Protein key to obesity epidemic?

University of Sydney research suggests that protein could be key to the obesity epidemic. According to the research, our instinctive appetite for protein is so powerful that it drives us to continue eating until we have sufficient protein - even if it means consuming far more energy than we need.

Published in the journal Obesity Reviews, the research shows the overriding drive for dietary protein could be a key factor in the global obesity epidemic, with an inverse relationship noted between the percentage of protein in an individual’s diet and their total energy intake.

Regardless of weight, age or the time frame of a diet, the research found that reducing the percentage of dietary protein will result in increased total energy intake, contributing to overweight and obesity.

“We found that regardless of your age or BMI, your appetite for protein is so strong that you will keep eating until you get enough protein, which could mean you’re eating much more than you should,” said Dr Alison Gosby, lead author of the research and a Postdoctoral Fellow at the University of Sydney’s Charles Perkins Centre.

“For example, when you consume things like soft drinks, which are fairly low in proportion of protein but high in calories, your energy intake will increase because you’ll need to keep eating to get the protein you need. If you add a soft drink to your lunch then you’ve added a lot of calories, but you’ll still have to eat the same amount of food.

“The strength of our nutritional drive for protein is frightening within our nutritional environment, where there are a large number of low-protein foods consumed on a regular basis.”

However, Dr Gosby doesn’t recommend people increase their protein intake as most people consume enough protein, but eat too much in order to get it. She says the increased understanding of appetite provided by her research could have profound impacts on the design of effective and healthy weight-loss diets, food labelling policies, food production systems and regulatory frameworks.

“We have shown that when people are trying to lose weight they need to look at macronutrient composition, not just calories. If you cut out calories but don’t consider protein intake, you’re going to be hungry and your diet won’t be successful,” Dr Gosby said.

“We do not advocate a high-protein diet, which we generally find to be unsustainable, but instead urge people to follow a balanced diet and eat healthily. Preparing your own meals, rather than relying on energy-dense, low-protein processed foods, could make an enormous difference to the amount of food you need to consume.”

The research examined the results of 38 published experimental trails measuring the unrestricted energy intake of people on different diets, also taking into account a broad spectrum of age ranges, body mass indexes (BMIs) and diet durations.