5 Best Whole Grains to Help Improve Insulin Resistance

Our bodies are designed to know how to digest food. For example, they break down carbs into glucose, the body’s preferred energy source. The pancreas then makes the hormone insulin and releases it to the bloodstream, supporting body cells to take up the glucose. 

Insulin resistance occurs when body cells ignore or don’t respond well to insulin, according to the National Institute of Diabetes and Digestive and Kidney Diseases. The glucose from food stays in the bloodstream, triggering the pancreas to make more insulin for the body cell receptors to respond and allow glucose to enter the cells. 

According to the National Library of Medicine’s resource, StatPearls, the National Health and Nutrition Examination Survey from 2021 estimates that 40% of U.S. adults ages 18 to 44 have insulin resistance. You may not even know you have insulin resistance unless you go for routine bloodwork to check your blood sugar levels, since you may or may not show symptoms related to the condition.  

High-carb foods are often under scrutiny when managing health. For example, cereals and grains come with the misconception that they are loaded with sugar and can spike blood sugar levels, potentially straining the body’s insulin response over time. However, we spoke with registered dietitians and certified diabetes educators who believe that eating certain high-carb foods in moderation, including whole grains and whole-grain cereals that are rich in fiber and protein with minimal added sugars, can be a viable part of a balanced diet for managing insulin resistance. Here are our five top whole grain picks for improving insulin resistance.

Oats

 Oats are an excellent source of soluble fiber, particularly beta-glucan, a type of soluble fiber shown in bodies of research to prevent blood sugar spikes, improve insulin sensitivity and lower LDL cholesterol. A clinical study from 2021 in the Journal of Functional Foods also found that eating 5 grams of beta-glucan from oats daily for 12 weeks significantly improved hemoglobin A1C, a marker for blood sugar control over three months.

According to the USDA, you will find almost 4 grams of beta-glucan in every 100-gram serving (about 3.5 ounces) of steel-cut oats. Beta-glucan also gives cooked oats their viscous and thick texture. Use oats as a binder in meat and veggie loaves, such as our Old-Fashioned Meatloaf, or to thicken the batter for light, fluffy Oatmeal Pancakes with Maple Fruit. 

Pulse oats into a breadcrumb-like texture, like panko, to coat meats. This is an excellent hack for added fiber and nutrients if you run out of whole-wheat panko for casseroles and baked chicken.

Barley

Barley is another whole grain full of soluble fiber. According to the USDA, barley flour contains over 4 grams of soluble fiber per 100-gram serving in the form of beta-glucan. A 2020 study from Clinical Nutrition Research noted that beta-glucan may positively impact post-meal blood glucose levels and promote insulin sensitivity (how efficiently your body responds to insulin), potentially due to it delaying digestion and absorption.

Barley makes an excellent side dish and a hearty addition to grain bowls, soups, stews and salads. It has a chewy texture that absorbs flavors well. Try to use hulled barley as opposed to pearled barley, as hulled barley contains more fiber than pearled.

Quinoa

Quinoa may not be the first grain that comes to mind when you think of fiber, but this fluffy-textured grain deserves the spotlight.  

A 2023 study published in Frontiers in Physiology involved 138 participants with impaired glucose intolerance who were randomly divided into control and quinoa-intervention groups as part of a one-year study. The researchers found that, compared to the control group, those with quinoa added as a staple to their intake had improved post-meal blood sugar levels and insulin sensitivity and delayed progression from impaired glucose tolerance to diabetes.  

These findings could be related to the whole grain’s fiber content, since it’s packed with 5 grams of fiber per 1-cup cooked serving, per the USDA. Quinoa’s also rich in plant protein, so you may feel full for longer since, like fiber, protein also helps slow down digestion.

Quinoa is delicious as a side dish, a base for salads and casseroles and an ingredient mixed into stir-fries. Because quinoa is mild in flavor, it can absorb sweeter notes from foods like carrots, cinnamon and raisins, or savory flavors with fresh herbs like parsley and dill. Peruse our healthy quinoa recipes for meal and snack inspirations!

Buckwheat Groats

Buckwheat groats, also known as kasha, are the seeds of the buckwheat plant. According to the USDA, 1 cup of cooked roasted groats offers almost 5 grams of fiber.

Including buckwheat groats as part of a balanced meal pattern could prevent the roller coaster of blood glucose levels, improving insulin sensitivity and reducing A1C, notes a 2023 Food Science & Nutrition review. 

