Resistant Starch: What Is It and How It Aids Weight Control?

November 18, 2022

Resistant starch is created when we store cooked food rich in starch such as pasta, rice, or potatoes in the refrigerator for at least 24 hours. It is a great prebiotic and reduces the amount of digestible sugars in food.

Resistant starch: what is it, and what are its health benefits?

Starch is a type of complex carbohydrate present in cereals, tubers, or legumes.

Resistant starch is a good ally to take care of intestinal flora or to reduce the contribution of sugars in food. We will explain what exactly resistant starch is, how you can obtain it, and the benefits it brings to your health and weight control. 

What is starch and which foods provide it?

Starch is a type of complex carbohydrate present in starchy foods (they contain starch or similar substances). 

  • Cereals and cereal products such as rice, quinoa, buckwheat, amaranth, and pasta. 

  • Tubers and root vegetables such as potatoes, sweet potatoes, turnips, cassava, carrots, and beets.

  • Legumes such as beans, peas, lima beans, etc.

When the food is raw, the starch could be compared to a string of pearls formed by thousands of glucose molecules that are compacted to form crystals that are impossible to digest, so it must undergo a cooking process. 

When the food is cooked, the water molecules bind to the glucose molecules in the starch, turning what were hard crystals into a kind of gel. 

This process of starch gelatinization is responsible for rice tripling in volume when boiled, or for pasta and legumes doubling in volume and weight.

Thus, starch is softened by cooking and becomes digestible, i.e., usable by the body. Once in the intestine, specific enzymes such as pancreatic alpha-amylase are responsible for breaking down the glucose so that it crosses the intestinal barrier and passes into the blood.

How is resistant starch formed?

Resistant starch is formed by storing starch-rich food for at least 24 hours in the refrigerator after cooking.

In the raw state, the starch is solid and hard as glass. Once cooked, the string of pearls (glucose molecules) acquires a gel-like texture and softens. But when we keep it in the refrigerator, after 24 hours, it begins to change its molecular structure and forms knots in that necklace or string of glucose. And with each passing day, more and more knots form, and the linear stretches get shorter and shorter.

How does resistant starch aid weight control? 

When we eat rice or pasta that has been in the fridge for a couple of days, the percentage of glucose that passes into the blood is lower than if we eat these dishes freshly cooked.

The reason is that the digestive enzymes cannot break the knots of the resistant starch, they can only break the linear sections to release the glucose molecules. Thus, a dish of macaroni that has been in the refrigerator for two days will give us fewer calories and be less fattening than if we eat it right away.

Do we create resistant starch if we freeze the food?

To create resistant starch, we must keep the food in the refrigerator for at least 24 hours but not freeze it. When we freeze food, it does not change its molecular structure, it only becomes immobile.


What are the health benefits of resistant starch?

Resistant starch is a prebiotic that improves intestinal flora. The knots of resistant starch are not digestible and once in the intestine, they serve as food for beneficial gut bacteria. 

The bacteria use these glucose molecules to ferment and obtain chemical energy that allows them to survive and multiply. Resistant starch is a great prebiotic comparable to fiber.

Resistant starch reduces the calories in food. When resistant starch is created, the amount of usable glucose provided by a starch-rich food is reduced because digestive enzymes cannot digest it completely. This is why resistant starch is a good ally for weight control.

Why is it advisable to rinse boiled pasta with cold water?

Although this is probably the worst thing to do from a culinary point of view, rinsing boiled pasta with cold water helps it remove all the unnecessary substances we don't want to ingest. 

Once boiled, the rice or pasta must be rinsed with cold water to eliminate the glucose remaining on the surface, making your food sticky. If we don't do it and keep the macaroni or rice for later, they will get sticky due to the excess glucose. 

Another reason why rinsing starch-rich foods with cold water is good is to avoid overcooking. 

If you rinse boiled rice or pasta with cold water, you will provoke a thermal shock that stops the food from continuous cooking. 

Food cooked al dente slows down the digestive process, so that glucose crosses the intestinal barrier little by little, avoiding spikes in blood sugar levels. 

Final Word

Resistant starch is best obtained from starchy foods after keeping them in the fridge for 24 hours. 

This type of starch aids weight control because it has lower glucose levels, thus helping you lower calorie intake while you still munch on your favorite Mac and cheese.