Not a terribly good article, but assuming the underlying science is robust, it’s interesting to start to get a look at what causes subjective feelings of tiredness.
Despite this huge burden on our collective well-being, the question of what it means to “have energy” had, until recently, attracted surprisingly little medical research. Into the void stepped the trillion-dollar wellness industry, offering no end of ways to boost our vigour with various supplements, diets and lifestyle hacks.
Now, though, scientists are taking a fresh look at what it means to feel energised – or not – and the research is revealing that how we perceive this state largely hinges on the brain’s ongoing assessment of how much energy is available to our cells. This discovery is changing how we think about our general health, opening up possible new avenues to treat clinical levels of fatigue, and suggesting practical things we can all do to stop feeling like we are running on empty.
The fact that so many otherwise healthy people feel so tired doesn’t seem to make sense. Many of us, at least in the West, have easy access to far more calories than we need. If feeling good were simply a matter of calories in, energy out, we would all be bursting with vim and vigour.
So why aren’t we? The short answer is that the energy we can feel – our “subjective vitality” – isn’t like a simple readout on a tank of fuel. Instead, it is an ongoing body-brain estimate of how much energy is available in the body and how much is already accounted for, and an educated guess of whether we have any to spare for what we need to do next.