THE PROOF THAT BREAD ALONE IS NOT ENOUGH
In the Video below you will see Jamie sharing her finding form her PhD. Jamie-Lee Cronje works in Clinical Psychology at Royal Holloway, University of London, and her thinking is rooted in nutritional psychiatry. Professor David Veale has long been a supporter of the work we do here, and Jamie-Lee’s curiosity, combined with her knowledge of psychology, lifestyle medicine, and the science of baking, brought her to The School. Her passion for mental health grew, like many within the system, out of frustration with conventional approaches to treatment — particularly the dependence on pharmacological solutions that so often overlook the human context of healing. Many therapists are now beginning to recognise that we need a multifaceted approach to mental health, and so when the opportunity presented itself, Jamie-Lee used her PhD to look closely at bread.
A month on the highest fibre bread we make then a month on an industrial sliced White – for 4 months
Jamie’s research, conducted in collaboration with The Sourdough School, as Vanessa baked the bread each week and anonymously delivered them to the Greenview Doctors surgery in Northampton where participants would pick them up late in the day. The clinical study Jamie designed isolated the effects of eating a high-fibre, long-fermented sourdough bread against those of a standard ultra-processed white loaf.
A challenge
Ethical restrictions meant participants could not follow the full Baking as Lifestyle Medicine (BALM) Protocol. They were asked only to eat the bread — nothing else about their routine, diet, or lifestyle changed. The results revealed something vital. While daily ratings showed small improvements in mood and anxiety, these gains did not translate into significant changes on standardised clinical scales.
Jamie-Lee’s analysis identified why:
- The bread alone, no matter how nutritionally advanced, could not compensate for the absence of behavioural and social engagement.
- Four weeks to expect change from gut microbial composition was too short to make significant change to the gut microbiome, but without the wider context of connection, movement, and shared purpose, the intervention remained partial. The study did not look at gut changes, but the mental health outcomes confirmed that behavioural change is key to supporting mental health. What was fascinating though was that the participants reported feeling better day to day.
For me, the conclusion was clear — bread alone is not enough. Real change, and the positive results seen in my own research and case studies, requires the whole system of practice that the BALM Protocol represents: baking, sharing, connecting, community, feeling empowered, and time.
Jamie-Lee’s meticulous, reflective research provides a marvellous and essential piece of evidence for why lifestyle medicine must be lived, and mimic the prescription of bread as a pharmaceutical pill type therapy. This confirmed what I intuitively know – that the reasons I use tasks that connect the baker to the system, soil, farmer, miller and wider relationships in the Diploma and in the BALM approach that this is about building a foundation for lifestyle medicine and behavioural change rather than just saying eat bread made like this.
What can we learn from this
So while the study itself focused narrowly on bread alone, its outcome acts as a control condition for your wider body of work. To me it proved by omission what my own own case studies and longitudinal BALM research demonstrate in practice — that the positive mental health changes depend on the integration of behaviour, connection, and meaning alongside the nutritional intervention.
To put it in research language:
- The sourdough intervention alone improved subjective well-being (participants felt better), but it did not significantly change standardised mental health scores.
- The absence of behavioural activation (baking, sharing, and engaging) and social connection meant the intervention lacked the psychosocial mechanisms known to drive sustained mood improvement.
- Therefore, by contrast, the full BALM Protocol — which intentionally includes those mechanisms — is the active model that produces significant clinical results.
So this study acts as a proof point that the BALM Protocol works because it’s multidimensional and the most important word for me is empowerment .. the BALM protocol empowers. Yes the fermentation, fibre, and nutrients matter, and we saw significant change in the gut in my own studies — but the transformation comes from the BOTH the nourishment as well as the act of baking, the connection to others, and the sense of agency and belonging that accompany it.
A huge congratulations and a massive that you to Jamie on being Dr Jamie-Lee Cronje. She put an extraordinary amount of work into this project and overcame some very challenging ethical constraints. Thank you for this amazing work it has really helped me realise just how important the whole holistic approach is. I also want to thank our in-house GP Dr Ed Copley and Tiffany Crawford for their incredible support in finding participants.
