Which is better for diabetics, barley or oats?: A Nutritional Deep Dive

October 5, 2025 •

4 min read

A diet rich in whole grains is a cornerstone of managing diabetes effectively, thanks to the fiber content that helps regulate blood sugar. When comparing two popular choices, a common question arises: which is better for diabetics, barley or oats? The answer involves looking closely at their nutritional profiles, particularly their glycemic index and soluble fiber content, to see how they impact glucose levels.

Quick Summary

Both barley and oats offer significant benefits for blood sugar management, primarily due to their high soluble fiber content. Barley typically has a lower glycemic index, while oats are naturally gluten-free. The optimal choice depends on individual dietary needs, preferences, and proper preparation to maximize health benefits for diabetics.

Key Points

Barley's Lower GI: Hulled barley has a lower glycemic index than any form of oats, leading to more stable post-meal blood sugar levels.
Beta-Glucan Benefits: Both barley and oats are rich in beta-glucan, a soluble fiber that slows digestion and improves glycemic control and cholesterol levels.
Processing Matters Most: The level of processing is critical; minimally processed versions (hulled barley, steel-cut oats) are far superior for diabetics than refined or instant options.
Gluten-Free Choice: Oats are a naturally gluten-free grain, making them a safe choice for diabetics with celiac disease, unlike barley which contains gluten.
Dietary Versatility: Both grains can be used in a variety of dishes, from hot porridge to savory soups and salads, offering flexibility in a diabetic meal plan.
Portion Control is Key: Despite their benefits, both are carbohydrates. Portion control is essential to manage total carbohydrate intake and prevent spikes in blood sugar.

For individuals with diabetes, managing blood sugar levels is a daily priority. The foods we choose can have a profound impact, and incorporating high-fiber, low-glycemic-index whole grains is a recommended strategy. Barley and oats are two such grains, both celebrated for their health benefits. But how do they compare head-to-head when it comes to regulating blood sugar? This article breaks down the science, nutrition, and practical considerations to help you decide which grain best fits your diabetes management plan.

The Crucial Role of Fiber and Glycemic Index

The glycemic index (GI) is a system that ranks carbohydrates based on how quickly they raise blood sugar levels after eating. For diabetics, choosing foods with a lower GI is vital to prevent blood sugar spikes and maintain more stable glucose levels throughout the day. This is where dietary fiber plays a critical role.

Both barley and oats are excellent sources of dietary fiber, especially a soluble type called beta-glucan. This fiber is particularly beneficial because it forms a viscous, gel-like substance in the digestive tract. This gel slows down the digestion and absorption of carbohydrates, leading to a more gradual increase in blood glucose and insulin levels. This effect is key to better glycemic control and is why both grains are highly recommended for a diabetic-friendly diet.

Barley vs. Oats: A Comparison for Diabetics

To make an informed decision, it is helpful to compare barley and oats across several key metrics.


Feature	Barley	Oats
Glycemic Index (GI)	Typically very low (around 28 for hulled).	Varies by type; steel-cut is low (around 55), while instant can be high.
Total Fiber	Can be richer in total fiber than oats, especially hulled varieties.	High in fiber, particularly soluble beta-glucan.
Beta-Glucan	A significant source; some studies suggest slightly higher content than oats.	Contains high amounts of beta-glucan, with confirmed health benefits for blood sugar and cholesterol.
Processing Type	Hulled barley is a whole grain; pearled barley is refined with some fiber removed.	Steel-cut is minimally processed; rolled is moderately processed; instant is highly processed.
Gluten Content	Contains gluten and is not suitable for people with celiac disease.	Naturally gluten-free, though check for processing contamination if you have celiac disease.
Preparation	Has a chewy texture and takes longer to cook than oats (especially hulled).	Versatile; cooking time varies from instant to steel-cut.

Barley: The Glycemic Index Winner

For those prioritizing the lowest GI, barley has a clear advantage. A study comparing the effect of barley and oats on post-meal blood glucose responses in overweight women found that barley was significantly more effective at reducing both blood sugar and insulin levels. This is primarily due to barley’s lower GI and high concentration of soluble fiber, which slows glucose absorption more effectively than some oat products.

