Does Your Metabolism Slow Down as you Age?

 

The answer used to be yes, but recent research has proved that this is NOT the case!   The current research used a method to measure metabolic rate called doubly labeled water.    This involves giving people water with Deuterium (a form of hydrogen) and Oxygen-18 which is a specific form of Oxygen.

Then using urine samples scientists measure how much of each of these unique forms of Hydrogen and Oxygen are being eliminated.   This allows them to know the rate of carbon dioxide production with extreme precision over a long period of time.

Carbon dioxide production can be used to directly and accurately determine calorie burn and metabolic rate.      Doubly labeled water is the Gold Standard for measuring calorie burn/metabolic rate, and this is the first time it was used to accurately measure metabolic rate in over 6,421 people from 29 countries looking at metabolic rate in people from 8 days old to 95 years old.

Game Changer

The result of the study clearly proved that metabolic rate does NOT slow down because of aging between the age of 20 and 60.     After 60 metabolic rate does gradually slow down, but it is very gradual. 

Another surprising finding was that babies have a much higher metabolic rate (50% higher than adult values) meaning that on a pound for pound basis babies burn a lot more calories than adults.

This high metabolic rate declines slowly from birth to age 20, but after that stays very stable until after age 60.   So it IS true that children and teens have a higher metabolic rate.

Take Home

Although metabolic rate burn does not slow down from aging in and of itself - other factors can result in your metabolic rate slowing down!   Loss of lean mass with aging can and does result in a slower resting metabolic rate.    The loss of muscle from aging, known as sarcopenia, CAN result in a lower metabolic rate.

To make things worse the more muscle you lose the lower your activity levels tend to be and it becomes a viscous cycle:    lower muscle = less activity = less muscle!

This is why it is so critical to include strength training in your fitness program as you age because it can prevent this loss of muscle and help maintain higher activity levels and metabolic rate!

For more information on Sarcopenia and Reduced Metabolic Rate click here:   https://www.mdpi.com/1422-0067/21/2/592/htm