Metabolism literally means all the chemical reactions that take place in body, to keep us alive. These metabolic reactions ultimately decide the number of calories that can burn in a day. This means, higher metabolism implies higher calorie burn and vice versa. According to an extensive study carried out by Professor Herman Pontzer and his team, the greatest predictor of metabolism is fat-free mass. Fat-free mass is made up of muscles and organs- tissues that contribute the most to your daily energy expenditure. They also found that metabolism remains steady during the middle ages i.e. from age 20 to 60 years. Metabolism after 60 years of age, starts declining at an average rate of 7 % every decade.
The process of aging has a significant impact on metabolism because aging affects muscle mass and that has an impact on metabolism. It is known that the muscle mass decreases every decade after the 30 years of age. The loss of muscle mass with age is known as sarcopenia, which can lead to fractures, weakness, fragility and death. Sarcopenia can decrease your metabolism which has an impact on the resting metabolism.
With age the level of activity also decreases which further has an impact on the metabolism. Decreased activity in combination with sarcopenia can reduce the metabolism with age, which implies that it is easier to gain weight and harder to lose weight. Age-related changes in the body makes it very crucial to focus on reducing these changes and hence improve healthspan as well as lifespan. Targeting these age-related changes like slower metabolism, can help us improve longevity. There are various ways to combat these age-related changes in metabolism; healthy eating habits, increasing the fat free mass by regular strength training, healthy sleep is some of the known ways for the same. Knowing your biological age and tracking age-related biomarkers are some of the evolving ways of achieving longevity.