Natural Sourdough Bread
The authentic artisan loaf with a crisp crust and a chewy, open crumb full of air pockets: naturally fermented for 24 to 48 hours by wild yeasts and lactic acid bacteria without commercial yeast. The long fermentation breaks down part of the starch, giving it a low glycemic index (≈53) and much calmer digestion than ordinary white bread.
Glycemic index
Glycemic load
Calories
Protein
💡 Smart Nutritional Guidance
Consumption advice
One toasted slice with boiled egg and avocado or olive oil is an ideal combination that slows carbohydrate absorption and keeps you full until midday.
Best preparation methods
Toast your sourdough slice; toasting partly changes how fast its starch breaks down, and enjoy its delicious tangy flavour that gives a wonderful feeling of fullness.
Important Nutritional Note
The lactic acid bacteria in sourdough break down a large part of the gluten and phytic acid, making it easier to digest and its minerals (such as zinc and magnesium) more available; it still contains gluten, however, and is not suitable for people with a true wheat allergy.
Nutrition facts
| Nutrient | Per 100 g | Per typical portion (40 g) |
|---|---|---|
| Calories | 230 kcal | 92 kcal |
| Protein | 8.5 g | 3.4 g |
| Carbohydrate | 45 g | 18 g |
| Available carbohydrate | 41.5 g | 16.6 g |
| Fat | 1.2 g | 0.5 g |
| Dietary fibre | 3.5 g | 1.4 g |
The typical portion is approximate, for comparison purposes.
Comparison & smarter alternatives
Among the foods in Grains & starches with a glycemic index (35), it ranks 16 (lowest first).
Smart alternatives from the same family:
Frequently asked questions
Is Natural Sourdough Bread good for weight loss?
It can be included in moderation: it contains 3.5 g of fibre per 100 g, which supports fullness, and a 40 g portion gives 92 kcal.
How does Natural Sourdough Bread affect blood sugar?
Its glycemic index is 53 (Low), a clinically reviewed estimate rather than a laboratory measurement. A typical 40 g portion has a glycemic load of 8.8 (Low), so the effect of this portion on blood sugar is limited.
What is the nutritional value of a typical portion of Natural Sourdough Bread?
A typical 40 g portion of Natural Sourdough Bread provides about 92 kcal, 3.4 g protein, 18 g carbohydrate, 0.5 g fat and 1.4 g fibre.
Reviewed by the WiBo Health medical team · Last reviewed 13 October 2026
Disclaimer: This guidance is for nutritional lifestyle orientation and does not constitute a diagnostic medical device under EU Regulation MDR 2017/745.