Sourdough for a Sweeter Life

Regular bread is often portrayed as an enemy within the diet culture, while sourdough bread is praised for being “Gut-Healthy”.

Usually, when preparing regular bread, only one strain of yeast is used. The one found in the local store. On the flip side, sourdough bread doesn´t incorporate yeast as an external ingredient. Yeasts and lactic acid are produced through the fermentation of microbes in the flour. This is a minor difference, but it goes a long way.

Sourdough is not other but a dough made from flour and water. It´s known as a gut-healthy bread alternative. The fermentation process promises to enhance the overall nutritional value. But what are the additional benefits proclaimed?

Lactic acid bacteria(LAB) and yeasts are the principal microbiota of sourdough. LAB is responsible for acidification (providing flavor and aroma) while yeasts are the leavening agents, meaning they produce gas and help the dough rise. But the number and type of microbes depend on many factors — temperature, fermentation time, cereal, hydration, and even the microbial flora in the environment and the hands of the baker. That being said, any alteration can intervene in the microbiome and, as a result, bring different benefits to the table.

Store-bought sourdough bread typically stands at a higher pH — something to keep in mind. The acidic environment also reduces FODMAPs (short-chain carbohydrates, troublesome to digest for some people). This makes the bread easier to digest, especially for those who suffer from celiac disease, irritable bowel syndrome, or other digestive sensitivity.

Sourdough fermentation maximizes mineral and vitamin bioavailability and bioaccessibility, breaks down anti-nutrient factors, and produces beneficial postbiotics. Anti-nutritional factors like phytate tend to bind to mineral structures, impeding their future absorption. Probiotics, another aspect, cannot survive the high temperatures of baking. What remains are postbiotics — non-living microbial cells and their components — which continue to promote gut health.

In addition, metabolic and antioxidant responses are also favored. In sourdough fermentation, gluten and starch are restructured, improving the overall dough consistency and increasing resistant starch content. This results in a lower glycemic index, indicating a slow glucose absorption, perfect for diabetic patients who have to regulate their sugar intake. SD fermentation also breaks down cereal cell walls through enzymes produced from LAB and yeasts, incrementing antioxidant activity, neutralizing free radicals, and reducing oxidative stress (imbalance between antioxidants and free radicals that leads to cellular damage).

But sourdough benefits don´t stop here. Adding other ingredients to the mixture, such as honey, berries, apple juice, or yogurt, can help boost the microbial diversity, enhance the nutritional value, and introduce a different and delightful taste to the dough.

Further Reading:

*Islam, M. A., & Islam, S. (2024). Sourdough bread quality: Facts and Factors. Foods, 13(13), 2132.*

*D’Amico, V., Gänzle, M., Call, L., Zwirzitz, B., Grausgruber, H., D’Amico, S., & Brouns, F. (2023). Does sourdough bread provide clinically relevant health benefits?. Frontiers in nutrition, 10, 1230043*

*Lau, S. W., Chong, A. Q., Chin, N. L., Talib, R. A., & Basha, R. K. (2021). Sourdough microbiome comparison and benefits. Microorganisms, 9(7), 1355.*