Sourdough bread may seem like just another trendy bakery item, but it’s actually one of the oldest forms of leavened bread in the world. Long before commercial yeast was available, people relied on natural fermentation using wild yeast and beneficial bacteria to make bread rise—this traditional method is what gives sourdough its signature tang and unique texture.

Unlike many modern breads, sourdough is made without added yeast, relying instead on fermentation to create a more flavorful, digestible, and nutrient-friendly loaf. Let’s explore the top reasons sourdough is a smart choice and whether it’s right for your diet.

1. Easier to Digest Than Regular Bread

The natural fermentation process used in making sourdough helps break down gluten—a protein found in wheat, rye, and barley that many people find difficult to digest. Sourdough also contains lower levels of compounds that often trigger digestive discomfort, such as FODMAPs, phytates, and tannins.

These properties may explain why many people with mild sensitivities to gluten or bloating experience less discomfort when eating sourdough. A 2023 review of 25 studies found that individuals switching from commercial yeast bread to sourdough reported better digestive comfort and fewer gastrointestinal issues.

2. Helps Balance Blood Sugar Levels

Thanks to the acids produced during fermentation—mainly lactic and acetic acid—sourdough slows the digestion of carbohydrates, which leads to a more gradual release of glucose into the bloodstream. This makes sourdough a better choice for people who want to avoid blood sugar spikes.

On the glycemic index (GI), which measures how quickly foods raise blood sugar, sourdough scores significantly lower than white bread. For example, a 30-gram serving of white wheat bread has a GI of 71, while the same amount of sourdough has a GI of 54. That difference could help stabilize energy and reduce insulin spikes.

3. Increases Nutrient Absorption

Whole grain and wheat breads often contain anti-nutritional compounds like phytic acid, tannins, and enzyme inhibitors, which can interfere with the absorption of key minerals. Phytates, in particular, can bind to minerals like iron, calcium, and magnesium, preventing them from being absorbed properly.

Fermentation in sourdough production breaks down these anti-nutrients. Some studies show that sourdough can reduce phytic acid content by over 96%, dramatically improving mineral bioavailability. This means your body can absorb more nutrients from sourdough than from many other breads.

Nutritional Profile of Sourdough Bread

Here’s a look at the nutrition content of one medium slice (59 grams) of sourdough bread made with enriched white flour:

  • Calories: 188

  • Carbohydrates: 36.5 g

  • Fiber: 1.8 g

  • Protein: 7.67 g

  • Fat: 1.26 g

  • Iron: 2.28 mg (13% DV)

  • Copper: 0.088 mg (10% DV)

  • Folate: 82.6 mcg (21% DV)

  • Thiamine: 0.252 mg (21% DV)

  • Niacin: 3.17 mg (20% DV)

  • Riboflavin: 0.218 mg (17% DV)

  • Manganese: 0.33 mg (14% DV)

  • Selenium: 17.5 mcg (32% DV)

  • Zinc: 0.619 mg (6% DV)

These values can vary depending on the type of flour used and how the bread is made, but overall, sourdough is a good source of B vitamins, iron, and other key minerals.

Who Should Avoid Sourdough Bread?

Even though sourdough contains less gluten than regular wheat bread, it is not gluten-free. That means it’s not safe for people with celiac disease or those with a medically diagnosed gluten intolerance.

For those avoiding gluten, there are gluten-free sourdough options made with flours like teff, buckwheat, or sorghum. However, these versions often have a different texture because they lack gluten’s chewy elasticity.

A Quick Recap

Sourdough is more than just a delicious bread—it’s a smart nutritional choice. Its slow fermentation process makes it easier to digest, gentler on blood sugar levels, and better for nutrient absorption compared to conventional breads.

It’s rich in B vitamins, minerals like selenium and iron, and offers functional health benefits for digestion and energy regulation. However, individuals with celiac disease or gluten sensitivity should stick to gluten-free versions.

In moderation and as part of a balanced diet, sourdough can be a flavorful and nourishing addition to your meals.