What we thought about metabolism may be all wrong, new study suggests

🌈 Abstract

The article discusses a new international study that challenges the common belief that metabolism inevitably declines during adulthood. The study found that metabolism peaks around age 1 and then gradually declines until around age 20, after which it plateaus until around age 60, when it starts to slowly decline again.

🙋 Q&A

[01] Metabolism Changes Over the Lifespan

1. What are the key findings of the study regarding changes in metabolism over the lifespan?

• Metabolism peaks around age 1, when babies burn calories 50% faster than adults
• Metabolism then gradually declines by about 3% per year until around age 20
• From age 20 to 60, metabolism plateaus with no significant decline
• After age 60, metabolism starts to slowly decline again, by less than 1% annually

2. How did the researchers account for factors that could impact metabolism, such as body size and muscle mass? The researchers adjusted for factors like body size and fat-free muscle mass to isolate the specific impact of age on metabolism.

3. What were some common beliefs about metabolism changes that the study findings contradicted? The study contradicted beliefs that metabolism declines when people hit their 30s, or spikes upward during the teen years or pregnancy.

[02] Implications of the Findings

1. What are the potential implications of the study's findings for infant nutrition and medication dosing?

• The findings highlight the critical importance of infant nutrition meeting the increasing energy demands of growing babies.
• The findings could also have implications for how much medicine people need at various ages, as they may be metabolizing drugs differently.

2. How do the researchers suggest the findings may impact the study of age-related diseases? The researchers suggest the decline in metabolism after age 60 may be related to the increased incidence of non-communicable diseases and disorders that begin in that same time frame.

3. If changing metabolism is not the main driver of weight gain at certain life stages, what other factors may contribute? Other potential contributing factors to weight gain include changes in food intake, activity levels, living environment, and access to resources, as well as sleep changes - a more complex web of factors rather than just metabolism alone.