Are you familiar with the phrases: "my stomach is in knots", heard someone say they’ve got "butterflies in their stomach", thought something was "gut-wrenching" or even been told to "trust your gut". Well, these aren’t just idioms, there’s science behind the stress.
This Stress Awareness Month, we’re breaking down the relationship between your body and stress - what research actually says and three evidenced-informed things you and do about it.. Because now, science is catching up to what your body’s been trying to tell you all along.
The gut-brain axis: what it is and why it matters
Your gut and your brain are in constant communication through a bidirectional network known as the ‘gut-brain axis’. What happens in your gut directly influences how you feel mentally, and vice versa.
Chronic psychological stress disrupts the gut microbiome, alters gut motility and increases intestinal permeability. A disrupted microbiome, in turn, amplifies the stress response. It's a cycle and most conventional stress management advice doesn't account for it.
A 2025 cross-sectional study found a strong real-world association between perceived stress levels, dietary quality and gastrointestinal symptoms, reinforcing that gut health is shaped by the interaction of multiple lifestyle variables rather than any single cause (Ahmed et al., 2025). Around two-thirds of participants in that study reported that stress directly influenced their digestion. Most of them also had suboptimal fibre and probiotic food intake - which matters, because what you eat is one of the most powerful levers you have over this system.
PILLAR ONE: Nourish your gut microbiome
The gut microbiome thrives on diversity and fibre. Short-chain fatty acids, produced when gut bacteria ferment dietary fibre, play a key role in stimulating serotonin production in the gut and approximately 90 to 95% of the body's serotonin is produced there, not in the brain (Tang et al., 2025).
This makes fibre intake not just a digestive consideration but a mood and stress regulation one. Polyphenol-rich foods and drinks further support the growth of beneficial gut bacteria and help reduce oxidative stress, one of the key drivers of the gut-brain stress cycle.
Matcha is one of the most concentrated dietary sources of polyphenols available, particularly EGCG (epigallocatechin gallate). A randomised, placebo-controlled trial found that participants who consumed approximately 2g of matcha daily for two weeks maintained significantly better attentional performance under stress, including faster reaction times and improved emotional processing, compared to those who received a placebo (Baba et al., 2021).
Unlike coffee, matcha combines its caffeine with L-theanine, an amino acid that promotes calm alertness without the cortisol spike associated with high-dose caffeine. A systematic review of nine human randomised controlled trials found L-theanine was associated with reductions in subjective stress and anxiety, particularly in individuals exposed to acute stress, alongside reductions in heart rate, blood pressure and along with other bio-markers (Williams et al., 2019).
PILLAR TWO: Move your body, consistently
Exercise is one of the most well-evidenced interventions for stress management, but its relationship with gut health adds another layer. Regular physical activity increases microbial diversity, supports short-chain fatty acid production and reduces systemic inflammation, all of which contribute to a more resilient stress response.
A 2023 review reframes exercise not simply as a tool to reduce stress but as a biological stimulus that reshapes stress responsiveness over time. With repeated exposure to controlled physical activity, baseline cortisol levels decrease, the body recovers from stressors more efficiently, and the nervous system develops greater parasympathetic tone, the rest-and-digest mode that counterbalances the fight-or-flight response (Gerber & Pühse, 2023). The researchers describe this as cross-stressor adaptation: training your body to handle stress, not just recover from it.
The key caveat is dose. The review identifies a U-shaped relationship, too little exercise fails to induce adaptation, while excessive training without adequate recovery can increase cortisol and impair the very stress regulation you're trying to support. Consistent, moderate activity is where the benefits live.
Protein supports muscle repair and recovery, reducing the physiological stress that training places on the body. Creatine supports cognitive function and physical performance, with emerging research linking it to reduced mental fatigue, particularly relevant during high-stress periods.
PILLAR THREE: Protect your sleep
Sleep and stress exist in a feedback loop. Poor sleep elevates cortisol. Elevated cortisol disrupts sleep. Disrupted sleep impairs gut recovery. And an under-recovered gut amplifies the stress response. Round and round it goes.
During sleep, you are in a fasted state. This rest period allows the gut lining to repair, inflammatory markers to reduce and the microbiome to rebalance. Chronic sleep deprivation disrupts this window, with downstream effects on mood, cognitive function and stress reactivity.
Magnesium plays a central role here. A 2025 review identified magnesium as a multi-pathway regulator of sleep physiology, acting through its modulation of NMDA receptor activity, its support of GABAergic inhibitory signalling and its dampening effect on the HPA axis, the system governing cortisol release (He et al., 2025). Low magnesium status has been consistently linked with shorter sleep duration and increased night-time awakenings.
The review also highlights that sleep disturbances are more common in women, where hormonal fluctuations across the menstrual cycle, perimenopause and menopause can alter thermoregulation, circadian rhythm and stress sensitivity. Magnesium's role in relaxation and regulation makes it particularly relevant across these transitions.
The bigger picture
Stress management isn't one thing. It's the accumulation of consistent choices” what you eat, how you move, how you sleep and how those choices interact with the gut-brain connection at the centre of it all.
This Stress Awareness Month, start with the gut.
This article is for educational purposes and does not constitute medical advice. Always consult a qualified healthcare professional or Registered Nutritionist before making changes to your diet or supplementation. If you are experiencing significant stress or anxiety, please seek support from a healthcare professional.
