The ‘rise’ of home baking, especially sourdough breads, has taken hold in home kitchens over the last few years. It is a fascinating combination of science and art due to the fermentation process that gives sourdough its unique flavor and texture. However, sourdough is far from being a new development – it is a rustic and time-honored bread-making tradition that is one of the earliest forms of baking.
Beyond its distinct texture and taste, sourdough offers a host of potential health benefits due to its unique cooking processes.
This article explores its positive impact on brain health, making it more than just a delicious choice for your morning toast.
Baking with sourdough involves a characteristic fermentation process using natural yeasts known as Saccharomyces cerevisiae and lactic acid bacteria from the environment. When flour and water are mixed together, forming the ‘starter’, the yeast ferments sugar in the dough, producing carbon dioxide gas which causes the dough to rise and gives the characteristic airy structure.
During fermentation, the lactic acid bacteria produce a number of acids which serve two purposes: these organic acids give sourdough its classically ‘tangy’ taste, and they create an acidic environment which inhibits the growth of harmful bacteria, helping to preserve the bread for a longer shelf life. As the dough is kneaded, gluten proteins in the flour form a network that traps the gases and contributes to the chewy texture.
It is the fermentation process that both reduces the gluten content in sourdough and makes the nutrients within flour more easily digested and absorbed through the gut. A 2011 article published in the Journal of Cereal Science led by a team out of Spain investigated the link between sourdough and the gut-brain axis.
While all whole-grain baked goods and cereals are valuable and rich sources of fiber, vitamins, and micronutrients – the ingredients and baking process can impact the way in which we absorb these minerals. Phytates are a natural compound found in wheat, cereal, and legumes that pass through the digestive tract and bind to micronutrients in flour, making these minerals difficult to absorb through the gut.
Sourdough fermentation creates an acidic environment and lowers the phytate concentration by up to 70%! This process allows for an increased uptake of iron, calcium and zinc – allowing for these nutrients to be utilized by the body as building blocks.
Building on the science behind sourdough’s effects on the gut, a follow-up article in the 2021 edition of Food Microbiology based out of Italy analyzed the gut microbiome of individuals who consumed either sourdough bread, or bread made from baker’s yeast (which is the type that you can buy in the grocery store aisles).
The team found that on average, individuals who were fed the sourdough bread had a microbiome that was richer in short chain fatty acids and amino acids throughout the colon. These results suggest that again, the fermentation process seems to have positive impacts on the composition of the gut microbiome.
Through the gut-brain axis, a balanced microbiome has been linked to improved mood, reduced levels of inflammation, and better overall cognitive function.
While studies are still emerging in this exciting field, research has linked diets rich in fermented foods with decreased stress response, anxiety and overall markers of inflammation. Interestingly, this relationship between the gut and the brain goes in both directions – psychological stress and depression have both been shown to correlate with alterations in the gut microbiome and have been linked with symptoms of abdominal pain, bloating and cramping.
With bread making up about 10% of the typical adult caloric intake, there is a great potential to seek out a more nutrient-dense option that can enhance our physical and emotional health through positive benefits in the gut microbiome. The fermentation process not only imparts a unique flavor and texture – but also offers potential benefits on improved digestion, absorption of nutrients and optimization of the gut-brain axis. So, the next time you savor a slice of freshly baked sourdough, you can do so knowing that it might be nourishing both your taste buds and your brain.