Another review from 2022 in the Journal of Personalized Medicine indicates that eating buckwheat regularly may also be linked to lowered fasting blood glucose levels. 

Toasted whole buckwheat groats are nutty and crunchy, and when cooked, their texture is similar to rice. You can add buckwheat groats to porridges, granola, pancakes, salads, pilafs, risottos and meat dishes. If you’re looking for something on the sweeter side, make some filling muffins with roasted groats or our Buckwheat Pancakes.

Brown Rice

 While rice often gets a bad rap for raising blood sugar levels, there are reasons why brown rice is on our list. For starters, brown rice is a whole grain with 3 grams of fiber per 1-cup serving, according to the USDA.

While eating brown rice doesn’t appear to lower fasting blood sugar levels and improve A1C levels, it can help slow down the digestion and absorption of carbohydrates, contributing to lower post-meal glucose levels and improved insulin sensitivity, per a 2022 review from Comprehensive Reviews in Food Science and Food Safety.

Brown rice is a versatile ingredient with mild flavor. Use it as a base for savory rice bowls, pilafs and even desserts, like Mango Sticky Brown Rice. 

How Whole Grains Improve Insulin Resistance

While whole grains are rich in both soluble and insoluble fiber, soluble fiber may have a more pronounced effect in stabilizing blood sugar levels and increasing insulin sensitivity, per a 2025 study published in Food Research International.

When you eat whole-grain foods packed with soluble fiber, the fiber mixes with food by absorbing water and forming a gel. This gel-like property limits the food’s contact with the absorbent surfaces in the digestive tract, consequently slowing down digestion and how fast glucose is absorbed.

At the same time, soluble fiber ferments, prompting the production of short-chain fatty acids (SCFAs). SCFAs in turn cause the release of a digestive-related hormone called glucagon-like peptide-1 (GLP-1) in the intestines, per a 2025 study in Biomolecules.

“In response to food intake, [GLP-1] helps improve [glucose tolerance and] insulin sensitivity by enhancing insulin release and slowing stomach emptying to regulate blood sugar metabolism,” explains Michelle Routhenstein, M.S., RD, CDE, a registered dietitian and certified diabetes educator. Routhenstein also notes that fiber feeds the good bacteria in the gut.

Jonathan Valdez, M.B.A., RDN, CDN, CDCES, also a registered dietitian and certified diabetes educator, adds that gut-friendly bacteria produce SCFAs when they eat the fermented soluble fiber. SCFAs are then absorbed into the body, supporting the nerves involved with glucose and cholesterol regulation. A 2023 systematic review and meta-analysis from Nutrition Reviews concluded that eating foods with soluble fiber in moderation, including whole grains, may boost the production of SCFAs and improve insulin sensitivity.

Routhenstein suggests aiming for three to five servings of diverse whole grains daily, which can contribute to improved insulin sensitivity.

Other Tips to Lower Insulin Resistance

 While eating a variety of whole grains is key to combating insulin resistance, the complexity of the condition goes beyond this. Your overall diet, sleep, stress, lifestyle choices, genetics and more can play a role. Here are a few other tips to help lower insulin resistance.

• Include plant-based foods. There is evidence that incorporating a variety of plant-based foods may lower the risk of type 2 diabetes.
• Get and stay active. The American Diabetes Association states that when you’re active, your cells become more sensitive to insulin, helping it to work more effectively at lowering blood sugar. Start where you’re at and try to work up to at least 150 minutes of moderate activity each week. And remember, any amount of movement is better than no movement.
• Develop a sleep routine: A good night’s sleep is about more than just getting enough rest; it can also impact your body’s insulin sensitivity, according to a 2022 systematic review in Cureus. To get a restful night, develop a bedtime routine that can help you sleep soundly for seven to nine hours each night, such as keeping your room dark, limiting caffeine in the afternoon and evening and avoiding screen time before sleep.

Our Expert Take

Eating whole grains rich in soluble fiber, such as oats, barley, quinoa, buckwheat groats and brown rice in moderation and regularly, along with a diverse range of nutritious foods, may help improve insulin sensitivity. Keep in mind that addressing insulin resistance requires a multifaceted approach, including focusing on your activity level, sleeping habits and other lifestyle factors. Start the discussion with your healthcare practitioner or registered dietitian today!