Sourdough & Diabetes: Our journey into gut health and blood glucose management
It all started on a quiet Sunday morning. As a couple navigating the challenges of Type 1 diabetes (my partner’s reality, not mine), we’ve always been mindful of the impact food has on blood glucose levels. Bread, as you might guess, isn’t always the easiest companion for managing diabetes, but there’s something about sourdough that intrigued us. We’d heard whispers of its health benefits—particularly for the gut and, perhaps most importantly, its lower glycaemic index (GI). Could sourdough actually work for us?
Why sourdough?
Sourdough isn’t just any bread. The fermentation process it undergoes makes it unique in the world of baking. During fermentation, wild yeasts and lactic acid bacteria break down gluten, phytic acid, and other compounds, which in turn can make it easier to digest. It also affects how the bread is metabolised by the body. This is key for anyone, but particularly for those living with diabetes.
For us, the interest lies in the potential impact of sourdough on blood glucose control. The Glycaemic Index (GI) is a scale used to rank carbohydrates based on how quickly they raise blood sugar levels. Foods with a lower GI are absorbed more slowly, helping to avoid the blood sugar spikes that can be problematic for people with diabetes. Sourdough, due to its fermentation process, typically has a lower GI compared to regular white bread.
Tim Spector, a professor of genetic epidemiology at King’s College London, has also written extensively on gut health and the microbiome. His work has reinforced the growing understanding that the health of our gut influences so many aspects of our overall well-being, including insulin sensitivity. That’s when we thought: maybe this could be a beneficial addition to our diet, especially in a diabetic context.
Finding the right balance
Armed with this knowledge, we decided to give sourdough a go. My first step was diving into Vanessa Kimbell’s The Sourdough School: Sweet Baking (affiliate link) —a beautiful and thoughtful book that, while focused on sweet bakes, introduced us to the delicate balance and art of sourdough.
The next step was ordering The Sourdough School book for bread baking, so we could start exploring savoury recipes. Vanessa Kimbell’s research has long highlighted how sourdough is not just a trendy bake but something fundamentally healthier for gut function. As she explains in her books, the fermentation process in sourdough enhances the bread’s nutritional profile and promotes a healthier microbiome, something that could also aid in better glucose control over time.
Early wins and lessons learned
Our sourdough starter had its ups and downs—one day it would rise beautifully, only to slow down the next. This fluctuating activity can be nerve-wracking, but it’s part of the journey. One thing we’ve already discovered is the importance of temperature. A colder kitchen can slow down the fermentation process, so we’ve started keeping our starter in a warmer spot.
We’re also learning that patience is key. The sourdough process is more than just mixing flour and water. It’s about timing, feeding the starter correctly, and letting the dough develop slowly over hours or even days. This slower process mirrors the way we’re learning to approach food and health—methodically, carefully, and with a bit of experimentation.
The role of gut health in diabetes
As someone who’s been reading up on Tim Spector’s research, I’ve become more and more fascinated by the role our gut plays in overall health. Research has shown that a diverse gut microbiome is linked to better insulin sensitivity, and fermented foods like sourdough can support a healthy balance of gut bacteria.
For people living with diabetes, this goes beyond being an interesting fact—it’s something worth considering as part of a more holistic approach to health. Managing diabetes is about more than just counting carbs or adjusting insulin; it’s about supporting the body in every way possible, including gut health. While research on the connection between gut health and blood sugar is still emerging, sourdough seems to be an intriguing and beneficial option to explore.
What’s next in our sourdough journey?
We’re only just beginning, but there’s a lot more to explore. The balance between managing diabetes and enjoying food is always tricky, but sourdough feels like it could be a valuable addition to our toolkit. We’re excited to see where this journey takes us—whether it’s mastering the perfect sourdough loaf or discovering new recipes that work for both our taste buds and our health.