Spotlight on Associate Professor Leonie Heilbronn

Associate Professor Leonie Heilbronn and her team now have $987,047 to look into intermittent fasting as a nutritional strategy for managing obesity and its effects on metabolic health and weight in people with pre-diabetes. We talked to her about her work and what inspired it.

Tell us more about your study

We have known since the 1940s that calorie restriction (CR) not only improves health span, but also increases maximal lifespan in many animal models. More recent evidence says intermittent fasting can also increase maximal lifespan. In our study, we will be recruiting 200+ people who are at high risk of type 2 diabetes to take part in a two-year study. We will be comparing different modes of dieting—daily and intermittently—to determine which diet will make people the healthiest.

If you are overweight and want to take part, please get in contact with us! This study will start in March 2018.

Why is this study important?

Overweight affects around two thirds of the adult population in Australia and obesity increases the risk of more than 50 diseases, including heart disease, diabetes and cancer. 
But losing weight and maintaining weight loss is very difficult due to body’s physiological defence mechanisms to protect against loss of fat. We are interested in studying different approaches to improving health.

Our short term data shows that intermittent fasting produces slightly greater weight loss and better improvements in diabetes and cardiovascular health outcomes. We are now testing whether intermittent energy restriction has similar effects longer term in individuals who are at risk of developing type 2 diabetes.

Has any significant work led to this study?

My postdoctoral supervisor and I were the first to study alternate day fasting in humans back in 2005, and since then many human studies have been investigating the legitimacy of this diet approach. But still very few randomised control trials (RCTs) have been conducted—and only one study has operated over 12 months. This study will be the first to compare the long-term effectiveness in this target group.

Tell us about your team

The team includes post-doc Amy Hutchison, who was involved on the short-term study on intermittent fasting that was recently completed, and Bo Liu, who is fantastic in the lab. We are working again with Professor Gary Wittert, who is an endocrinologist and obesity expert. This year we welcome Manny Noakes from CSIRO, who I worked with back when I was doing my PhD and who has many years of experience in diet interventions in this target population. Collaborating with us for the first time on this work is Professor Christine Feinle-Bisset, who has a strong appetite regulation background—which is a second aim of this study.

What inspired you to pursue this research?

I have a life-long interest in healthy eating and living—most of the time! Enjoying yourself is also an important balance. There is a joke around the calorie restriction field that CR doesn’t actually make you live longer… it just makes you feel like you have.

What’s one thing you wish all people knew about nutrition or obesity?

When you lose weight your body alters secretion of appetite regulatory hormones that make you hungry! And at the same time, your body will adapt to the calorie restriction to reduce metabolic rate—meaning that as you lose weight you need even less food that you did before. These adaptations make long-term weight loss very difficult. It is not a lack of “will power” that leads to weight re-gain, it is a physiological process.

What’s your go-to healthy food?

Carrots! Delicious and easy to eat on the go. With three kids in my household we go through a few bags a week!

What’s your go-to nutrition fun fact about yourself?

I only drink water and wine! Everything else is just empty calories.