Your gut: a neurotransmitter powerhouse

The gut is home to trillions of microbes, collectively known as the microbiome. These microbes influence the production of key brain chemicals like serotonin, dopamine, and GABA – neurotransmitters that affect your focus, mood and sense of calm.

A healthy gut also produces short-chain fatty acids (SCFAs) through the fermentation of fibre. SCFAs, particularly butyrate, have been shown to reduce systemic inflammation and improve memory and cognitive performance. This is all backed up by a 2023 study published in The National Library of Medicine.

Your liver: the body’s filtration system

The liver processes everything that comes through the digestive system: nutrients, hormones, medications, alcohol and microbial by-products. It helps regulate estrogen levels, clears excess cortisol and manages inflammatory signals that can otherwise affect brain function.

Because the gut and liver are connected via the portal vein, any imbalance or dysfunction in the gut (like bloating, food sensitivities, or constipation) increases the liver’s workload. Over time, this can result in a buildup of internal stress that manifests as fatigue, low mood or mental fog.

According to a study in the Journal of Hepatology (2021), elevated levels of endotoxins and inflammatory markers from gut-derived sources have been linked to neuro-inflammation and cognitive impairment.

Your brain: the responder

The brain receives constant input from this internal network. When the gut–liver axis is functioning well, the brain benefits from a steady supply of nutrients, neurotransmitters, and anti-inflammatory signals. But when the system is under strain – due to stress, poor diet or toxin overload – brain fog can quickly follow.

Put simply: when your body is inflamed, your brain feels it.

This is why persistent brain fog during menopause isn’t always “just hormones.” It can be a sign that your internal detox and communication systems need support.

Hydration

Water plays a key role in flushing metabolic waste, supporting lymph flow and maintaining optimal brain function. Dehydration has been shown to impair short-term memory, attention and mood – even in mild cases.

A study published in The National Library of Medicine named ‘The Hydration Equation’ found that cognitive performance declined in women with just mild dehydration (1–2% body mass loss), especially in tasks requiring attention and executive function.

Aim for 1.5–2L of water per day, more if you’re active or in a warm climate.

Liver-supportive foods

The liver is one of the primary organs involved in breaking down hormones, medications, alcohol, and dietary toxins. Certain foods can support this function by enhancing enzyme activity and reducing oxidative stress.

According to the journal World Journal of Gastroenterology (2015), cruciferous vegetables like broccoli and cauliflower stimulate phase II liver detoxification enzymes and help modulate oestrogen metabolism.

Leafy greens, bitter herbs (like dandelion and rocket), garlic and turmeric also support liver enzymes and bile production – key for hormone clearance and fat digestion.

Gut-supportive foods

As we’ve established, your gut and liver work closely together. The gut microbiota influences neurotransmitter production, inflammation and how efficiently toxins are processed. When the gut is sluggish or imbalanced, your cognitive clarity often suffers too.

Research in Frontiers in Neuroscience (2018) describes the gut-brain-liver axis as central to mental health, noting that dysbiosis can increase brain fog, anxiety, and poor mood via inflammatory and metabolic signalling pathways.

Include plenty of fibre (vegetables, oats, flaxseed), fermented foods (sauerkraut, kefir, miso), and consider a high-quality probiotic if appropriate.

Light sweating

Movement supports circulation, lymph drainage, and gentle sweating – all of which help the body eliminate toxins more efficiently.

A study in the Journal of Environmental and Public Health (2011) found that sweating can facilitate the excretion of environmental toxins such as BPA, phthalates and heavy metals.

You don’t need to hit the gym hard; walking, stretching or even a warm sauna can be enough to support these processes in a sustainable way.

Breathing & mindfulness

Stress increases cortisol, a hormone that – when chronically elevated – can impair detoxification, digestion and cognitive function. Intentional breathing and mindfulness can help calm the nervous system and reduce that load.

According to Psychoneuroendocrinology (2017), regular deep breathing practices activate the parasympathetic nervous system, lowering cortisol levels and improving executive brain function.

Just five minutes of slow, conscious breathing per day can help your body shift out of fight-or-flight and into repair mode.

Think of these habits as removing background noise from the body. With fewer stressors and more internal balance, your brain can do what it does best – process, focus and think clearly.