The more you eat foods like vegetables, fruits and nuts, the faster you lose weight. Those who claim that negative calorie foods are effective support the reason that these foods contain a lot of fiber. Fiber will not provide energy for our body, but the body will use some energy to break it down. ...
It sounds reasonable at first glance, but is it really true?
Image source:/biaoqing/detail/id/572898.html.
You can't just talk without practice, you have to come up with experimental results.
There have been many related rumors on the Internet, most of which are theoretically analyzed. Dialectical materialism holds that practice is the only criterion for testing truth. Researchers from the University of Alabama at Tuscaloosa have done just that. They are not going to talk nonsense, but do experiments to refute rumors.
How to do the experiment?
The experimental method adopted by scientists is to measure the metabolic energy of a certain food by the total harvest method.
Metabolites produced in the process of animal life activities, except body heat, gas, trace secretions and epidermal shedding, will be excreted through feces and urine. Therefore, the body heat produced by animals can be measured under closed conditions, and the heat produced by food can be roughly calculated by collecting urine and feces. The heat finally digested is called metabolic energy.
Calculation formula of metabolic energy (source: experimental course of animal nutrition)
Celery is the most famous rumored negative calorie food. Because in most people's impression, celery tastes rough, so I think celery is rich in fiber and can burn calories. ...
Negative calorie food rumored on the Internet: celery (Source: screenshot of a search website)
The experiment of squirrel lizard shows that celery is not a negative calorie food.
Well, since everyone thinks so, the researchers will satisfy everyone and choose celery as the experimental material, and the experimental object is nine squirrel lizards.
Squirrel lizard (source: Wikipedia)
The reason why researchers choose this seemingly strange reptile is that they are omnivores by nature, have a digestive system similar to that of omnivorous mammals, and are gentle and willing to eat celery, so it is easy to conduct research in the laboratory.
Since we are doing digestion experiments, we should do pretreatment first. First, these lizards were kept in cages and fasted for 10 days to ensure that they would not produce feces related to other foods. Of course, this is not enough. The researchers also gave them an enema, which eliminated any interference that residual feces or urine might cause.
After these pretreatments, the researchers took the squirrel lizard to the metabolic cage for experiments. The metabolic cage is small enough to hold a squirrel lizard, which is mainly used to collect urine and feces naturally discharged by experimental animals, so as to calculate its overall metabolism. Urine and feces will be collected separately, so the heat of urine and feces can be calculated separately, which can reduce the calculation error.
The desert groundhog is in the metabolic cage (source: www.eurekalert.org).
The enclosed space controls the air in and out, so that researchers can accurately measure how much energy squirrel lizards consume to eat this celery meal in a specific time.
Squirrel lizards began to eat after entering the metabolic cage, and each lizard could eat 7.83 0.23 kilojoules of celery. For the next three days, the researchers began to collect their urine and feces every day, and the feces samples were dried and weighed.
Next, put these collected samples into a bomb calorimeter to accurately calculate the heat of feces and urine produced by these lizards. Finally, when they finish eating, give them an enema to ensure that there is no celery left in the lizard.
After collecting the experimental data, the researchers began to calculate whether this celery meal would produce negative calories (the following is the average data for each lizard):
(Source: Reference 1)
As can be seen from the data table, 2.29 kJ is the heat of feces, 1.06 kJ is the heat of urine, 2.53 kJ is the heat generated by digestion, and 1.89 kJ is the net energy intake. The final calculated metabolic energy of celery is 23.4%.
In a word, this result shows that celery is not a negative calorie food. The celery with 7.83 kilojoules was finally absorbed by the squirrel lizard with 1.89 kilojoules. Although this is not an experiment for humans, this calculation result does not apply to humans, but the researchers said: "If humans eat these celery, they will only consume higher calories."
Can you lose weight by eating enough celery? Yes, but not realistic.
Of course, if you plan to keep eating these celery, you can also lose weight.
Although every bite of celery eaten by these squirrel lizards will bring calories, the total calories they consume in these three days are negative. This is because in three days, the basic metabolism of lizards (the minimum energy metabolism necessary to maintain basic life activities such as heartbeat and breathing, called basic metabolism (BM)) will eventually exceed the total calorie intake of celery, and at least 6 kilojoules of calories will be lost.
If you only eat celery for three days, the squirrel lizard will lose 6 kilojoules, while the female human will lose 4,023 kilojoules (image source: reference 1).
In other words, if you plan to eat only a small dish of celery every day, you will probably starve to death, but as long as you eat enough, the total calorie intake can still meet the needs of the human body for one day, provided that you can eat so much celery. Because of this, squirrel lizards usually eat not only celery, but also some high-calorie foods, such as kale, mustard, carrots, pumpkins and crickets rich in protein.
At this point, we can say that the final conclusion of this experiment is that celery is not a negative calorie food.
Here is another episode: the son of the scientist who did this experiment once proposed to do a negative calorie human experiment and wanted to be an experimental volunteer. But when he heard that he would collect his feces to dry, he resolutely refused.
References:
1, Badmel, K.M., Alexander, A.E., & ampSecor, S. M. (20 19). Negative calorie food: an empirical test of fact or fiction. doi: 10. 1 10 1/586958
2. Yuan Ying, experimental course of animal nutrition
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