nosh magazine (issue 3) | Page 5

nosh magazine SHOULD YOU GO LOW CARB? Low carb diets have been around since the 1960s, with the best known approach being the Dr Atkins diet. It lost popularity to low fat diets over the last few decades, but as nations have continued to get fatter and the major flaws of going low fat have been exposed, the low carb approach is once again gaining momentum. Dr Joanna McMillan explores the question, “should you go low here are now several good clinical trials showing that the approach can be effective and safe, with some studies showing better results when compared to a low fat diet. But does that mean it’s the way we should all be going? I don’t believe so. Here’s why: T 1. The studies almost always compare low carb to low fat, but these are not the only options. Why not compare a low carb diet to one with moderate carbs and moderate fat, from good quality food sources? There are many ways to put together a healthy diet to help us to control our appetite and eat less, while still enjoying our food. My second question is what exactly is meant by “low fat”? We now understand that replacing fat with lots of refined carbohydrate (e.g. low fat cookies and ice cream) does not benefit our health. But a low fat diet based on whole foods (e.g. the traditional Japanese diet) and is likely to create a very different picture. Also, when you look closely at the data you’ll see some people did better on low fat, while others did better on low carb, which suggests something else is at play – genetics or perhaps personal food preferences that allowed better adherence to one diet or the other. 2. We have to look at what replaces the carbohydrate or the fat. Low carb diets usually have a high protein content, but also a high fat content. But where is the fat coming from? Is it high in saturated fats, or high in plant fats, which are mostly unsaturated? A low fat diet can also be high in protein, but keeps the good quality carb-rich foods in there too. All of these diets are very different and may have different effects on our health and weight control. Certainly many of the high protein diet studies actually have moderate amounts of carbohydrate, suggesting that the benefits are due to the extra protein rather than from avoiding carbs. 3. Going low carb can make it difficult to meet your fibre requirements. Wholegrains, legumes and fruit are also major contributors to fibre and without them you have to eat an awful lot of veggies, nuts and seeds to meet your daily target. You can do it if you’re very dedicated to packing your meals with veggies, but since only seven per cent of Aussies are managing to eat the recommended five serves a day, it’s a pretty big challenge to successfully eat more. Cereal fibre also seems to play a particular role in gut health, as does resistant starch found in beans, firm bananas and cooked and cooled potatoes, pasta and rice. This special type of fibre feeds the good bacteria in your gut, with many knock on health effects. Furthermore large population studies have shown that those who eat wholegrains tend to be leaner with smaller waist measurements. Lumping these “smart carbs” in with all carbcontaining foods is just nutritional nonsense. 4. Carbohydrates are the premium fuel for the brain and for powering exercise. The more intense the exercise, the more carbohydrate we need to use. Fat provides a slow steady stream of energy but cannot be burned quickly enough for more strenuous exercise.  Low carb diets can, therefore, make it very difficult to exercise at any intensity. You may also find your brain feels a little foggy and concentration is more difficult. Perhaps this abates if you stick with the plan and your brain adjusts to using ketone bodies – made from fat – but why deprive your brain of the fuel that works best? Of course, probably the most important point is that most people find low carb diets really difficult to stick to in the long run. And at the end of the day, regardless of how effective a diet is, if you can’t follow it for the long term it’s not going to do you much good. I certainly don’t dismiss this diet completely as it will be right for some of you, but for the majority I prefer a more balanced approach, based on quality food. N Dr Joanna McMillan, PhD APD Learn more about Dr Joanna at website | profile Adopted by the nation as an honorary Aussie, Dr Joanna McMillan’s ever-growing following is the result of her high profile within the media, health and fitness industries, and through her roles as Vice President of the Australian Lifestyle Medicine Association (ALMA), Ambassador for Diabetes Australia, and Ambassador for Australian Pineapples (to name a few). 5