTER, LAS VEGAS, NV
GI Labs will once again be exhibiting at this major event for the food industry. Come visit us at booth #4564!
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