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Thermogenic foods: which are and what are
There are many methods to lose weight and many of them have low scientific evidence that supports them. Do thermogenic foods belong to this category?
To understand what thermogenesis is to understand other concepts, how can you calculate the amount of energy that the organism needs?
What is energy spending?
Energy spending is the amount of energy that the organism needs to carry out the activities of daily life. To know it, three components must be considered: basal metabolic expenditure, food thermogenesis and physical activity.
Basal metabolic rate
Basal metabolism represents the minimum amount of energy necessary to maintain the vital functions of the body when it is at rest. These activities include processes such as breathing, circulation or conservation of body temperature. In children, this value also includes the energy cost of growth.
Although this value represents most of the energy expenditure, there is a variation between individuals depending on their body composition, their sex and their age. For example, they will not have the same basal metabolism two men of the same stature and weight if they have different body composition. Muscle tissue is metabolically more active than adipose tissue, so that one that has a higher percentage of muscle mass will need more energy.
To calculate this parameter, direct methods or direct methods can be used. The indirects are more used since it is easier to apply them. One of the most widespread is Harris Benedict’s equations that estimate the basal metabolic rate from weight, sex and size.
Diet -induced thermogenesis is also known as postpandarial thermogenesis. It is the energy necessary to carry out the processes of digestion, absorption and metabolism after meals.
It can mean between 10% and 15% of energy needs. The range of variation depends on the type of food that is ingested. The expense derived from the digestion of a meal rich in carbohydrates or proteins is greater than that of a fat -rich meal. In addition, this value decreases with age, probably due to the increase in insulin resistance.
Physical activity is the third component of energy expenditure and in many cases the most important. In this value the energy consumed both voluntary and involuntary activities, such as chills.
This is the most modifiable factor of energy expenditure since it depends largely on the lifestyle of each individual. In sedentary individuals, the thermal effect of the activity can be as low as 100 kcal/day; While in very active individuals it can reach 3000 kcal/day.
What are thermogenic foods?
Any substance capable of increasing body temperature is considered thermogenic. Some of the best known thermogenic foods are coffee, green tea, coconut oil, cinnamon or peppers.
The consumption of these foods is associated with an increase in energy expenditure. This happens because its consumption increases body temperature and mammals have to maintain this constant temperature.
Sometimes, thermogenic foods are marketed under the slogan "Fat Food". The reason for this is that the capacity of food to generate heat in our body is associated with the ability to consume more energy. If nutrition could simplify this fact, it would mean that any food capable of increasing body temperature is capable of increasing resting energy expenditure.
What does science say?
When introducing the term Thermogenic Foods in Pubmed, one of the main available evidence search engines, there are results associated with concrete components of food. When it is evidenced that a compound increases basal metabolism, they are usually data obtained or in macrodosis. It is complicated that these results can be extrapolated to humans.
So, although thermogenic theory is clear, scientific evidence does not support the use of thermogenic foods as the only strategy for weight loss. They can be included, as long as they are accompanied by other changes such as the increase in physical exercise.
Therefore, thermogenic foods can be included in food being aware that they do not provide added value to the diet and that in the case of seeking weight loss are not the panacea.