Metabolic Adaptation
/Our body has what’s called a “self defense system” which is active during a dieting phase. Metabolic adaptation is your body’s attempt to reduce your total energy expenditure resulting in a decreased metabolic rate. At the start of a diet, it is pretty easy to lose weight because the metabolic rate is still normal. However, as the duration of the dieting phase increases your metabolism slows down to adapt to the decrease in calories. There are many changes in the body that work to slow down energy expenditure including a reduction in Basal Metabolic Rate (calories required for basic body functions), reduction in NEAT (any non exercise activity) throughout the day, and amount of energy expended during exercise.
After a prolonged period of dieting, you may experience that you no longer lose weight while eating low calories. Because of the adaptations mentioned above, what you previously believed to be a calorie deficit may now be your maintenance calories. Calories will need to be adjusted accordingly depending on the goal. You can decide to keep dieting on lower calories or reverse diet (raising metabolic rate by slowly raising calories) to a more sustainable level.