The glycemic index (GI) is a numerical value given to foods containing carbohydrates, based on how much they raise blood sugar, the University of Sydney says. The higher the GI value, the greater the food’s ability to increase blood sugar. Foods with a GI of 0 to 55 are considered low GI, those with a range of 56 to 69 are considered moderate, and foods with a GI over 70 are considered high GI. Most nuts are low- or moderate-GI foods, regardless of the variety, according to the University of Sydney.

Nuts are relatively low in digestible carbohydrates, so they have only a minimal to moderate effect on blood sugar (glucose) levels, research says. And nuts can even help lower the GI value of high-carbohydrate foods when they’re eaten together — the fiber, protein, and fats in nuts help slow the digestive breakdown of carbs into sugar, which slows the release of glucose into the bloodstream.

What’s the Glycemic Index Range for Nuts?

Nuts, in general, are a low-GI food, though some nuts are categorized as moderate-GI foods. The GI for nuts ranges from 5 for soaked, boiled, and reheated peanuts to 58 for steamed chestnuts, according to the University of Sydney. More common nuts, like regular peanuts, have a GI of 13, while cashews have a GI of 25.

Why Are Nuts Primarily a Low-Glycemic Index Food?

Nuts contain relatively small amounts of digestible carbohydrates — some of their carbs come in the form of fiber, which isn’t digested and broken down into glucose. Fiber helps reduce the amount of sugar released into the blood, research says. Low-GI foods are those with a score below 55; moderate-GI foods have a value between 56 and 69; high-GI foods have a value above 70.

Nuts are high in fat and protein. A 1-ounce serving of almonds contains 164 calories, including 6 g of protein, 14.1 g of fat, and 6.1 g of carbohydrates; 3.5 g of those carbs are fiber, according to the U.S. Department of Agriculture.

Most nuts are not a good source of digestible carbohydrates, which is why the impact of these crunchy, tasty snacks on blood glucose is typically low, research says. Because of their macronutrient makeup, nuts are a good complement to carbohydrate-rich foods. The fiber, protein, and fat in nuts slows digestion and absorption of the glucose created when carbs in other foods are broken down, essentially lowering the GI value of the high-carb foods.

Avoid Sweetened Nut Snacks to Keep GI Low

Nuts with added sweeteners, such as honey-roasted peanuts or candied pecans, will have a higher GI score. The score will still likely be less than eating carbohydrate-rich foods such as cookies and crackers with added sugar by themselves. This is because the nuts contain the fiber, protein, and fat that are crucial to managing blood glucose levels, research says.