6 29 vfi

Dietary Intake, Physical Activity and Body Weight

Although many people try to manage body weight in terms of calories in vs. calories out, a wide range of other variables impact human physiology.

The term “energy balance" is often thrown around when considering dietary intake, physical activity and body weight. While it seems that balancing two numbers (“calories in" versus “calories out") is a simple task, this may not be an entirely relevant way of looking at the situation.

Not all of the (chemical) energy that we consume is absorbed into the body and of that, not all may be utilised as an energy source (as the products of carbohydrate, protein and triglyceride digestion are also important building blocks for a number of other factors). The amount of energy exerted during physical activity is, outside of competitive athletes, a somewhat minor proportion of the energy we expend—or may not expend. The amount of chemical energy an individual may utilise to carry out the same amount of work is likely to differ between individuals. The best analogy I can think of relates to motor vehicles; while you can put the same amount of chemical energy (petrol) in a numbers of cars, the work that will allow (distance travelled) is dependent on the conditions and the brand of car. Imagine a situation where there are more than 7 billion brands of car and a divergent variety of (driving or energy-expending) conditions, and you can see the challenge with simply approaching the issue “calories in" versus “calories out." At an individual level, key goals to improve weight management should be increasing physical activity and/or decreasing energy intake. However, being too prescriptive over the amount of either of these changes may not have the desired effect.

In relation to this theme, my presentation at Vitafoods Asia 2016 will focus on a recent cross-sectional study of dietary intake and physical activity in children in Singapore. Available data on lifestyle and body fatness are extremely limited in this population group. Appropriate dietary intake and frequent physical activity are key elements associated with development in young children. I will present our summary data, share the challenges of collection of such information within young children and discuss the meaning of these study findings in a wider context.

Iain Brownlee, Ph.D., is a lecturer and director of operations for Newcastle University (Singapore) in food and human nutrition. He is a physiologist by training with particular interest in processes relating to the gut. Brownlee’s previous work has focused on all areas of the gut and has involved collaboration with pharmaceutical and food industry partners, as well as clinicians. He is particularly involved with food-based intervention studies, characterisation of how diet and lifestyle may impact health and wellbeing and the characterisation of health effects of bioactive, indigestible carbohydrates. Brownlee is an active member of the UK Nutrition Society and Singapore Institute of Food Science and Technology and has authored more than 30 original peer-reviewed articles, numerous book chapters and is an inventor on two international patents. He is also on the editorial board of the journals Bioactive Carbohydrates and Dietary Fibre and Food Hydrocolloids.

Hide comments


  • Allowed HTML tags: <em> <strong> <blockquote> <br> <p>

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.