Metabolism refers to the metabolic mechanisms that the body employs when transforming food (calories) into energy to both maintain life and support physical activity, whether exercise or non-exercise.
Medically reviewed by Dr K on 13th June 2022.
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Metabolism And What You Should Know About It
When it comes to reducing weight or maintaining your present weight, your metabolism might have an impact on your outcomes. If you’re worried about this, it’s a good idea to grasp what metabolism is. It’s also useful to understand what can affect it and, if yours is slower, how to help it speed up.
Source - Health Magazine
Metabolism refers to the metabolic mechanisms that the body employs when transforming food (calories) into energy to both maintain life and support physical activity, whether exercise or non-exercise. Among these procedures are:
- Digesting food
- Delivery of nutrients to your cells through the blood
- Use of energy by your muscles, nerves, and cells
- Elimination of waste products from your body
Your metabolic rate is the rate at which you burn calories or energy. This figure comprises your basal metabolic rate (BMR), which is the number of calories required to sustain vital activities such as breathing and blood circulation, as well as calories burnt during physical exercise.
Your BMR is the most important component of your metabolic rate, accounting for 60% to 75% of total calories spent daily.
Factors Influencing Metabolism
Age: As we become older, our metabolism slows down. According to research, this is because our body composition changes as we age. We progressively lose fat-free mass, and our metabolism slows because fat burns fewer calories than muscle. Changes in our organs as we age might also cause a decrease in metabolic rate.
Sex: Males have a greater metabolic rate than females. According to research, this might be due to females saving energy and storing fat more effectively than men, however, it also seems that changes in other hormones may play a role.
Body Structure: Even while your body is at rest, lean muscle mass burns more calories than fat. As a result, the more muscle you have, the more calories you burn every day and the higher your metabolism. Inflammation may have an effect on energy expenditure in obese patients.
Body Sizes (Height): Your height may also influence your body’s metabolic rate, however in more complicated ways. Taller people have a higher BMR (since they are bigger), yet some study has indicated that they burn fewer calories during exercise, proportional to their body weight than shorter people.
When your height and waist measurements are taken into account, it helps if you are at risk of having metabolic abnormalities like metabolic syndrome.
Body Temperature: In order to maintain a steady temperature, the body expends up to 40% of its overall energy consumption. As a result, if you are subjected to severe temperatures, your body will have to work more. Working harder increases your metabolic rate.
Obese people have lower core temperatures, which some experts believe may have slowed their metabolism and led to their early weight gain.
Caffeine or Stimulants Intake: If you’ve ever had too much coffee or too many energy drinks, you’ve probably seen your metabolism speed up. This is due to the fact that stimulants, such as coffee, may raise your metabolic rate. However, the hazards may exceed the advantages, so this isn’t the healthiest technique to enhance your metabolism.
Hormones: Your metabolism may rise or decrease if your thyroid hormones are not generated appropriately by your body. When the thyroid produces insufficient hormones (hypothyroidism), the metabolism slows, which may lead to weight gain. In contrast, if the thyroid produces too much (hyperthyroidism), it usually promotes to weight reduction.
Pregnancy: Pregnant women have a quicker metabolism. This is related to both an increase in body mass and physiological changes in the body. If the woman begins with low body weight, her calorie and nutrient intake may need to be adjusted to ensure she obtains adequate calories and nutrients.
Food Consumption: When most individuals start a diet, what is one of the first things they do? They consume fewer calories and eat less food. However, your body needs nutrients from your diet to maintain a healthy metabolism. When food is digested, metabolism rises as well.
Activity Level: Your body burns more calories when you move more throughout the day, whether through exercise or ordinary everyday activities like walking or standing. The movement boosts your metabolism, making it simpler to lose weight and keep it off.
Your overall energy expenditure varies from day to day based on your degree of activity, but your basal metabolic rate remains relatively constant.
How to Determine Your Metabolic Rate
To calculate your current metabolic rate, first, compute your BMR or the number of calories your body requires for basic functioning. Having it evaluated in a lab is the most accurate method to accomplish this. Some health clubs also provide metabolic testing (for a fee).
