Eating healthier carbohydrates may help prevent a host of chronic conditions, especially diabetes, but it is also associated with a lower risk of heart disease and certain cancers.

One way to choose foods is with the glycemic index GI. This tool measures how much a food boosts blood sugar. The glycemic index rates the effect of a specific amount of a food on blood sugar compared with the same amount of pure glucose.

One with a GI of 95 acts like pure glucose. High glycemic foods result in a quick spike in insulin and blood sugar also known as blood glucose. Low glycemic foods have a slower, smaller effect. Using the glycemic index is easy: choose foods in the low GI category instead of those in the high GI category see below , and go easy on those in between.

To learn more about keeping your meals healthy and on track with Diabetes, read Healthy Eating for Type 2 Diabetes , a Special Health Report from Harvard Medical School.

In some cases, the GL contradicts the GI, giving some foods that have a high GI a low GL score. For example, though watermelon has a GI score of 74, the GL of a standard serving of watermelon is 4, which is considered low. This can be confusing for people who are using the GI to assess their diet's impact on blood sugar.

Even though the GI does have significant drawbacks, it has been shown to offer some health benefits. The GI ranks foods according to their impact on blood sugar levels.

Typically, the higher the GI, the greater the impact a food has on blood sugar. Most high-carb foods have a higher GI. This is because carbohydrates have the greatest impact on blood sugar. Studies show certain groups may benefit from following low-GI diets, including:.

Low-GI diets could benefit overall health as they generally reduce the intake of added sugar, ultra-processed foods, and refined carbs, all of which have a high GI. Foods that have a low GI include meat, poultry, eggs, nuts, beans, and some fruits and vegetables. Low-GI foods contain nutrients that help blunt their impact on blood sugar levels, such as fiber and protein.

Chicken, beef, fish, and eggs all have a GI of zero because they contain zero or very small amounts of carbohydrates and have a minimal effect on blood sugar levels. Protein-rich foods slow digestion, which increases feelings of fullness and slows the absorption of sugar into the bloodstream.

This is why it's commonly recommended that people with diabetes pair carbs with sources of protein. Consuming protein-rich foods before a high-carb food can also help reduce post-meal blood sugar spikes.

Increasing your overall protein intake and reducing your intake of high-GI carbs may help improve blood sugar control. Non-starchy vegetables are low in carbs and are usually high in fiber.

Like protein, fiber slows digestion and the absorption of sugar into the bloodstream. Studies show that high-fiber diets are beneficial for people with type 2 diabetes, obesity, and many other health conditions associated with high blood sugar levels.

Adding low-GI non-starchy vegetables to your diet can help increase your fiber intake, which is an easy way to promote healthy blood sugar control and feelings of fullness. Nuts and seeds are rich in plant-based protein and fiber, both of which can slow the absorption of sugar into the bloodstream.

Most nuts and seeds have a low GI, such as:. Studies show that increasing nut and seed intake may help improve health markers in people with diabetes, such as fasting blood sugar, insulin levels, and the long-term blood sugar control marker hemoglobin HbA1c.

Eating more nuts and seeds may also help lower post-meal blood sugar in people at risk for developing type 2 diabetes, such as those with prediabetes.

A recent study of 66 people with prediabetes found the participants who consumed 20 grams of almonds 30 minutes before each major meal for three months showed significant reductions in post-meal blood sugar, HbA1c, and insulin levels compared to a control group. The treatment also helped normalize blood sugar levels in a large number of the participants.

Though beans and lentils are high in carbs, they generally have a low GI due to their high concentration of plant-based protein and fiber, which helps offset post-meal blood sugar spikes.

Here is the GI of popular beans:. Increasing magnesium intake can be helpful for people with high blood sugar, as magnesium plays an important role in glycemic control. Studies show people with diabetes who have low blood levels of magnesium have poorer glycemic control compared to people who have higher magnesium levels.

Even though fruits are high in carbs, many fruits have a low GI and can promote healthy blood sugar levels. Research shows eating fresh fruit can help protect against the development of type 2 diabetes and also improve blood sugar control in people with type 2 diabetes.

A recent review of 19 studies concluded that increasing fruit intake reduced fasting blood glucose concentration in people with type 2 diabetes. Some examples of low GI fruit include:. Even if you have high blood sugar levels, adding fresh fruit to your diet could benefit your overall health and glycemic control.

Foods with a high GI are usually high in sugar and refined carbs and low in protein and fiber. Some examples of high-GI foods include:. Although some foods that have a high GI are low in nutrients, like white bread and candy, other high GI foods, like potatoes and watermelon, are nutritious and offer fiber, vitamins, minerals, and beneficial plant compounds that promote overall health.

Some health experts recommend that people who wish to lower their blood sugar levels and improve their health simply reduce their intake of foods known to significantly impact blood sugar and cause other health issues, regardless of their GI.

For example, rather than following a diet composed of low-GI foods, it may be easier to cut back on sweets, refined carbs, sugary beverages, fried foods, and fast food.

You can pair this with increasing your intake of vegetables, fruits, and protein- and fiber-rich foods. The glycemic index categorizes food based on its impact on blood sugar levels.

Foods like meat, poultry, eggs, nuts, beans, and some fruits and vegetables typically have a low glycemic index. These foods are low in carbohydrates or are high in protein and fiber, which can reduce blood sugar spikes.

Foods with a high glycemic index might include foods high in refined sugars and carbs, such as white bread and sugary drinks like soda. However, some foods with a high GI, such as watermelon and potatoes, might offer other beneficial nutrients.

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