The ketogenic diet often causes fatigue or tiredness during the initial stages due to several reasons. Firstly, when you restrict carbohydrates, your body needs to adapt to using fat as its primary fuel source, which can take time. This shift in energy metabolism can temporarily lead to decreased energy levels. Secondly, the keto diet can cause a loss of water weight and electrolytes, such as sodium and potassium, which are important for maintaining energy levels. This can result in dehydration and fatigue. Lastly, inadequate calorie intake or micronutrient deficiencies on the keto diet may also contribute to feeling tired. To combat fatigue on keto, it's essential to stay well-hydrated, replenish electrolytes, ensure sufficient calorie consumption, and focus on nutrient-dense foods.