In general, slow-release carbs are found in foods that contain more fiber, longer chains of starch, no added sugar, and limited natural sugar.
But, what are slow carbs? What is the difference between slow digesting carbs vs fast digesting carbs? What are some of the best slow release carbs that you should include in your diet?
In this article, we will discuss what slow release carbs are, the benefits of eating slow digesting carbs, and the differences between slow carbs vs fast release carbs. We will also provide a slow release carb food list to help you choose the best slow carbs to add to your diet.
We will cover the following:
- What Are Slow Carbs?
- What Are the Benefits of Eating Slow Release Carbs vs Simple Carbs?
- What Are the Best Slow Digesting Carbs to Eat?
Let’s dive in!
What Are Slow Carbs?
Slow release carbs, also called slow digesting carbs or slow carbs, are a subset of carbohydrates that take longer to digest, resulting in a slower release of glucose (sugar) into the bloodstream.
Carbohydrates are one of the three primary macronutrients, alongside proteins and fats.
Slow-release carbs can be seen as the opposite of simple carbohydrates, simple sugars, or what is sometimes called fast digesting carbs, all of which essentially refer to foods that are high in carbohydrates and are readily and rapidly digested and absorbed after consumption, causing a quick increase in blood sugar.
Slow carbs are considered to be those with a glycemic index of 55 or less. A glycemic index score of 56–69 is medium glycemic food, and high-glycemic foods (simple sugars and refined grains) have a GI of 70 or above.
For reference, the glycemic index ranges from 0-100, with 100 being the maximal, rapid blood sugar spike that can come from eating simple sugars like white sugar.
What Are the Benefits of Eating Slow Release Carbs vs Simple Carbs?
Consuming slow digesting carbs can be a great way to take advantage of the health benefits of nutrient-dense carbohydrates like whole grains, legumes, and vegetables while avoiding unhealthy refined carbohydrates that can cause blood sugar spikes.
Essentially, slow digesting carbs help keep your blood sugars stable because the carbohydrates within them take longer to break down. This means that the sugars that are eventually yielded are released more slowly into the bloodstream rather than all at once.
This also helps prevent a spike in insulin.
Over time, diets that contain a lot of simple sugars and refined carbs have been shown to cause weight gain and an elevated risk of obesity, type 2 diabetes, insulin resistance, metabolic syndrome, heart disease, and stroke.
What Are the Best Slow Digesting Carbs to Eat?
It would be virtually impossible to provide a complete list of slow release carbs.
However, to help you choose some of the best slow carbs for sustained energy to add to your diet we have broken down some slow-carb foods for various food groups give you some examples and direction when choosing which slow digesting carbs to eat.
Here are some examples of slow digesting carbs in different food groups:
#1: Cereals and Grains
Many breakfast cereals and grains are fast-acting carbs because they contain added sugar, as in the case of breakfast cereals like Honey Nut Cheerios, Lucky Charms, and sweetened oatmeal packets.
Similarly, refined grains such as white pasta, white rice, white bread, couscous, white bagels, pop tarts, crackers, pretzels, and even unsweetened but refined cereals such as cornflakes, are also fast-acting carbs or simple carbohydrates.
This is because the refining and milling process strips these grains of fiber and ultimately leaves a carbohydrates-rich food that acts as simple sugars, even if the number of grams of added sugar may be minimal.
For example, according to the American Diabetes Association (ADA), white bread has a GI score of 73–77.
The glycemic index was developed by a Canadian professor, Dr. David Jenkins, in the early 1980s. It has since been used and expanded upon as more carbohydrate-based foods have been studied and compared to the absorption rate of pure glucose.
So, what are some slow-release carbs that are grains or cereals?
Rolled Oats
Rolled oats oatmeal has a GI score of 55 because the oats are in a more whole-grain state with the bran still attached. This means that the fiber, such as a beta-glucan, and long polysaccharide chains of starch are still intact.
Breaking down these nutrients takes much longer than breaking down the carbs in quick oats.
For example, because quick oats are heavily refined, the bran/fiber has been removed, and the milling process has already reduced the complex nature of the carbohydrate molecules, leaving just simple carbs.
Quinoa
Quinoa is technically a seed but is a cereal grain that is used as a rice or pasta analog. Quinoa provides a complete source of protein, with all the essential amino acids, along with essential nutrients like potassium, iron, and the vitamin B complex.
Due to the fiber and protein content, quinoa is a slow digesting carb that takes time to process, resulting in a glycemic index value of just 53.
This means that if you want to eat a portion of nutritious whole-grain food but do not want a significant spike in your blood sugar or insulin, quinoa can be a healthy grain option.
#2: Vegetables
In general, the best food sources for slow digesting carbs are vegetables.
Vegetables are slow digesting carbs because most vegetables contain cellulose, ligands, or other types of fiber that take longer to break down and digest.
This makes many vegetables low-glycemic foods because the longer digestion process leads to a more gradual release of glucose into the bloodstream.
With that said, there are some starchy vegetables and high fructose vegetables that buck this trend and are considered fast digesting carbs with a higher glycemic index value.
To this end, cooking vegetables for a long period of time generally increases the glycemic index score because the heating process largely, or at least partially, degrades the cellulose, other fiber, and longer chains of complex carbohydrates.
This eliminates the need for your own digestive system to break down these complex molecules, resulting in much quicker digestion and absorption of the sugars and a more rapid increase in blood glucose.
Some of the slowest release carbs from vegetable sources include vegetables with a high-water content and low-sugar content, such as asparagus, artichokes, spinach, lettuce, bean sprouts, kale, cauliflower, broccoli, sunchokes, cucumbers, zucchini, Swiss chard, bok choy, mushrooms, onions, and bell peppers.
Even many vegetables that are typically considered starchy vegetables or high-sugar vegetables are still generally slow carb foods, particularly if they are eaten raw or lightly steamed.
Examples include carrots, parsnips, sweet potatoes, butternut squash, and yams. Even sweet corn has a GI value of just 55, and the aforementioned starchy vegetables are all even lower than this.
#3: Legumes
Legumes are foods such as beans, peas, chickpeas, peanuts, and soybeans.
All of these foods are high-carb foods, but they are slow-release carbs because the fiber content and molecular structure of the carbohydrates are complex. Legumes also contain quite a bit of plant-based protein, which also slows the degradation and absorption process.
Ultimately, the nutritional profile of legumes leads to a long digestion process and a very slow and gradual release of sugar into the bloodstream.
As a result, most legumes have a glycemic index value of less than 50.
For example, kidney beans have a glycemic index score of just 19, red lentils are 21 on the glycemic index, chickpeas have a GI value of 36, and pinto beans have a GI score of 33.
As a result, legumes can help you feel fuller for longer and may thus aid in weight loss.
#4: Fruits
Most people assume that all fruits are high glycemic foods and fast digesting carbs because fruits contain natural sugars such as fructose.
However, some fruits are slow-release carbs because the water and fiber in the fruits take time to process, leading to a titrated release of glucose into the bloodstream.
As a general rule of thumb, tropical fruits are fast-acting carbs with a higher glycemic index value, whereas berries, melons, and stone fruits tend to be slower-release carbs.
For example, the glycemic index value of plums is 24, grapefruit is 25, peaches have a G score of 28, apricots have a GI value of 34, apples and oranges, as well as strawberries all have a glycemic index value of 40, and pears have a GI score of 42.
In contrast, watermelon has a GI score of 80, pineapple is also a high-glycemic index food with a GI value of 66, and mango and papaya are similar.
You can find the glycemic index of different foods in this database.
To learn more about healthy carbohydrates, check out our guide to fibrous carbs here.