When choosing barley, the type matters immensely. Hulled barley is a true whole grain with the highest fiber content, while pearled barley has had the fiber-rich bran removed, giving it a higher GI and less nutritional benefit. Always opt for the hulled variety when possible.

Oats: A Versatile, Gluten-Free Option

While oats have a slightly higher GI than barley, they remain an excellent choice for diabetics, especially when minimally processed. Steel-cut oats, which are the least processed, have a low GI and provide a steady release of energy. Their rich beta-glucan content is highly effective at improving insulin sensitivity and lowering cholesterol, which is a major concern for many people with diabetes.

Another significant benefit is that pure oats are naturally gluten-free. This makes them a safe and healthy alternative for diabetics who also have celiac disease or gluten intolerance. Just be sure to purchase oats certified gluten-free to avoid cross-contamination during processing.

How to Incorporate Them Into Your Diet

Maximizing the blood sugar benefits of these grains means controlling portions and avoiding sugary additions. Here are some ideas for including them in your meal plan:

For Barley:

Barley Porridge: Cook hulled barley until soft and creamy for a filling, low-GI breakfast.
Hearty Soups and Stews: Use barley instead of noodles or rice to add a chewy texture and boost fiber content.
Grain Salad: Mix cooked and cooled barley with vegetables, herbs, and a light vinaigrette.
Barley Pilaf: Prepare it as a side dish in place of white rice.

For Oats:

Steel-Cut Oatmeal: Prepare a slow-cooked oatmeal and top with nuts, seeds, and a sprinkle of cinnamon for enhanced blood sugar control.
Savory Oats: Make a savory oat bowl with sauteed mushrooms, spinach, and a poached egg.
Overnight Oats: Soak rolled oats in milk or yogurt with chia seeds and berries for a quick, grab-and-go breakfast.
Oat Flour: Use oat flour in baking pancakes or muffins for a high-fiber alternative to refined flour.

The Final Verdict: How to Choose

Ultimately, there is no single best grain for all diabetics. Both barley and oats offer powerful health benefits that support stable blood sugar. Your choice should depend on your specific health needs and preferences:

Choose Barley if... you are looking for the grain with the lowest glycemic index. Its excellent performance in controlling post-meal blood sugar and insulin spikes makes it a top contender, provided you select minimally processed hulled barley.
Choose Oats if... you have a gluten sensitivity or need a more versatile, faster-cooking breakfast option. Opting for steel-cut or rolled oats over instant varieties is crucial for maximizing benefits.

The most important factor, regardless of your choice, is consistency in eating whole, minimally processed grains. The American Diabetes Association (ADA) recommends both grains as excellent choices to include in a balanced diet. By focusing on portion control and opting for the least processed form, you can effectively use either barley or oats to help manage your blood sugar and support overall health.

For more detailed information on managing diabetes through diet, you can refer to the American Diabetes Association's nutritional guidelines.

Frequently Asked Questions

Hulled barley is significantly better for diabetics because it is a whole grain that contains the fiber-rich bran layer. Pearled barley has been refined, with the bran removed, resulting in a higher glycemic index and less nutritional benefit.

While it's best to prioritize less processed options like steel-cut or rolled oats, instant oats can be eaten in moderation. However, they are highly processed and have a higher GI, which can lead to larger blood sugar spikes. Always check the label for added sugars.

The soluble fiber, beta-glucan, found in both grains forms a gel in the digestive system. This gel slows down the absorption of carbohydrates, leading to a more gradual rise in blood sugar and insulin after meals.

Yes, both grains contain beta-glucan, which has been shown to lower total and LDL ("bad") cholesterol levels. This is especially beneficial for diabetics, who are at a higher risk of heart disease.

Oats, particularly rolled or instant oats, cook much faster than hulled barley. Steel-cut oats take longer than rolled oats but are still quicker than cooking hulled barley from scratch.

Drinking water in which barley has been cooked can provide some nutrients and fiber, which may help regulate blood glucose levels. However, consuming the whole grain is most effective for maximizing the benefits of its fiber and nutrient content.

No, barley contains gluten and should be avoided by individuals with celiac disease or gluten intolerance. In contrast, oats are naturally gluten-free, though certified gluten-free options are recommended to prevent cross-contamination.