[Dan Evans]

Okay, I see how higher CO2 levels are making old forests work as carbon sinks but how does that relate to dietary restriction in animals?

[Doctor Stochastic]

The articles seems short on sequitur.

[Rennes Templar]

It appears that the analogy is based late life intervention; trees did better with more CO2, and animals do better with less food, but both results can be obtained late in life.
I am a proponent of CR (calorie reduction) to benefit overall health. I enjoy the benefits of it personally. The body spends a lot of energy on digestion. The less coming in, the less metabolic wear and tear. The key is to see that what food is eaten is balanced.