The report by CSIRO, “Protein Balance: New concepts for protein in weight management”, said it has been established that higher protein diets boost fat loss but new research further suggests that protein at breakfast could reduce food cravings later in the day.
Senior principal research scientist for CSIRO, Professor Manny Noakes, said: “If you find it difficult to control what you eat, a redistribution of protein toward breakfast may be the answer to reducing your waistline without leaving you ravenously hungry and craving unhealthy foods.”
Furthermore, the report said recent science concludes that the body’s optimal protein requirements are higher than previously estimated, and scientific evidence supports eating at least 25g of protein at each main meal in order to control hunger as well as to enhance muscle metabolism.
“Higher protein diets that contain between 1.2g and 1.6g protein per kg of body weight per day and potentially include meal-specific protein quantities of at least ~ 25g protein per meal may provide optimal improvements in appetite, body weight management, and/or cardio-metabolic risk factors compared with lower protein high carbohydrate diets,” the report stated.
How protein helps weight loss
The report stated that higher protein diets may have a positive effect on weight management due to various factors including better appetite control, metabolic enhancement, reduced food cravings, biological drive for protein (Simpson and Raubenheimer), and improved body composition due to greater fat loss and less muscle loss.
Findings from recent studies include reductions in neural activation in brain regions controlling food motivation, reward, and cravings after high-protein over high-carbohydrate breakfast meals.
Moreover, according to the protein leverage hypothesis developed by Simpson and Raubenheimer, even small increases in the dietary percentage of protein at meals may have substantial effects on energy intake with an essential biological drive to achieve an adequate protein intake compared to carbohydrate and fat.
What this means is, all these factors help to “engineer” the body towards desiring a balanced amount of protein, while reducing the desire and cravings for fatty or unhealthy foods.
The report further highlighted, for most Australians, protein intake was skewed towards the evening meal, with only small amounts eaten at breakfast. Also, older Australians consumed the least amount of protein at breakfast but, in fact, need more protein to prevent muscle loss.
Australians also get over a third of their dietary protein from low-quality sources such as processed foods, instead of whole protein sources including lean meats, fish, eggs, legumes and dairy. Poor or imbalanced dietary choices lead to bigger health problems.
“Two in three Australian adults are either overweight or obese, which increases their risk factors for many chronic health conditions," said Prof Noakes.
Adopting a higher protein, moderate carbohydrate, low GI diet is a nutritious way to lose weight, and has been scientifically validated for some time, said the report.
In relation to exercise, the report stated: “There may be a diminished protein synthetic response to the ingestion of protein-dense food in overweight and obese adults compared with healthy-weight controls. This impaired response to protein is offset through resistance exercise with a balanced protein distribution.”
“The scientific evidence supports a higher protein diet, combined with regular exercise, for greater fat loss,” said Prof Noakes.