THE next time you're trying to lose a few pesky pounds, consider reaching for a tub of yoghurt, a glass of milk and a few slices of cheese.
Curtin researcher Dr Wendy Chan She Ping Delfos has uncovered some interesting weight loss effects as a result of increasing a person's daily recommended dairy intake.
Her research found that upping dairy to five serves a day (from the Australian dietary guidelines recommendation of three serves), can lead to increased weight loss when coupled with a calorie-reduced diet.
One serve of dairy is 250mL of low-fat milk, 200g of full-fat yoghurt or 40g (about 2 slices) of full-fat cheese.
Her PhD thesis, which was funded by the ATN Centre for Metabolic Fitness and Diabetes Australia, was based on historical research on the health benefits of dairy proteins.
"Dairy proteins are considered to be good proteins that contain lots of amino acids", Dr Chan She Ping Delfos says.
When she was formulating her hypothesis, there was talk of increasing the recommended daily number of serves of dairy for Australians, so Dr Chan She Ping Delfos and her supervisor, Associate Professor Mario Soares, took this one step further and designed a study to test the potential benefits.
For weight loss to occur, it's pivotal that a person uses more calories during the day than he or she consumes. Hence, according to Dr Chan She Ping Delfos, "each person in the study consumed only 75 percent of his or her total recommended daily intake".
To do this, participants' metabolic rates were measured and the intake of fats, proteins and carbohydrates was then tailored for each person.
Individuals were assigned to consume three or five serves of dairy per day while keeping to the 75 percent intake threshold.
Dr Chan She Ping Delfos's study revealed that the "five servers" had higher mean levels of both weight loss and fat-mass loss, a greater drop in systolic blood pressure, and a greater total percentage of abdominal fat loss when compared to the "three servers".
Another branch of the study further divided the "five servers" into two subgroups - one that took regular resistance exercise and the other subgroup that did not.
In both subgroups, the average mean weight loss was 8kg over three months, but the participants that exercised had better overall fitness, which was shown by less muscle loss and a higher rate of fat burning than the non-exercisers. In addition, at the 12 week follow up, those that exercised had a lower percentage of total fat regain.
"Increasing dairy intake to five serves per day as part of a reduced calorie diet has never been studied before," Dr Chan She Ping Delfos says.
"We think that consuming the good dairy proteins along with calcium and vitamin D (which helps to absorb calcium into the body) helps to increase weight loss."
The effects on health are even more prevalent when coupled with a resistance exercise program.
Dr Chan She-Ping Delfos received a Curtin University Postgraduate Scholarship award for this work, and is now a post-doctoral fellow at the Curtin Health Innovation Research Institute, where she will continue to focus on ways to fight obesity.