The key difference between fast and slow metabolism is the number of calories burnt during the metabolism. Fast metabolic reactions burn more calories whereas slow metabolic reactions burn fewer calories.
Metabolism refers to the total number of metabolic reactions taking place in an organism. Hence, all the biochemical reactions that are happening in an organism included in the metabolism. There are two types of metabolic reactions namely anabolic reactions and catabolic reactions. Furthermore, based on the amount of calories burnt during metabolic reactions, metabolism has two main categories; fast metabolism and slow metabolism. Fast metabolism refers to the metabolic reactions that burn more number of calories. On the other hand, slow metabolism refers to the metabolic reactions that burn less number of calories. Fast metabolism takes place due to several reasons such as the high thermic effect of food, gender, age and other anthropometric measurements while slow metabolic reactions take place due to the low thermic effect of food.
1. Overview and Key Difference
2. What is Fast Metabolism
3. What is Slow Metabolism
4. Similarities Between Fast and Slow Metabolism
5. Side by Side Comparison – Fast vs Slow Metabolism in Tabular Form
What is Fast Metabolism?
Fast metabolism is the phenomenon in which the metabolic rate is fast, thus burns number of calories rapidly. Hence, fast metabolism lowers the rate of weight gain despite the larger food consumption. Basically, fast metabolism depends on the genetic make-up of an individual. But there are varied factors affecting fast metabolism. They are thermogenicity of foods, age, gender, physical activity levels, muscle mass and diet patterns.
Furthermore, working out and building muscle will also increase the metabolic rate. Thus, when sportsmen and sportswomen consume a high-calorie diet, it does not show a significant weight gain in them. The most interesting thing about the fast metabolism is that the people who have a fast metabolism can eat a lot without gaining weight. But, those people should consume plenty of healthy and well balanced three meals plus snacks during the day.
What is Slow Metabolism?
Slow metabolism is the process in which the metabolic rate is very slow. Thus, the time consumed for metabolizing components is more. In contrast to fast metabolism, slow metabolism does not burn more calories fast. Therefore, even if an individual consumes a lesser food intake, the complementary weight gain is high. Similar to the fast metabolism, slow metabolism also depends on factors such as thermogenicity of food, exercise patterns, age, gender, diet patterns and genetics. Among all the factors affecting slow metabolism, genetics play a major role. Furthermore, foods with low thermogenic index contribute a lot to the slow metabolism in individuals.
When the individuals show high sedentary behaviours, it favours the slow metabolic processes. Thus, fewer calories are burnt. Therefore, in a healthy individual, slow metabolism not favours clinically. Slow metabolic rates can lead to the deposition of compounds such as fat leading to cardiovascular disorders.
What are the Similarities Between Fast and Slow Metabolism?
- Both fast and slow metabolisms involve either anabolic or catabolic reactions.
- Also, both involve biochemical reactions catalyzed by various enzymes.
- Moreover, genetics plays an important role in both types of metabolism.
- Age, gender, levels of physical activity, diet patterns, sedentary behaviour and thermogenicity of foods affect both the types of metabolism.
What is the Difference Between Fast and Slow Metabolism?
If a person has a fast metabolism, he or she can eat a lot without gaining the weight. In contrast, if a person has a slow metabolism, he or she must be careful with the food intake. This is due to the fact that, fast metabolism burns more calories while slow metabolism burns fewer calories. Hence, the deposition of fat is high in slow metabolic person than the fast metabolic person. Therefore, this is the key difference between fast and slow metabolism.
The below infographic on difference between fast and slow metabolism shows a more detailed comparison of both metabolisms.
Summary – Fast vs Slow Metabolism
The classification of fast and slow metabolism depends on the calories burnout during the metabolism. During the fast metabolism, the calorie burning rate is high. In contrast, during the slow metabolism, the calorie burning rate is low. Therefore, a fast metabolic individual will not have an increased weight gain in comparison to a slow metabolic person. In both metabolisms, genetics plays a major role in determining the rate. In addition, factors such as age, gender, thermogenicity, physical activity and diet also determine the pattern of metabolism of an individual. This is the difference between fast and slow metabolism.
1.Ballantyne, Craig. “Why Do Some People Have a Fast Metabolism.” Early To Rise, Early to Rise, 12 Oct. 2017. Available here
2.Samuels, Mike. “The Advantages of a Slow Metabolism.” Healthy Eating | SF Gate, 11 June 2018. Available here