SOURDOUGH AND HEALTH
Let's have a look at the health properties of sourdough bread.
First of all, the grains we use to make our daily bread; wheat, rye and barley for example, are an important source of minerals like potassium, phosphor, iron, magnesium and zinc. However those grains also contain phytic acid. When making a dough with those grains, the phytic acid binds with those minerals, which prevents the majority of them from being absorbed into our body through the gut. This is especially true for breads made with commercial yeast which have a short proofing time.
In sourdough bread this is different. The wild yeast cells, enzymes and lactobacilli break down the phytic acid during the long proofing and fermentation time needed to produce sourdough bread. The minerals are being released which means they can now be absorbed by our body.
Other than that sourdough has a lower glycemic index than normal bread. This means that the consumption of it does not give a spike in the blood sugar level. It releases its energy in a normal constant flow.
Lastly: Sourdough is probiotic. Even after baking, lactobacilli and enzymes continue to develop in the bread. As the bread ages, the flavour changes from sweet-tangy to more tangy and it contributes to more biodiversity in our intestines. The crust and chewy crumb of sourdough mean we need to chew it more, which releases more saliva, which in turn helps with a better digestion overall of the bread.