Glycemic Index of Bread

Most bread is high GI. That includes most supermarket whole wheat, which tests at 74, about the same as white bread at 75. The breads that come in low are sourdough, pumpernickel, and dense loaves with whole kernels you can see.

Below are GI and GL values for 21 breads, the swaps that make the biggest difference, and a shopping list you can print.

• Bread GI table
• What makes bread lower
• Best and worst picks
• Smart swaps
• Shopping list
• Tips
• FAQ
• Printable

Glycemic index of bread: 21 breads compared

Sorted lowest to highest GI. GI: low 55 or less, medium 56–69, high 70+. GL per serving: low 10 or less, medium 11–19, high 20+. No bread fits keto or Atkins Phase 1.

Other baked goods

Cakes can test low because fat and sugar (fructose) slow the rise in blood sugar. A low GI doesn’t make them a good everyday choice; most still carry a medium or high GL.

What makes one bread lower than another

Whether the label says white or wheat matters less than these four things:

How finely the grain is milled. Flour digests fast whether it’s white or whole wheat. Bread made with whole or cracked kernels digests slower. That’s why whole-grain kernel bread tests at 50 and supermarket whole wheat at 74.

Fermentation. The acids in sourdough slow digestion. Wheat flour tests at 54 as sourdough and 75 as regular yeasted white bread.

Density. Heavy, compact breads like pumpernickel break down slowly. Light, airy breads like baguette (95) are the opposite.

Portion size. Size doesn’t change GI, but it changes GL. A bagel weighs as much as two and a half slices of bread, so its GL (25) is more than double a slice of white bread (11).

One caution: the flour tortilla’s low score (30) comes from a single published test. Treat it as a reasonable option, and watch the size. A burrito-size wrap carries two to three times the carbs of the 50 g serving above.

Best and worst picks

Smart swaps

Low-GI bread shopping list

• Sourdough, wheat or rye
• Pumpernickel
• Dense multigrain with visible seeds
• Whole-grain kernel bread
• Corn tortillas
• Chapati or roti
• Small flour tortillas

Reading the label:

• “Whole wheat” or “made with whole grains” doesn’t mean low GI. Look for kernels you can actually see.
• For rye, whole rye or rye flour should be the first ingredient. Light rye that’s mostly wheat flour tests at 64.
• Real sourdough lists a starter or culture. Some “sourdough-style” loaves are regular bread with added flavoring.
• Heavier for its size is usually better. A dense slice means more intact grain.

Tips to help you succeed

• Pair bread with protein or fat. I rarely eat bread on its own. Eggs, cheese, nut butter, or avocado slow how fast the carbs reach your bloodstream.
• Make it an open sandwich. I usually skip the top slice. One slice instead of two cuts the GL in half.
• Freeze, then toast. I keep a sliced sourdough loaf in the freezer and toast slices straight from frozen. Besides being convenient, it may help: in a small study, white bread that was frozen, thawed, and toasted raised blood sugar noticeably less than fresh bread. It won’t turn white bread into a low-GI food, though.
• Watch the bagel and the wrap. Large bagels and burrito-size tortillas can carry 50–60 g of carbs, two to three times a standard serving.

How I shop for bread

I go by feel more than the front of the package. If a loaf is heavy for its size and I can see whole grains or seeds in the slice, it usually lands in the low range. For everyday sandwiches I buy sourdough rye or pumpernickel, and I keep corn tortillas on hand for tacos instead of crisp shells. Bagels and baguettes are an occasional treat, not a breakfast habit.

Frequently asked questions

What is the lowest glycemic bread?

Of breads with published tests, sourdough rye, dense multigrain, pumpernickel, and whole-grain kernel bread all score 48 to 50. Flour tortillas tested lower (30), but that’s a single test, and tortilla sizes vary widely.

Is sourdough bread low glycemic?

Yes. Wheat sourdough averages about 54, at the top of the low range, and rye sourdough about 48. Results run from 54 to 73 depending on the recipe, so a dense, tangy loaf is a safer bet than a soft one.

Is whole wheat bread low glycemic?

Usually not. Most supermarket whole wheat tests around 74, close to white bread at 75, because the flour is milled just as fine. Its advantage over white is fiber, not a lower GI.

Is rye bread good for blood sugar?

It depends on the rye. Pumpernickel and sourdough rye score 48 to 50. Light deli rye, which is often mostly wheat flour, scores about 64.

Can you eat bread on South Beach or keto?

South Beach Phase 1 excludes all bread. From Phase 2, low-GI breads like sourdough, pumpernickel, and whole-grain kernel bread are back in moderation. No bread fits keto or Atkins Phase 1: a single slice uses more than half of a 20 g daily carb limit.

Does toasting bread lower its GI?

Somewhat. Freezing and toasting each lowered the blood sugar response to white bread in a small study, and doing both had the biggest effect. Starting with a low-GI bread still makes the bigger difference.

Printable bread list

A free one-page version of this list is coming soon. For the full printable set covering every food group, see the glycemic index food lists at Health List Now.

GI values vary between tests. This page is general information, not medical advice. Last reviewed October 2026.