If you ask most people how they would recommend losing weight in the most basic form, they will usually answer “Eat less, exercise more”. Generally, they are right. The simplest way to lose weight is to create a calorie deficit: that is, burning more calories during the day than you are taking in from your food. However, contrary to what you might think, that deficit should not be too big. Rather than help you lose weight, extremely low calorie diets can often lead to weight loss slowing down. The question is, why?
When you dramatically reduce your calorie intake, your body reacts as if it is in danger. Your metabolism, which is the process by which food is converted to energy, actually slows down. It adjusts to the expectation that it will continue to receive too few calories, and as a result, starts to store fat for future use. Conversely, those with a fast metabolism can often eat far more than others, as their body processes this food into energy at a quicker rate.
While very low calorie diets can have an instant impact on weight loss, it is not sustainable, and even if you continue with a low calorie diet, your body will have adjusted. As a result, the rate at which you lose weight can slow down, or even stop altogether. The problem here is two-fold; not only are you no longer losing weight on a low calorie diet, but the moment you increase your calorie intake your weight will increase disproportionately, as your metabolism is still operating slower than it should be.
Quite aside from not being conducive to consistent weight loss, very low calorie diets are also bad for your general health. The effects can range from feeling lethargic and dizzy to low blood pressure and heart rhythm abnormalities. Understanding calories is an important part of weight loss, but starving your body is certainly not the way to go about it.
The mantra of “eat less, exercise more” needs to be taken sensibly. It does not mean cut your calories in half and start walking ten miles every day. It means having a balanced diet with an appropriate amount of calories received from healthy foods, while exercising a reasonable amount. Those who consistently maintain a moderate calorie deficit and lose weight at a slow but steady pace are statistically proven to be far more likely to maintain their weight loss. Starving yourself might seem like a good idea, but all you are doing is harming your chance for stable weight loss.