
Your brain isn't tired. It's running on the wrong fuel.
By your 40s, your brain's ability to use its primary energy source, glucose, starts to decline. It's not burnout. It's metabolic stress.
In a 2025 PNAS study, researchers showed that midlife marks a critical window: your brain's network stability declines, driven by energy deficits.
But there's a workaround: ketones, the cleanest, most metabolically efficient fuel source for our cells.