Another method is to calculate your own approximated BMR. There are online calculators available, however if you want to calculate this figure by hand, use the Harris-Benedict Equation:
- Men: 88.362 + (13.397 x weight in kg) + (4.799 x height in cm) – (5.677 x age in years) = BMR
- Women: 447.593 + (9.247 x weight in kg) + (3.098 x height in cm) – (4.330 x age in years) = BMR
Once you know your BMR, you may calculate your total metabolic rate. This figure is a mix of your BMR and the calories used through processes such as exercise and other everyday activities.
Using a fitness tracker is the simplest approach to calculate the number of calories expended as a result of the activity. If you burn 700 calories per day and your basal metabolic rate is 1200 calories, your total energy intake (metabolic rate) is about 1900 calories.
How to Boost Your Metabolism for Weight Loss
There are certain aspects of your metabolism that you cannot affect. You cannot, for example, modify your age or gender. However, there are several things you may do to increase your metabolism and lose weight. These are some examples:
Exercising causes you to burn more calories. Even a little exercise boosts your metabolism. Workouts that are more difficult and intense burn more calories.
- Increase your everyday activity: You don’t have time to exercise? Move about more throughout the day. Walking, climbing stairs, gardening, and cleaning all need your body to work harder and burn more calories.
- Increase muscle mass: You may increase your body composition in order to burn more calories. Strength training activities help you grow muscle, which allows you to burn more calories throughout the day, even while your body is resting.
- Consume the appropriate quantity of calories: Excessive calorie consumption might result in weight gain. Consuming insufficient calories might cause your metabolism to lag. Make sure you’re getting enough calories to keep your metabolism running smoothly.
Your metabolism will fluctuate somewhat from day to day. It may be simpler to accomplish long-term weight reduction and maintenance if you can learn how to control and maintain a healthy metabolism on a daily basis.
- U.S. National Library of Medicine. Metabolism. Updated Apr 02, 2021.
- Comana F. Resting metabolic rate: How to calculate and improve yours. National Academy of Sports Medicine.
- Geisler C, Braun W, Pourhassan M, et al. Age-dependent changes in resting energy expenditure (REE): Insights from detailed body composition analysis in normal and overweight healthy Caucasians. Nutrients. 2016;8(6):322. doi:10.3390/nu8060322
- Wu B, O’Sullivan A. Sex differences in energy metabolism need to be considered with lifestyle modifications in humans. J Nutr Metab. 2011;2011:391809. doi:10.1155/2011/391809
- Shan B, Wang X, Wu Y, et al. The metabolic ER stress sensor IRE1a suppresses alternative activation of macrophanges and impairs energy expenditure in obesity. Nat Immunol. 2017;18:519-29. doi:10.1038/ni.3709
- Weyand PG, Smith BR, Puyau MR, Butte NF. The mass-specific energy cost of human walking is set by stature. J Exp Biol. 2010;213(Pt 23):3972-3979. doi:10.1242/jeb.048199
- Liu L, Ping Z, Li L, Yang Y, Li C, Zhang M. [Power and the cutoff value of waist-to-height ration predicting metabolism syndrome]. J Hygiene Res. 2012;41(6):992-6.
- Landsberg L. Core temperature: A forgotten variable in energy expenditure and obesity? Obesity Rev. 2012;13(S2):97-104. doi:10.1111/j.1467-789X.2012.01040.x
- Liu A, Arceneaux III K, Chu J, et al. The effect of caffeine and albuterol on body composition and metabolic rate. Obesity. 2015;23(9):1930-5. doi:10.1002/oby.21163
- Kawicka A, Regulska-Ilow B. Metabolic disorders and nutritional status in autoimmune thyroid disease. Postepy Hig Med Dows (Online). 2015;69:80-90. doi:10.5604/17322693.1136383
- Most J, Dervis S, Haman F, Adamo K, Redman L. Energy intake requirements in pregnancy. Nutrients. 2019;11(8):1812. doi:10.3390/nu11081812
- Kullman S, Kleinridders A, Small D, et al. Central nervous pathways of insulin action in the control of metabolism and food intake. The Lancet: Diabetes & Endocrinology. 2020;8(6):524-34. doi:10.1016/S2213-8587(20)30113-3