Burning 1kg of body fat takes 13% less effort than you think! You are doing well, you are following a nice training schedule, a diet plan and using supplements like PhenQ to burn that excess layer of fat. But how long does it take to burn 1kg of body fat?
Based on the fact that 1 gram of fat provides about 9 kcal, most people will tell you to burn about 9000 kcal. However, this is incorrect, because there are considerably fewer, which many athletes and sometimes even nutritionists do not know!
The question remains how big the energy shortage must be, to burn the equivalent of energy stored in 1 kg of body fat. This is not 9000 kcal, but about 7800!
How can you explain this?
The explanation for this lies in the physiological fact that body fat stored in humans does not consist of 100% fat, but approximately 87% fat, the rest being fluid (1,2). This means that 1 kg of stored body fat consists of approximately 870 grams of fat. This kg of fat therefore provides approximately 870 grams * 9 kcal is 7800 kcal (or: 9000 kcal * 87%).
How long will it take before I can lose 1 kg of body fat?
A rule of thumb within Nutrition and Dietetics is that a daily energy shortage of about 20% on the recommended daily amount is a responsible (healthy) way to lose weight. So for both a man and a woman, between 400 and 500 kcal (20% of 2000 and 2500, respectively) is justified. A simple calculation therefore brings us to the answer that burning 1 kg of body fat takes about 15 days * (7800/500 = 15).
How much body fat can I lose in 60 days?
An eight-week (+/- 60-day) diet is a much used term for a responsible diet . How much body fat can you (theoretically *) lose if you handle an energy shortage of 500 kcal per day during those 8 weeks. Based on the above calculation, you can lose about 4 kg of body fat in 8 weeks *.
What does all this mean?
We now know that 1 kg of body fat does not contain 9000 kcal but 7800 kcal, which is 1200 kcal less than we initially thought. If we express this 1200 kcal as a percentage of 9000 kcal, this corresponds to 13%! This is more than logical since 1 kg of body fat consists of only 87% fat and therefore contains 13% less stored energy.
