Our low-carb diet: scientifically proven and not a passing fad

By Asaesja Young

Low-carb isn’t a new concept. In fact, it’s been around for so long that people might have forgotten about it. But in a world full of nutrition noise, few diets have undergone the type of rigorous testing and research which still hold true.

With so many variations and options out there, we’re providing a science-based insight into the world of eating low-carb.

You have (low-carb diet) questions, we have answers

What is ‘low-carb’?

Low-carb is often defined as a diet providing less than 130 grams of total carbohydrates per day. In our CSIRO Low-Carb Diet, we’ve classified it as 50-70 grams of good quality unrefined, low glycaemic index (GI) carbohydrates. This is compared to the average Australian eating 225 grams per day (Australian Bureau of Statistics).

In a low-carb diet, approximately 10-14 per cent of your total energy intake each day comes from carbs and 58 per cent from healthy fats. We also use a higher protein approach across our meals, reaching 25-30 per cent of your total energy needs for the day. They’re a lot of numbers, but essentially it is a low-carb, high protein and healthy fat plan.

Aren’t fats bad for me?

Since the ’70s many of us have been told a low fat, high-carb, low protein diet is best. So you would be forgiven for thinking fats are bad. But over time, research has shown that all fats aren’t equal. Eating foods high in good fats, like avocado, nuts, olive oil and fish, can help reduce your risk of heart disease. Replacing carbohydrates with higher levels of good fat in your meals and diet can also help to improve blood glucose control (blood sugar, defined in the next question) and reduce the level of blood glucose spikes after eating.

Why are too many carbs or sugars bad for me?

The lower amounts of carbs and higher amounts of proteins and healthy fats in the CSIRO Low-Carb Diet helps the system by reducing these big increases in glucose levels so the system doesn’t have to work as hard. People with type 2 diabetes could see a reduction in their blood glucose levels.

How does a higher amount of protein help me?

Part of the reason low-carb diets are effective at helping you lose weight is increasing the amount of protein you eat. This helps control cravings and suppress your appetite. Eating higher amounts of protein also helps to maintain your muscle mass, which gets your metabolism burning more calories. Just like fats, replacing carbohydrates with higher levels of protein in your diet can also help to improve blood glucose control and reduce the level of blood glucose spikes after eating.

Do I still have to exercise?

Ideally exercise combined with the nutrition plan is best. Research shows that the level of physical activity you engage in each week is one of the strongest predictors of losing weight and keeping it off. Exercise can also improve your blood glucose control and health and wellbeing, whether you lose weight or not. But if you can’t exercise, the nutrition plan by itself can still make a big difference.

So, what’s the science behind it? Why should you go low-carb?

In 2012 we began one of the most significant clinical trials on low-carb and its effectiveness for weight loss and management of type 2 diabetes. The study ran for two years and included one group of people who were given the CSIRO Low-Carb diet, and another group who were given a more traditional high carbohydrate, low protein, low fat diet that had the same amount of calories. All participants had type 2 diabetes and were either overweight or obese adults. Both groups also participated in the same amount and type of exercise (60 minutes of aerobic and weight training, three times a week).

Year one results

Both groups benefitted from reductions in body fat, blood pressure and blood glucose, and improved their quality of life and mood. However, there were striking differences in several important areas.

The low-carb group saw a reduction in their diabetes medication that was twice as large as the high-carb group. The low-carb group also saw an improvement in their glycaemic stability – the peaks and troughs in blood glucose levels across the day being balanced – by three times compared to the high-carb group. This means greater improvements in blood glucose control and reduced risk of health complications associated with diabetes. The low-carb group also had a larger improvement in good fats (High Density Lipoprotein or HDL for short), and a greater reduction in bad ones (Low Density Lipoprotein LDL). This means a greater reduction in the risk of heart disease.

Health measure Average change in the Low-Carb Diet group Average change in the high-carb group Diabetes medication needs -40% -20% Glycaemic variability (high and

low glucose levels) -30% -10% Blood triglycerides (bad fats, in millimoles) -0.4 mmol/L -0.01 mmol/L HDL cholesterol (good fats, in millimoles) +0.1 mmol/L +0.06 mmol/L

Credit: CSIRO Low-Carb Diet Quick and Easy

Year two results

After two years on the assigned diets, the health outcomes remained on par with the results at year one. This showed the low-carb diet was a sustainable and long-term option for weight loss, diabetes control and health improvement

Translating years of research from the lab to the public

After years of research and clinical trials on low-carb eating and its effectiveness for weight loss and the management of type 2 diabetes, we released the first CSIRO Low-Carb Diet in 2017. Following the success of book one, we published book two in 2018 with 80 extra everyday low-carb recipes.

Our third book in the series: The CSIRO Low-Carb Diet Quick and Easy, will be in stores from 24 September. In this edition, we provide an update on the science behind low-carb, including new research on the health benefits of a low-carb diet coupled with exercise. Designed with a busy lifestyle in mind, the new recipes can be prepared in 30 minutes or less with under 10 ingredients.

We’ve also incorporated some easy to grab and go pre-packed supermarket products into the recipes to make mealtime even simpler. If you’re interested in getting a copy, you can order online.