30/03/2026
In your younger years, your brain was very happy running on glucose.
But in perimenopause, that starts to change.
Your brain becomes more reliant on ketones
which are made when you burn fat for fuel, not just glucose.
Here’s where it gets interesting…
Most women have lost the ability to switch between burning glucose and burning fat.
Years of:
• eating little and often
• snacking throughout the day
• constant access to food
means the body doesn’t need to tap into fat stores.
So it downregulates that ability.
Then perimenopause hits
and your brain starts asking for ketones…
…but your body isn’t very good at making them.
And that can feel like:
• brain fog
• poor memory
• lack of focus
• energy dips
This doesn’t mean you need to go keto.
But it does mean your body needs to become more metabolically flexible again.
That’s something I work with clients
because when your brain has the fuel it needs, your brain feels sharper, less fatigued and you remember why you walked into the room.
Send me a message if this resonates, book a free chat if you want to see how I could support you. See the link in my bio and message me directly.