If you keep up with the latest health news (or the Kardashians), you might have heard of the trendy low-carbohydrate ketogenic diet being raved about by celebrities like Kim Kardashian.
Known as the keto diet for short, the diet consists of foods that are low in carbohydrates (5-10%), moderate in protein (30-35%) and high in fat (55-60%). Specifically, in a 2000 kcal per day diet, only 20 to 50 grams of carbohydrates are allowed per day.
After three to four days with low carbohydrate intake (less than 50 grams per day), the body’s carbohydrate stores are depleted and fat becomes the primary fuel for energy. This results in ketogenesis where there is an increased production of ketone bodies. Insulin secretion is also lowered, which reduces fat and glucose storage. This metabolic state is known as “nutritional ketosis”.
The keto diet appears to help in weight loss, especially short-term and this could be due to the fact that the diet is restrictive by removing entire food groups and reduced caloric intake. “People may lose weight with the ketogenic diet, but it is likely due to negative energy balance where their energy intake is lower than their energy output,” stated Ms Nur Azlina, an Active Health Expert. This diet also has a diuretic effect, with some of the early weight loss being due to the loss of water. A balanced eating approach comprising whole grains, lean meats, fruits and vegetables can help achieve weight loss in a more sustained manner.
There are many common misconceptions surrounding the keto diet that could prevent it from being effective or even pose nasty side effects and health risks. Here are some misconceptions surrounding the keto diet.
Being a very low carbohydrate diet, the extreme restriction of carbohydrate-rich foods is key but is it all that great for your body? Not only does the keto diet eliminate sugars and refined carbohydrates, it also limits the intake of whole grains, fruits, pulses and starchy vegetables. These foods are very beneficial for your diet as they are good sources of vitamins, minerals, fibres and phytochemicals. A high dietary intake of phytochemicals with vegetables, fruits, legumes and whole grains is associated with a reduced risk of cardiovascular and other diseases.
Individuals who follow the keto diet are recommended to consume a substantial amount of non-starchy vegetables. Whilst they contain high quantity of insoluble fibre, they are low in soluble and fermentable fibre. These fermentable fibre function as food sources for beneficial microorganisms that help to improve gut health. The beneficial effect of soluble fibre lowering cholesterol levels are also reduced when these food sources are limited.
The keto diet could be a quick way to lose weight but their sustainability over the long run is not proven. As a restrictive diet, many might have difficulties committing to the diet for an extensive period of time and may lead to a yo-yo dieting pattern. The safety and efficacy of this diet has yet to be established and there are also side effects of the keto diet, the most common one being the ’keto flu’. It carries flu-like symptoms such as headaches, weakness, constipation, frequent urination, nausea and vomiting. Other adverse effects may include fatigue, constipation, dehydration, loss of electrolytes such as sodium, potassium and magnesium that are essential for the functions of the kidney and heart. Electrolyte imbalances could worsen the kidney function in those with related health problems.
Just because this diet encourages the consumption of high levels of fat does not mean that it is nutritionally sound. As the keto diet contains high percentage of fat, it is inevitable that the diet will encourage food sources that are high in saturated fats as well as processed foods. The high-fat diet could also drastically raise the levels of low-density lipoproteins (LDL) cholesterol in the long run, which increases the risk of diabetes and heart disease. Some doctors even call it a “cardiologist’s nightmare”. Regardless of diet, you should still be consuming healthy fat over saturated fat found in processed food to reduce risk of heart disease. Some heart-friendly sources of fat are fatty fish, avocados, olive oil, nuts and seeds.
It would be good to consult a dietitian or doctor to find out if the diet is suitable for you, and the safe ways to practise it.
The keto diet requires strict adherence to keeping carbohydrate intake to less than 50 grams of carbohydrates per day, primarily from non-starchy vegetables. After three to four days of lowered carbohydrate intake, the body has no choice but to burn fat for fuel. Most keto diets that are adapted by individuals or prescribed by research may not be truly “ketogenic”. Individuals may think that they are on the keto diet but they may actually be consuming 10g, 50g or even 100g of carbohydrates and this may affect their state of ketosis.
Removing obvious carbohydrate-rich sources may also not be sufficient to force the body into ketosis. There are many sources of hidden carbohydrates that an individual may consume which could remove them from a state of ketosis. Sauces and gravies, battered and processed meats such as chicken nuggets have hidden carbohydrates which may accidentally increase the intake of carbohydrates, preventing this diet from working. Checking the nutritional value of the foods you consume would reveal that the keto diet is not as freeing as you think it is. The levels of ketone production are also very individualised. Therefore, it is necessary to measure ketone levels to determine if your body is in a state of ketosis.
Exercise has immediate and long-term benefits which not only includes maintaining a healthy weight, but also improving health indicators, moods, sleep quality and increased energy levels.
In some studies, there is an increased fat utilisation in athletes on the keto diet as compared to those on a normal diet. The diet is also found to limit performance during high-intensity workouts that require short bursts of energy as fat does not burn as quickly as carbohydrates. However, research shows that some athletes on the diet were able to adapt to burning fat as fuel, leading to significantly higher levels of energy after some time.
Exercise is still recommended to individuals on any specific diet and it would be best to consult with a fitness professional or doctor on the intensity and type of exercise while on the keto diet.
The keto diet might work for some short-term but it is definitely not for all. Everyone has different nutritional needs, thus consulting with a dietitian before embarking on the keto journey is recommended.