Can you recommend the ketogenic diet?
Q: I keep hearing about a new diet called the ketogenic diet that’s good for weight loss. Just wondering if you could explain what it is and whether you support it? Thanks, Michael
A: The ketogenic diet – or ‘keto diet’ – is a high fat, very low carbohydrate diet. While it certainly has been gaining popularity recently, it’s actually not a new diet.
The classical ketogenic diet has been used since the early
1920s as an effective nonpharmacologic therapy for children with intractable epilepsy.
The classical ketogenic diet requires careful planning and monitoring to achieve a specific ratio of macronutrients (protein, fat and carbohydrates), with about 90 per cent of total energy (calories) coming from fat, and the remaining 10 per cent of energy (calories) from protein and carbohydrates combined.
This is vastly different from a typical Western diet, and leads the body to switch its main source of fuel from glucose (sugar) to fat.
This metabolic state is called ketosis.
It’s quite miraculous to think that by simply changing their diet, a person can experience a significant reduction in seizures (or in some cases, eliminate them), which can have a huge impact on their quality of life.
However, the restrictive nature of the diet means that supplementation is necessary to meet nutritional needs, and there are potential side effects, including fluid and electrolyte imbalances and digestive symptoms such as nausea and diarrhoea.
Over the past decade or so, a more relaxed ketogenic diet protocol – referred to as the Modified Atkins Diet in scientific literature – has been used with similar seizure reduction effects.
It differs from the classical ketogenic diet in that it does not restrict protein intake, although carbohydrate intake is still restricted to 10-20 grams per day. This protocol is similar to the ketogenic diet that has become popular of late, although the daily carbohydrate restriction for adults tends to be about 30 grams. To put into perspective just how low this is, a carrot (which isn’t considered a high carbohydrate food) would contribute a quarter of your daily carb intake.
There is preliminary evidence that the ketogenic diet may be beneficial for other health conditions (aside from epilepsy), however more research is needed.
From a weight loss perspective, the ketogenic diet has been shown to be effective among adults, with studies suggesting it may reduce insulin and appetite. However, we don’t know the long-term effects of following a ketogenic diet, and there are some concerns about how sustainable it is.
As the ketogenic diet tends to be lower in fibre, it’s also important to consider potential impacts on gut health – and we are discovering more and more about the importance of the gut microbiome to our overall health and also our weight.
It is not difficult for a diet to result in short-term weight loss – this is the case for most diets. However, more often than not, people who go on a weight loss diet for a period of time go on to regain the weight they lost, plus more.
There is no ‘‘one size fits all’’ approach to the way we eat, so if a ketogenic diet appeals to you, it’s important to consult a professional to ensure you are meeting your nutritional needs.
❚ Dr Libby is a nutritional biochemist, best-selling author and speaker. The advice contained in this column is not intended to be a substitute for direct, personalised advice from a health professional. See drlibby.com