The low carb diet – myths and facts

As nutritional science continues to evolve, separating fact from fad can be tricky. But one healthy eating plan that has stood the test of time and science is The CSIRO Low-Carb Diet.

This approach to a healthy diet is the focus of Associate Professor Grant Brinkworth and Senior Research Dietitian Pennie Taylor’s latest book, The CSIRO Low-Carb Diet. Here, Grant shares some essential knowledge on the science of weight loss and eating well.

People often think a low-carb diet means no bread - myth or fact?

Some diets out there severely restrict, or entirely ban, the eating of all carbohydrate-rich foods. This is not conducive with a balanced diet.

The CSIRO Low-Carb Diet limits carbohydrate-rich foods, but this doesn't mean no carbs at all. The diet plan allows some low-glycemic index and high-fibre carbohydrate foods such as wholemeal, multigrain or fruit bread.

A low-carb diet also includes dairy foods and liberal amounts of low and moderate carbohydrate vegetables such as all of your green leafy vegetables.

The CSIRO Low-Carb Diet is also high in protein. This includes foods such as lean meat, fish, poultry, eggs and tofu, and healthy fats like avocados, nuts, seeds, and oils including olive, canola, sunflower and sesame oils.

"The CSIRO Low-Carb Diet limits carbohydrate-rich foods, but this doesn't mean no carbs at all. The diet plan allows some low-glycemic index and high-fibre carbohydrate foods such as wholemeal, multigrain or fruit bread."

The CSIRO Low-Carb diet is based on a large, comprehensive Australian study. Can you describe the study and its key findings?

Two groups of a total of 115 adults who were overweight or obese and had type 2 diabetes were randomly assigned to consume one of two diets – an energy-reduced, low-carbohydrate, higher protein, and high healthy fat (i.e. the CSIRO Low-Carb Diet); or a traditional, energy reduced, high unrefined, carbohydrate, low-fat diet. Both groups also participated in a program of 60 minutes of exercise three times a week.

While both groups experienced health benefits, individuals following the CSIRO Low-Carb Diet also reduced their diabetes medication by an average of 40%. The low-carb approach resulted in greater health improvements and helped to normalise blood cholesterol and glucose levels to a much greater extent.

Compared to the traditional high-carb, low-fat diet, the low-carb diet had a 2-3 times greater reduction in the levels of blood glucose spikes and fluctuations throughout the day.

How does the diet improve metabolic health?

The CSIRO Low-Carb Diet improves metabolic health by sustaining weight loss over the long term. The other main benefits to metabolic health include:

• Decreasing blood glucose levels after meals, as well as blood glucose fluctuations.
• Improving the blood-cholesterol profile by reducing the levels of triglycerides and LDL (‘bad’) cholesterol and increasing the levels of HDL (‘good’) cholesterol.
• Reducing the amount of diabetes (blood glucose-controlling) medications needed.

Who would benefit most from a low-carb diet?

The diet is highly recommended for individuals who are overweight or obese, and/or have type 2 diabetes, metabolic syndrome or insulin resistance. It would also greatly benefit people who have risk factors for type 2 diabetes or heart disease such as high waist circumference, high blood pressure, high fasting blood glucose levels and high blood cholesterol levels. This represents a high proportion of the Australian adult population.

The CSIRO Low-Carb Diet by Associate Professor Grant Brinkworth and Pennie Taylor is available now from Macmillan Australia, RRP $34.99.