The debate around whether low-carb diets are good for you has fired up again following a new study, writes diabetes educator LINDA BRADBURY.

A recent study by Monash and RMIT Universities has captured a lot of attention, especially due to its initial claim suggesting low-carb diets may increase the risk of type 2 diabetes. This has sparked fierce debate from those who support low-carb diets and those who are wary. Supporters of a low-carb eating style quickly attempted to discredit the study, emphasising its limitations and asserting that low-carb diets offer endless solutions to modern health issues. On the other side of the fence, more conservative health professionals celebrated the findings, believing it confirmed their long-standing doubts about low-carb diets as a sustainable approach for managing type 2 diabetes.

Which side is right? Rather than choose sides, let’s take a step back and objectively look at the research and the broader debate.

The history of low-carb diets

Low-carb diets are not a new idea in diabetes management. In fact, they have been used as a treatment for diabetes for centuries, long before the discovery and development of medical interventions such as insulin. Low-carb diets surged in popularity between the 1970s and 90s, including the Atkins diet, the cabbage soup diet, and, more recently, the paleo diet. Although their popularity has ebbed and flowed, they remain a fixed and visible dietary option, promoted by a band of passionate followers.

While definitions vary, a low-carb diet typically means eating less than 130g of carbohydrates per day or limiting carbs to less than 26% of your total energy intake. Very low-carb diets, which you might hear about as ketogenic (or “keto”) diets, restrict carbs to under 50g per day or less than 10% of your total energy intake. It is important to highlight that keto diets are not being considered or discussed in the research in question or this article.

So what have we learned from the Monash study?

The short answer is: not much. While the media has jumped on the idea that a longstanding approach to health and diabetes management might actually be bad for you, it’s not an idea that is really borne out by the study’s findings. If we’re wanting to consider what the study actually tells us about low-carb diets, it’s worth bearing a few things in mind.

Firstly, true low-carb diets weren’t tested: The research compared high-carb diets (55% of total daily energy) with a moderate-carb diet (38% of daily energy), which it assigned as the “lower” carbohydrate diet. As it did not examine true “real world” low-carb diets (less than 26% energy from carbs), it makes it difficult to draw conclusions about their effects on type 2 diabetes risk.

The main conclusion is also misleading: Once researchers accounted for participants’ weight, height, and waist circumference, there was no statistically significant connection between “low” carb intake and increased type 2 diabetes risk. The suggestion that low-carb diets might lead to higher BMI through increased fat intake lacks concrete evidence and is only speculation.

The data collection also looks very limited. The study relied on food frequency questionnaires, which are prone to errors, as they depend on participants accurately reporting their dietary habits. Given the study’s long-term nature, the quality of the data is questionable.

Keeping perspective: what does this all mean?

Despite the concerns listed above, we need not wholeheartedly embrace low-carb diets as the best or only dietary solution in type 2 diabetes. The ongoing debate about low-carb and high-carb diets misses a key point, which is that the quality of what you’re eating is as important as its carb content.

The rush to paint the debate in black-and-white terms makes it difficult to consider the evidence. Research that pits low-carb diets against high-carb diets is often reductionist, ignoring the broader context of diet quality and lifestyle factors. This overly simple framing of the issue makes it easier to market diets and sell products, but does little to advance our understanding of what it truly means to eat a healthy diet. Rather than focusing strictly on carbohydrate intake, we should be paying attention to the underlying quality. Important factors may include:

• Carbohydrate quality: Prioritising low glycaemic index (GI) foods and unprocessed carbs, while minimising added sugars.
• Nutrient diversity: Getting a wide variety of vitamins and minerals from vegetables, legumes, and whole grains, with a strong emphasis on fibre.
• Limiting unhealthy fats: Reducing processed saturated fats and avoiding excessive intake of processed foods.
• Limiting excess energy intake: Considering that energy comes from all macronutrients (fat, protein, and carbohydrates).
• Reducing alcohol intake.

The ongoing debate about low-carb and high-carb diets misses a key point: that the quality of what you’re eating is as important as its carb content.

The binary trap

The real question may not be how much carbohydrate we should consume, but whether we are framing the debate correctly. The human body is incredibly adaptable, as demonstrated by the stark differences in dietary patterns between cultures like the Inuit people (who traditionally eat very few carbs) and the Okinawans (whose diet is high in carbs). This suggests that there may be no single “right” answer to the ideal carb intake.

Conclusion

While the low-carb movement has had its controversies, there are reasonable grounds to believe that a high-quality diet may be healthy, regardless of whether it’s low or high in carbohydrates. This assumes we factor in considerations such as food security, socio-economic status, patient profiles and medical history, cultural values, or disordered eating risk. Once we’ve agreed many different dietary patterns might lead to good health, the work and research can then focus on what those puzzle pieces actually are.