By Marcela Barillas
Metabolism is the combination of all the chemical processes that allow an organism to sustain life. In the case of humans, this includes converting the energy from food into energy for vital tasks such as breathing, circulating blood, building and repairing cells, digesting food, and eliminating waste. The minimum amount of energy required to carry out these basic processes while an organism is fasting and at rest is known as the basal metabolic rate or BMR.
Total energy expenditure (TEE) is a combination of BMR, plus the energy used for physical activities and the energy used to digest food (known as dietary thermogenesis). In sedentary adults, BMR represents between 50% and 70% of total energy expenditure, dietary thermogenesis between 10% and 15%, and physical activity accounts for the remaining 20% to 30%.
Many factors affect energy expenditure, such as age, sex, body mass, body composition, physical activity, and diseases. The common belief is that as we age, our metabolism slows down, and the rate at which we break down food decreases by 10% each decade after the age of 20. However, a study that included 6,421 people ranging in age from 8 days to 95 years from 29 countries challenged this belief.
This study revealed that metabolism reaches its peak at around one year of age, when babies burn calories about 50 percent faster than adults, and then gradually decreases by about 3 percent per year until around 20 years of age. Then, during adulthood from 20 to 60 years, both total and basal energy expenditure remain stable, regardless of gender.
Researchers demonstrated that metabolism decreases again around the age of 60 by about 1 percent per year. This study suggests that midlife weight gain can no longer be blamed on a slow metabolism. However, the study’s findings do not invalidate our current knowledge about how to achieve and maintain a healthy weight throughout life.
Here are some tips for maintaining an adequate weight:
- Follow a healthy, balanced diet composed mainly of whole foods such as fruits, vegetables, lean proteins, and whole grains.
- Keep an active lifestyle with a goal of at least 150 minutes of physical activity per week, including strength training to increase or maintain lean muscle mass.
- Get enough rest, which for most people means sleeping between seven and eight hours per day.
- Manage stress through meditation or other relaxing activities.
Source: Esto es azúcar