To maintain healthy blood sugar levels, it’s important to eat the right foods. For example, eating carbohydrates, fiber, and healthy fats can help prevent blood sugar spikes. Sugary high-carbohydrate foods can make it more difficult to control your diabetes, says Dr. Deena Adimoolam, an assistant professor of medicine, endocrinology, diabetes, and bone disease at the Icahn School of Medicine at Mount Sinai.
What is the glycemic index?
By knowing the glycemic index of foods, you can make better dietary choices and better manage your diabetes. The glycemic index rates carbohydrates according to how quickly and how much they raise blood sugar, on a scale of 1 to 100.
In addition to their high fiber content, low-glycemic foods also have high amounts of vitamins and minerals that slow digestion and affect blood sugar levels more slowly. People with diabetes should try to eat more low-glycemic foods to avoid blood-sugar spikes.
It is also important if you have diabetes to track the carbs you have throughout the day and each meal, since eating foods with a high glycemic index will spike blood sugar levels. Even if you don’t have diabetes, eating high-glycemic foods increases your risk for Type 2 diabetes , heart disease, and obesity.
Below are a few examples of low-glycemic foods you can eat to prevent spikes in blood sugar.
As a result of being digested more slowly, whole grains such as brown rice will have a lesser effect on your blood sugar levels, Adimoolam says. That’s because whole grains contain more fiber.
Studies in Hormone and Metabolic Research in 2007 suggested eating a fiber-rich diet (more than 30 grams of fiber a day), including whole-grain products, could lower the risk of Type 2 diabetes.
Examples of whole grains include:
- Barley (GI = 22)
- Bulgur (G1 = 46)
- Buckwheat (GI = 49)
Fruits and Vegetables
Healthy carbohydrates that are rich in fiber can be found in fruits and vegetables. To maintain healthy blood-sugar levels, doctors recommend that people with diabetes consume five portions of fruits (two portions) and vegetables (three portions) each day – though you should speak to your doctor about a meal plan that suits your needs.
Adimoolam says that ripe fruits tend to have a higher glycemic index than less ripe fruits. Eating fruits with the skin can be more beneficial, since the skin contains more fiber and can help lower blood sugar levels.
All fruits contain nutrients, but dried fruit and fruit juice are more concentrated sources of natural sugars. If at all possible, select whole forms of fruit such as fresh or frozen.
People with diabetes can eat most vegetables without problem, but starchy vegetables like potatoes, sweet potatoes, and plantains contain high amounts of sugar and should be consumed in moderation.
Some examples of low glycemic fruits and vegetables include:
- Apples (GI = 40)
- Oranges (GI = 40)
- Broccoli (GI = 10)
People with diabetes can also benefit from oats due to their low glycemic index and high fiber content.
Research published in the journal Nutrients in 2015 found that eating whole oats with at least 3 grams of soluble fiber daily can improve insulin sensitivity in Type 2 diabetes patients.
Make sure to choose steel-cut or rolled oats, as these varieties of oatmeal are less processed, which means they absorb more slowly into your bloodstream. Avoid instant oatmeal with added sugar, and if you want to mix fruit or other ingredients into your oatmeal, make sure you consider how much sugar and carbs they might contain.
The nutrients and vitamins in nuts, such as vitamin E, omega-3 fatty acids, and magnesium, improve heart health and contribute to a balanced diet. Nuts are also low-glycemic, rich in fiber, and a healthy fat source.
In a 2011 study published in the Journal of the American College of Nutrition, consuming more than a quarter ounce of nuts a day decreased Type 2 diabetes risk factors, like body mass index and waist circumference.
The healthiest nuts for people with diabetes are:
- Almonds (GI = 20)
- Cashews (GI = 20)
- Peanuts (GI = 14)
Garlic may help control blood sugar by increasing insulin levels in the body, due to some of its compounds — including allicin, allyl propyl disulfide, and S-allyl cysteine sulfoxide — which increase insulin sensitivity.
According to a 2017 study published in Food and Nutrition Research, consuming between 0.05 grams and 1.5 grams of garlic (from supplements) a day was associated with decreased blood-glucose levels in Type 2 diabetes patients.
Spice up your foods with garlic powder or add some crushed garlic cloves when you’re cooking. However, if you plan on consuming a lot of garlic, you should consult your doctor because it can cause heartburn, nausea, and gas (plus, bad breath). Additionally, garlic may be harmful to people taking blood thinners.
The bottom line
When compared with foods high in fast-acting carbohydrates, such as those high in added sugars and refined grains, foods high in fiber, protein, and healthy fats are better for lowering blood sugar and managing diabetes. Using the glycemic index to determine which foods to eat can be helpful, but it’s important to remember that everyone reacts to foods differently.
“Some foods with a low glycemic index could cause blood sugar spikes more quickly than they would for another person,” Adimoolam explains. The level of blood sugar can also be affected by other factors, such as what medications the person is taking and what else he or she is eating.
Consult your doctor if you have diabetes or may be at risk for it so you can determine the right diet for you.