The Gut-Brain Optimisation Protocol
- Difficulty
- Easy
- Time to result
- ~weeks to results
- Steps
- 7
- Confidence
- —
A nutrition protocol aimed at focus, concentration and mood rather than at digestive symptoms, on the premise that a gut which is not working optimally will affect mental performance even with no specific gut symptoms. The mechanism is the gut-brain axis: gut and brain are chemically connected via neurotransmitters produced in the gut, hormonally via the HPA axis, and physically via the vagus nerve — and the gut is the chattier of the two, constantly throwing messages the brain must process, which is noisy and can present as brain fog. Busy people unintentionally narrow their diet, which starves the bacteria that feed this system. The interventions are dietary variety (30 different plants a week), targeted nutrients (omega-3s, B vitamins, anthocyanins) and using gut bacteria to modulate cortisol set-point and serotonin production.
Origin
Extracted from Deep Dive with Ali Abdaal
How to run it
- 1
Check for the non-digestive signals
Look for brain fog, struggling with focus and concentration, low energy, or picking up lots of bugs, infections and viruses — signs you are unusually susceptible. These warrant looking at gut health even with no obvious gut symptoms.
- 2
Audit the narrowness of your diet, not its volume
Busy people under pressure make their diet small — not in volume, but in the types of food eaten. Check which camp you are in: the meal-preppers eating sweet potato and broccoli five days a week believing they're being super healthy, or the meal-to-meal eaters grabbing similar things from different places with nothing planned.
Watch out Both camps limit the fibre types feeding your bacteria and impact gut health whether or not you feel anything in your gut.
- 3
Eat 30 different plants a week
The most important thing for gut health is 30 different plants a week — variety across fruit and veg, but also nuts and whole grains.
Pro tip Break out of the national fixation on oats and wheat; there are many other grain types the gut really benefits from.
- 4
Cover omega-3s
Omega-3s are important for brain structure and help protect against excess inflammation in the brain, which is linked to anxiety and depression. Either have at least two portions of oily fish a week or take omega-3 supplements.
- 5
Cover B vitamins
B vitamins are essential for brain function — they make serotonin, melatonin, dopamine and GABA, the brain chemicals needed constantly. In controlled circumstances, at the right doses at the right moment for the right people, they have been used in place of SSRIs and work in a very similar way.
- 6
Add anthocyanins
Antioxidants, and particularly the anthocyanins in blueberries, are described as amazing for brain health. They also come in red cabbage and other dark purple vegetables. The proposed mechanism is better blood flow to the brain, producing improved mental performance over a very short period.
- 7
Use bacteria to modulate cortisol and serotonin
Gut bacteria communicate with the hypothalamus, which controls cortisol production, and very early in life set where your HPA axis sits — how much cortisol you release under given circumstances. Use gut bacteria to reduce excess cortisol, harness their powers for more serotonin (better sleep, concentration, focus), and calm the distracting messages travelling up to the brain.
Pro tip Testing your microbiome is not necessary — this can be done in clinic without testing.
Watch out We all need some cortisol; the target is not zero but avoiding the loads of cortisol that come with constant anxiety and stress.
In the wild
The guest cites early rodent work as the foundation of the field. Researchers used a model of an autistic mouse and a model of a non-autistic, sociable mouse. They took a microbiome sample from the autistic mouse and gave it to the sociable mouse — and the sociable mouse started to show autistic traits. Swapping them over, the autistic mouse started to become sociable, purely from having its microbiome changed. The guest is careful to add that autistic spectrum disorder in humans is far more complex and cannot be replicated exactly, but that similar studies have since been replicated in humans elsewhere, and that this is what generally gets learned from rodent studies.
→ Established that the gut microbiome measurably impacts mental performance and how the brain works.
The guest describes data on anthocyanins in children. Children given a blueberry smoothie before an exam perform better in that exam than children who did not have one. When the groups are swapped over and the exam level is held constant, the children who had the blueberry smoothie again outperform those who did not — the effect follows the smoothie, not the group. The proposed mechanism is improved blood flow to the brain, producing better mental performance over a very short window, i.e. a direct impact on brain health in that moment rather than a long-term dietary effect.
→ A same-day, repeatable performance difference attributed to a single dietary intervention.
Common mistakes
Assuming no gut symptoms means no gut problem
A gut that is not working optimally can impact mental health and performance with no specific digestive symptoms — it presents as brain fog and poor concentration, which people rarely trace back to diet.
Jumping straight to an ADHD explanation
Ali notes people commonly conclude 'I struggle to focus, I must have ADHD' as an immediate option. The guest's position is that gut optimisation is worth working through before reaching that point.
Confusing clean eating with varied eating
Eating sweet potato and broccoli every day feels super healthy but limits the fibre types feeding your bacteria just as much as unplanned meal-to-meal eating does.
From the transcript
“there is a very strong line of communication between your gut and your brain which we refer to as the gut brain axis and again…”
“the most important thing for your gut health is that you're eating 30 different plants a week”
“if children are given a blueberry smoothie before an exam they perform better in that exam than the children who haven't had a blueberry smoothie”
From the episode
7 Lessons To Build A Life You Love - Season 5 Wrap
Season 5 Wrap