The concept of negative calories is fairly new and yet it has been used as a guideline and basis for many diets. The idea behind this is that there are certain foods that burn more calories than they contain. With this trick, the pounds should fall off while eating. But is that true? Are there really negative calories?
It’s too good to be true: Unfortunately, it’s a diet myth. While there are foods that can actually boost your metabolism and burn fat, and others that are very low in calories, there is not a single food in the world that burns more digestive energy than the body supplies. In the following we explain why a minus calorie diet is hardly possible.
Your body burns calories all the time
The body needs energy for every movement and every body process, and food drives the body’s power plant. Food provides the energy necessary for your heart to pump blood, your lungs to breathe air in and out, and all other body systems to function properly, including digestion. It is an ongoing process, i.e. breakfast can provide the energy needed to digest dinner. And the simple secret behind any diet is called: calorie deficit. If you want to lose weight, you have to burn more calories than you consume. But that doesn’t mean you have to focus on counting calories. Nutrition expert Richard Hartmann explains on his blog in detail on why counting calories is nonsense, what types of calories there are and how calories can lead you astray. The negative energy balance is just a small aspect of losing weight.
What foods contain negative calories?
To the Foods that are touted as being calorie-burning, include celery, apples, pineapples, broccoli, asparagus, grapefruit, cucumber, kohlrabi, radishes and other spicy foods. Cold water and ice cubes are also sometimes referred to as negative calories because the body burns extra calories to warm them up in the digestive process.
To understand why it is impossible for certain foods to burn calories when digested, one should also understand what a calorie actually is. By definition, a kilocalorie is a physical unit and represents the amount of energy that is required to warm one liter of water by one degree Celsius. With regard to food, a calorie indicates the energy content of food, i.e. the physiological calorific value that is made available to the body during the utilization of nutrients. Water has zero calories, and foods high in water are very low in calories, but no food has a negative energy value.
The thermogenic effect on digestion
When your body burns calories to digest food it is called this Process thermogenesis. For thermogenesis, an average of 10 to 20 percent of the calories in a food are used to digest it. Proteins have a greater thermogenic effect than carbohydrates or fats. So if an apple has about 52 calories, digesting that apple will require an energy expenditure of about 10 calories. 42 calories are left over and stored in the cells as energy. To get negative calories, the body would have to use more than 100 percent to digest the apple – and that’s impossible.
Losing weight through negative calories is not possible
There are already many websites online listing foods with negative calories, as well as numerous diet programs that promise quick weight loss. These foods are perfect for losing weight, but not because they contain minus calories. Most of the foods on these lists are very low in calories and can therefore be safely eaten while on a diet.
So instead of looking for negative calories, focus on a healthy, balanced diet in conjunction with exercise and try to keep the calorie balance in the negative range more easily. However, you will not lose weight while eating.