Is Sourdough Bread Healthy? We Asked a Nutritionist

Crunchy on the outside, soft and slightly tangy on the inside, sourdough bread is one of our all-time faves for so many reasons. Have you had sourdough French toast? It’s life-changing. So yes, it’s delicious, but is sourdough bread good for you? We asked nutritionist Stacey Krawczyk, MS, RD, not to break our hearts, and boy, did she deliver.

You know that tangy sourdough taste? That comes from a fermentation process that begins with a sourdough starter, a combination of flour and water. Starters are to sourdough what a packet of yeast is to other breads—you need it to make the bread rise. But you typically can’t just buy a starter at the grocery store; starters are made at least a week before the actual baking of the bread to give live cultures (aka good bacteria) time to develop. The naturally occurring lactobacilli and yeast release lactic acid and carbon dioxide, which adds to the flavor, shape and rise of the bread—they’re also what actually make sourdough bread pretty healthy for you. One of the coolest things about a sourdough starter is that it can last a really, really long time (decades) as long as you keep feeding it. Yep, “feeding” the starter flour keeps the bacteria alive and kickin’. Some families and bakeries pass their starters down for generations! 

Bread hasn’t had the best rap the past few years (thanks, keto diet), but there are actually many nutritional benefits to sourdough.

Sourdough is fermented and, as registered dietician Stacey Krawczyk points out, this is one of the main reasons we can call the bread healthy. When the starter ingredients in the sourdough are mixed and left to sit, lactobacillus (the good bacteria) breaks down and creates lactic acid, which helps your gut better absorb the many nutrients in the bread.

Folate is a B vitamin that’s particularly beneficial for pregnant women because it’s “most associated with preventing neural tube [the pre-central nervous system in a fetus] defects during early pregnancy,” Krawczyk says. Folate is also super important for heart health, and about half the amount we need in a day can come from a thick slice of sourdough. Mmm.

Sourdough is rich in thiamin and niacin, both of which can boost your metabolism. It’s packed with iron for oxygen flow; zinc for your immune system; and magnesium and calcium for bone, muscle and nerve health. Whoa.

Krawczyk says that adding whole wheat flour to your sourdough recipe (either as 100 percent of the flour or as a blend with white bread flour) will add even more of these vital minerals, help control your cholesterol levels and aid in weight management.

To beef up that health factor even more, you can add seeds (like sesame or pumpkin) and grains (like quinoa) to the dough while kneading or as a last-minute sprinkle on top before it goes into the oven for an added protein and fiber one-two punch.

When sourdough is kneaded, it isn’t punched down like many others are, allowing it to retain a lot of air pockets within the dough. This lighter touch creates an airier texture—but this can lull you into a false sense of security. Sourdough is still a carb that you shouldn’t overindulge in (especially if you’re watching your waistline), no matter how light it might taste. “The most important thing is sensible portions and balance,” says Krawczyk, who recommends building a better sandwich with lettuce, sliced fresh tomato, lean roasted chicken breast for protein and healthy fats from avocado.

Making sourdough is a commitment that you have to plan out days in advance, but you got this! To make it, you must have a starter on hand—one that’s been fermenting for a week. Below are tips and tricks for making a starter from food blogger Alanna Taylor-Tobin, as well as her recipe for sourdough bread from her site, The Bojon Gourmet.

This recipe makes one loaf (12 servings) and has 142 calories, 231mg sodium, 28g carbs, 2g fiber, 1g sugar and 5g protein per serving.

Starter Ingredients:

• ½ cup whole wheat flour
• ¼ cup water

Directions (by day):

1. Day 1: Mix ingredients in a jar with a spoon. Cover loosely with plastic wrap and let it rest in a warm spot, about7 5°F to 80ºF, for 24 hours.
   
   
2. Day 2: Check your starter for bubbles—even a couple will do! If you see a thin layer of dark liquid sitting on the top of your starter, skim it off. This is the “hooch,” and it’s not what we want in our bread. Cover it again and leave it be for another 24 hours.
   
   
3. Day 3: On the third day, your starter needs to be fed. Remove the top half of the starter from the jar and throw it out. Add ½ cup flour and ¼ cup water to the jar and mix it with the remaining starter with a fork. Cover and store in a warm place again for another 24 hours.
   
   
4. Days 4 – 6: On days four, five and six, you’re going to repeat the steps from the third day. Don’t forget to skim and discard the hooch every time.
   
   
5. Day 7: Your starter should be double the size it was the last time you checked on it, bubbly and the texture of a roasted marshmallow—nice and gooey. If not, you have to spend a few days more on the feeding process. Be patient, it’s worth it!

At this point, you’ve birthed a starter that you can take from and feed for years to come. Literally years. To test it and make sure it’s ready to use, drop a teeny dollop into a glass of water. Is it floating? Great, you’re ready to bake.

Sourdough Bread Ingredients:

• 12 ounces sourdough starter—active, bubbly and ready to go (about 1½ cups stirred down, or 3 cups at full froth)
• 8 ounces room-temperature or lukewarm water
• 1 ounce wheat germ 
• 5 ounces whole wheat bread flour 
• 8 - 10 ounces white bread flour 
• 1/4 ounces sea salt

Directions:

1. Stir all ingredients together in a large bowl until a rough dough forms. Add more bread flour if your dough is very wet.
   
   
2. Scrape the dough out onto a lightly floured surface. Invert the empty bowl over the dough and let it rest for 20 minutes.
   
   
3. Remove the bowl and knead the dough vigorously for about 10 minutes—adding as little flour as possible to prevent the dough from sticking to your hands and the surface—until it feels smooth, springy and elastic.
   
   
4. Place the dough in a large, lightly oiled bowl. Cover tightly with plastic wrap and allow it to rise until doubled, 3 to 4 hours. The warmer the spot you choose, the faster it will rise, the ideal temperature being 75°F to 85ºF. You can also let the dough rise in the fridge or a cool place overnight.
   
   
5. The dough should have doubled in size. Gently turn out onto a lightly floured surface. Tuck the edges underneath and then and gently rotate the dough on the surface to form a taut outer layer of dough. It’s called a boule, and Alanna has a video for this step here.
   
   
6. Place the boule directly on a peel or board dusted with flour, then slip the whole thing into a large plastic bag. Close the bag with a twist tie or clip while trying to preserve as much air inside the bag as possible. Let the bread rise until doubled, about 1½ to 2 hours.
   
   
7. While the bread is rising, place a baking stone (or heavy-duty baking pan) on the oven rack and place a metal pan that you don’t care about sacrificing (it will get rusty) on the floor of the oven. Crank the oven up to 500ºF. 
   
   
8. Poke the bread with your finger and see if the indentation holds. If so, you’re ready to bake! Gently turn it out onto a wooden peel dusted with flour. Fill a cup with ice cubes. Quickly slip the boule off the peel and onto the stone and toss the cubes onto the hot pan on the floor of the oven. This will steam the outside of the loaf, allowing it to expand as it bakes.
   
   
9. Bake for 20 minutes, then turn the oven down to 450ºF and bake another 20 minutes or so, until the bread is a deep golden-brown. An instant-read thermometer inserted into the middle should read 210ºF, the temperature at which the dough is set.
   
   
10. Let cool completely on a wire rack, 1 to 2 hours, before enjoying. And you will enjoy! 

Bread is best fresh but will keep in a paper bag at room temperature for up to three days.