Sourdough Bread: What the Science Really Says About Its Health Benefits
I started writing this post summarizing all the healthy claims I’ve heard about sourdough bread, but I wanted to include citations from credible sources to support those claims. However, when I started looking at sources to cite in my post, I was surprised that the scientific findings were not as compelling as I was hoping. So, I changed course and decided to make a post that takes a balanced look at the science behind sourdough, and why I believe that homemade, 50/50 whole wheat sourdough can be a nourishing addition to a healthy diet.
🌿 What the Evidence Suggests
Digestibility and gluten
Health claim: The fermentation process in sourdough bread breaks down complex carbohydrates and gluten making it easier to digest. This can be beneficial for people with gluten sensitivities or digestive issues. This may make sourdough bread easier to digest.
What the science says: Some studies do show that the fermentation process involved in making sourdough can partially break down gluten and phytic acid (an anti-nutrient that blocks mineral absorption). Research is limited and there are conflicting studies. Sourdough is not gluten free. It is not safe for people with celiac disease, but it may be easier to tolerate for people with other digestion issues.
Blood sugar response
Health claim: Sourdough bread, especially when made with whole wheat flour, has a lower glycemic response than conventional yeast breads made with white flour. Additionally, the fiber from the whole wheat likely amplifies these benefits.
What the science says: While this is mainly true, it should be noted that the reduction in glycemic response varies widely depending on flour type used, fermentation time, and individual metabolism. Some studies do show modest improvements in blood sugar response compared to other types of bread, while others find little difference. Additionally, sourdough bread is not a low glycemic food and there are other lower glycemic options (Cleveland Clinic).
Gut Health and Probiotics
Health claim: Sourdough bread is good for the gut microbiome and offers probiotic benefits.
What the science says: Sourdough bread itself is not a probiotic food because the live cultures do not survive the baking process. However, it does offer prebiotic fibbers (from whole grains) that can help feed beneficial gut bacteria.
Nutrient Profile and Bioavailability
Health claim: The fermentation process makes nutrients in sourdough bread more bioavailable and more easily absorbed by the body.
What the science says: This claim is mostly supported by the literature. Sourdough has reduced amounts of anti nutritive or inflammatory compounds (Frontiers in Nutrition) compared to other types of bread. Further, the fermentation process improves the bioavailability of minerals, such as zinc and iron, meaning that your body absorbs more of these minerals (Science Direct). Additionally, when making sourdough bread with whole wheat flour, the whole wheat flour provides protein and essential fatty acids, as well as vitamins and minerals such as vitamin-E, B vitamins, iron, magnesium and antioxidants compared to using white flour alone (Springer Link); however, baking the bread does diminish its vitamin content (Science Direct).
🌿 Why Homemade, 50/50 Whole Wheat Sourdough Is a Good Addition to a Balanced Diet
Even though the science wasn’t overly convincing about the benefits of homemade sourdough bread, there are plenty of reasons to include this as a staple in your diet:
Simple ingredients: just flour, water, salt, and starter - no preservatives, added sugar, or fat from any source.
Quality: You control the quality of the ingredients you put into it, so you can choose organic, high quality flour.
Convenience: With a little bit of time and planning, you can have fresh bread whenever you want.
Mindful eating: Sourdough has a rich, complex flavor that encourages slower, more mindful eating. And thanks to the fiber and protein from whole wheat, it keeps you feeling full and satisfied longer.
Helpful part of balanced diet: Sourdough can also help with reaching dietary goals since it has no fat, no added sugar, and contains a modest amount of fiber and protein. Even by itself, it can be a go-to snack to hold you over until the next meal.
It is a fun hobby: Cultivating your starter and baking fresh bred is a fun, wholesome hobby that you and your family can enjoy!