Low GI bread helps manage blood sugar by releasing glucose slowly. Here’s a quick guide to the best options in Australia:

• Sourdough bread: GI 48–54. Benefits include better digestion and nutrient absorption. Rye sourdough is the lowest GI option.
• Whole grain & seed bread: GI 41–71. Look for dense, wholemeal-based breads with visible seeds for higher fibre and protein.
• Rye bread: GI ~49. Rich in fibre, it supports blood sugar control and reduces inflammation.‍
• Low GI specialty breads: Designed for glucose control, with whole grains, low added sugar, and high fibre.

Quick comparison

Tips for choosing low GI bread:

1. Look for the GI symbol on the packaging.
2. Ensure whole grains are the first ingredient.
3. Aim for at least 2 g of fibre per slice.
4. Pair with protein or healthy fats for better blood sugar control.

For managing blood sugar, opt for nutrient-dense wholemeal or speciality breads and enjoy them as part of a balanced diet.

Looking for more low-GI bread options? Check out our dietitian-approved guide to the top 10 low-GI breads for even more delicious and blood sugar-friendly choices.

1. Sourdough bread

Sourdough bread, with a GI of 54, has a lower glycaemic index compared to regular white bread (GI 71). This is largely due to its natural fermentation process, which creates a unique nutritional makeup. Let’s dive into how fermentation impacts sourdough’s benefits.

When sourdough is fermented for over 4 hours, FODMAPs (especially fructans) can be reduced by up to 90%, making it easier to digest.

Here’s a quick comparison of different sourdough types:

It’s worth noting that not all sourdough is created equal. In Australia, supermarket versions made with white flour may lack the nutritional benefits of genuine whole-grain sourdough, which provides added fibre B vitamins, iron, zinc, and magnesium.

A single slice of quality sourdough (around 2 oz or 60 g) typically offers:

• 6 g protein
• 29 g carbohydrates
• 1 g fibre
• 280 mg sodium

The fermentation process also slows starch digestion, which helps regulate blood sugar levels. Plus, it boosts nutrient absorption—iron, for example, can be absorbed up to eight times more effectively—making sourdough a smart option for managing blood sugar.

Want to learn more about how carbs and the glycaemic index affect your blood sugar? Check out our guide to carbohydrates and the glycaemic index for a detailed breakdown.

2. Whole grain and seed bread

Whole grain and seed breads, like sourdough, help control glucose release while offering a variety of nutrients. These breads are a smart low-GI choice, typically ranging from 41 to 71 on the glycaemic index—much lower than white bread's GI of 100. Opting for breads with wholemeal bases and visible seeds can further enhance their benefits for blood sugar stability.

To choose the best option, look for breads that:

• List "whole grain" as the first ingredient
• Contain at least 2 grams of fiber per serving
• Have a GI value of 55 or less
• Feature a dense texture with visible seeds and grains

For balanced nutrition, aim for bread portions that provide 20–30g of carbohydrates per two slices. Pairing whole grain bread with protein-rich foods like eggs or Greek yoghurt can further improve blood sugar response.

3. Rye bread

Rye bread stands out as a great option for managing blood sugar levels. Whole grain rye bread has a low glycaemic index, with scores around 49, making it a solid choice for those looking to stabilise blood sugar [10]. It’s also packed with fibre; wholegrain soft rye bread contains 10.6 g of fibre per 100 g, compared to 6 g per 100 g in wholemeal bread.

A Swedish study found that people eating whole grain rye products lost an additional 2.2 pounds and reduced body fat by 0.5% compared to those consuming refined wheat. They also had 28% lower levels of inflammatory markers.

A typical serving of wholegrain rye bread (36 g) provides 73 calories, 2.0 g of protein, 17.1 g of carbohydrates, 3.8 g of dietary fibre and 115 mg of sodium.

To get the most benefits, look for rye breads made with whole grain rye flour as the main ingredient. Aim for options with more than 5 g of fibre per serving and less than 300 mg of sodium. Avoid commercial varieties that use refined flours or added sugars, as these can increase the glycaemic index.

Clinical studies also reveal that rye bread may lower total cholesterol by up to 14% and LDL cholesterol by 12%. Additionally, it helps people feel fuller and consume fewer calories compared to refined wheat bread.

4. Low GI speciality breads

Low GI speciality breads go beyond standard whole grain options by including ingredients specifically chosen to help manage blood sugar levels. These breads are designed to release glucose more gradually, making them a great addition to a fibre-rich diet.

What makes these breads stand out? They typically combine whole grains, both soluble and insoluble fibre, and healthy fats. This mix slows digestion and helps keep blood sugar levels steady. When shopping for these breads, keep an eye out for:

• A certified GI symbol to confirm low glycaemic index.
• Whole grains as the first ingredient on the label.
• At least 3 grams of fibre per slice for added nutritional value.
• Low added sugars, ideally between 1–3 grams per slice

To get the most out of these breads, pair them with protein-rich foods or healthy fats. This combination can help further reduce blood sugar spikes and provide long-lasting energy. Adding these breads to your meals can support better blood sugar management while contributing to overall metabolic health.

Benefits and limitations

Choosing the right low GI bread can help you make better dietary decisions. Here's a comparison of popular low GI bread types, focusing on their nutritional content and effects on blood sugar:

That said, glycaemic index (GI) values aren't set in stone. They can change depending on factors like:

• Individual metabolic responses
• How the bread is prepared
• What other foods are eaten alongside it
• Portion sizes

‍Research underscores that glycaemic responses can vary significantly between individuals. To make the best choice, consider these tips:

• Look for a certified GI symbol to ensure the bread has been tested and meets low GI criteria.
• Check that whole grains are listed as the first ingredient.
• Aim for at least 2 g of dietary fibre per serving.
• Choose a bread with a balanced nutritional profile.

Incorporate low GI bread into a well-rounded diet that includes lean proteins, healthy fats, and vegetables to help maintain steady blood sugar levels.

Conclusion

Low-GI bread is an excellent choice for maintaining steady blood sugar levels, supporting digestive health, and providing long-lasting energy. With options like sourdough, whole grain, rye, and speciality low-GI varieties, you can enjoy bread without unwanted glucose spikes. The key is to focus on fibre-rich, minimally processed breads that contain whole grains as the primary ingredient.

"Choosing low-GI bread isn’t just about blood sugar control—it’s about long-term metabolic health. Opting for fibre-rich, whole grain options can support digestion, provide lasting energy, and contribute to overall well-being." — Charlotte Battle, Vively’s Lead Dietitian

Beyond glycaemic control, these breads offer additional benefits such as reducing inflammation, supporting heart health, and promoting satiety. Pairing them with protein or healthy fats further enhances their ability to slow digestion and stabilise glucose levels, making them a valuable part of a balanced diet.

For those looking to take a more personalised approach, Vively’s Continuous Glucose Monitor (CGM) can provide real-time insights into how different types of bread impact your blood sugar. By tracking your body’s unique response, you can make informed choices about which low-GI breads work best for you.