The ketogenic diet is high-fat, low-carb and moderate protein. The theory behind keto and the reason many people use it for fat loss is that by restricting carbohydrates your body will eventually reach a state of ketosis – a metabolic state whereby it burns fat for energy. Ketosis can only occur when carbohydrates are kept at extremely low levels (usually below 30/40g per day).
KETOGENIC DIET: THE PROS
Can help you lose body fat
Research, anecdote, and proponents of the diet have boasted that going keto can help you lose body fat. When you strip away the body's main source of energy (carbohydrates), it's forced to adapt by using body fat for fuel. The Gifu University of Japan found a ketogenic diet does show a marked impact on the amount of body fat that you can burn off and metabolize for energy. In addition, eating higher-fat foods throughout the day can help minimize cravings and increase feelings of satiety, ultimately helping you stay on track and within your recommended daily calorie count.
Benefits a sedentary lifestyle
Sedentary lifestyles are all too common – a factor often dictated by desk jobs and long work hours. Even if you workout for 30 minutes a day, if you aren't moving much the rest of the time, there is ample reason to keep your carbs low since you don’t need the muscle glycogen. Additionally, you can make the carbs you do have work more efficiently for you by timing your intake around your pre- and post-workout schedule.
Reset insulin sensitivity
Insulin sensitivity occurs when the body has a tough time metabolizing glucose and making use of the sugars from carbohydrates. It also reduces the storage of glucose within muscle cells, negatively affecting training, performance, and results. A period of low-carb intake via the ketogenic diet may help boost your sensitivity to insulin, ensuring you can safely reintroduce carbohydrates at a later stage at no cost to physique or performance.
KETOGENIC DIET: THE CONS
Your brain needs sugar
The ability to focus is essential not only for hitting the gym but also for work and your personal life. If you’ve ever tried a very low-carb diet, you're probably familiar with the feeling of sluggishness, especially in the first few weeks. The reason for this is pretty simple: your brain derives energy from blood glucose – which in its most simple sense is a sugar. Carbohydrates are needed for glucose to enter the bloodstream. In the absence of this sugar, your cognitive function could take a hit.
Carbs fuel performance
If you are an athlete or someone who leads a very active lifestyle in general, you might want to avoid ‘going keto’. A 1996 study conducted by Copenhagen University found that a low-carb, high-fat diet resulted in poorer training adaptations when compared to a high-carb approach. The researchers found that both power output and performance in endurance competition were negatively impacted by the ketogenic diet. The International Olympic Committee (IOC)’s published guidelines have since urged athletes to avoid low-carb diets, so you should heed this advice if you want to train and perform at elite levels.
Medical use only
The ketogenic diet is typically recommended in a medical setting, in order to improve the health of those who suffer from conditions such as diabetes, epilepsy and Parkinson’s. In that sense, keto can work. For these people, lowering blood sugars through the removal of carbohydrates, particularly processed ones, may prove necessary in preventing serious health problems. However, you could argue that this has been misinterpreted for use in the fitness world, where carbs help to fuel your workouts with much-needed muscle glycogen.
Calories count most
Weight loss is generally governed by calories in versus calories out. If you are burning off more calories than you consume via food and drink, then you will lose weight – regardless of the ratio of macronutrients (proteins, carbs, and fats) that you adopt. It could feasibly be claimed that, when it comes to weight loss, the ketogenic diet places too much emphasis on fat, and not enough on the overall calorie count.
Research does reinforce the pros of the ketogenic diet – particularly in its ability to target body fat stores for fuel. However, whether this approach is intended to last long-term is up for debate. The loss of water weight is a short-term solution, for one, and you run the risk of tainting your training with prolonged periods of restricted carbs. Glucose provides fuel for the brain, and muscle glycogen for your time at the gym. If you are serious about building muscle mass or achieving peak sports performance then perhaps going keto isn’t for you. The best advice is: consult your physician to determine whether this diet is good for your personal goals, body type, and lifestyle.