Low Carb Diets: Everything You Need to Know
Low carb diets are as popular as ever. However, despite this continued upward trend, there are still a lot of myths surrounding low carb eating. In this post, we’re going to discuss the different types of low carb dieting, when and where they might be useful and hopefully help you cut through some of the misinformation that surrounds this method of eating.
WHAT IS A LOW CARB DIET?
There are several different types of low carb diet, but one thing you must consider is what ‘low carb’ actually means to you. For example, someone who has a sedentary job, uses little energy and exercises infrequently will need to consume less calories to maintain or lose weight compared to someone who is highly active. This means for a sedentary person, even a ‘normal’ carb intake – as a proportion of their overall daily calorie requirements – might be considered ‘low’ compared to other more active people.
Conversely, if you have an athlete training multiple times a day at intensities that require carbs as a primary fuel source, even hundreds of grams of carbohydrates a day might be considered low for their needs. In this regard, low carb is at some level relative to an individual’s total daily energy needs, the type of activity they undertake and their overall goals. There are however diets considered to be low carb in any context and these ‘very low carb’ diets typically aim for less than 50g of carbohydrates per day.
The most popular low carb diet at the moment is the ketogenic Keto Diet, which advocates a very low amount of carbs – limiting their intake almost completely – and instead, focuses on harnessing energy from protein and fats. The composition of Keto Diet is around 30% of calories from protein, 60% from fats and less than 10% of calories from carbs.
The aim of this diet is to move your body into nutritional ketosis. In this state, your body is depleted of carbs (the normal fuel for your brain) to the point where it needs to ‘switch’ to producing ketone bodies from fats. Ketone bodies are important because they can provide fuel for your brain, whereas fatty acids in their normal state cannot pass the ‘blood brain barrier’ to provide energy.
Keto diets were originally developed to help with some medical conditions such as epilepsy. Being in ketosis has the potential to reduce fitting episodes, but for those who do not have a medical condition, it’s important to note ketosis does not offer magical weight loss benefits.
HOW DO LOW CARB DIETS WORK?
These diets work simply by restricting the amount of energy you consume in a way that doesn’t (necessarily) require you to track calories – although calories do still very much matter! Many keto ‘zealots’ claim hormones – primarily insulin – are responsible for weight gain and preventing weight loss. They claim because these hormones are released as a response to consuming carbs, it’s carbohydrates that are responsible for weight gain – not people consuming too many calories.
This is simply not the case. Several studies have shown when protein is matched it really does not matter where you get the rest of our calories from – be that carbs or fats. For weight loss, you must be calorie deficit and consistently burning more calories than you consume.
That’s not to say low carb or ketogenic dieting might not have some advantages…
WHAT ARE THE ADVANTAGES OF LOW CARB DIETS?
Low carb diets can be an effective weight loss solution for two primary reasons. Firstly, they encourage people to eat more protein. Protein is important because not only does it help preserve muscle tissue when dieting but it’s also the most filling nutrient, which helps control hunger and cravings.
Secondly, by removing carbohydrates the diet removes many foods people are prone to overeat – reducing calorie intake and creating weight loss as a result. Removing foods containing starchy carbohydrates and sugars is likely to rule out a whole host of foods that are calorie dense like pizza, bread, chips, pastries, chocolate, sweets and ice cream to name but a few. This is going to drastically help reduce opportunities to overeat and will help put the body in a calorie deficit to lose weight.
DO LOW CARB DIETS REQUIRE SPECIAL CONSIDERATIONS?
For those who go very low carb, there is usually a period of brain fog until your body adapts to using dietary fat more efficiently as a fuel. It may also be wise for those who take part in competitive sport – especially those with high intensity ‘anaerobic’ bursts of energy – to avoid very low carb dieting because carbs, either from food or stored as glycogen in your body, is the only nutrient that can provide energy during exercise at high intensity.
Removing carbohydrates, especially fruits and vegetables, can mean the diet has a lack of essential vitamins, minerals and fibre, which may require supplementation. This also includes electrolytes which are important for normal function. So supplements may be important depending on the degree of carb restriction you follow.
Low carb dieting appears to be effective in the short term, but long term restriction of certain foods means many people struggle with adherence and it may have some other knock on health implications which might need serious consideration. Once people come ‘off’ the diet, they tend to regain weight quickly, believing carbs are the problem, when in fact it they’re simply consuming too many calories for their needs again. There’s often a ‘water rebound’ too, which is caused by carbs being stored in the muscles and liver as glycogen. This also acts to hold more water and increase weight rapidly. This can create the illusion that carbs are in fact the ‘problem’ and lead to a bad association with carbs when in fact they are not, directly at least, the primary driver of body fat gain.
Low carb dieting strategies are effective as a short-term approach to weight loss often without the need to track calories. Low carb diets place a focus on protein which helps with hunger control and dietary adherence and simplifies the dietary approach, removing foods a person may overeat on, which can be helpful for some people.
However, there is nothing magical about low carb dieting approaches; they do not cause more weight loss than other strategies (except lots of water weight is lost in the initial stages) when protein and overall energy intake is matched. There may also be some health concerns if proper attention is not made to ensuring all essential nutrients are met. It is therefore important to make sure you understand these potential issues and employ the appropriate strategies if choosing to undertake a low carb diet.