Resistant Starch: Everything You Need to Know

Resistant starch is a compound present in rice, legumes, and tubers that promotes the growth of the microbiota. Learn more today!
Resistant Starch: Everything You Need to Know
Saúl Sánchez

Written and verified by el nutricionista Saúl Sánchez.

Last update: 01 January, 2023

Resistant starch is a compound present in certain foods of plant origin that could be very beneficial for the body, so it must appear in the diet frequently. It’s a type of soluble fiber that ferments in the digestive tract, serving as an energetic substrate for the bacteria that make up the microbiota.

Maintaining a competent microbiota greatly reduces the risk of developing complex diseases in the medium and long term. The optimal use of nutrients will be achieved and the balance will be maintained at the inflammatory level, thus managing to control the production of free radicals.

The importance of the microbiota in health

To really understand the benefits of resistant starch, it’s first necessary to emphasize the need to take care of the microbiota. The bacteria that inhabit the digestive tract fulfill several different functions.

On the one hand, they participate in the processes of digestion, absorption, and metabolism of food and nutrients. This ensures that the physiological reactions that have to be carried out in the internal environment are completed in a solvent manner.

Likewise, the set of bacteria constitutes one of the first lines of defense of the immune system. It controls the access of toxins and pathogens to the bloodstream, which helps prevent the development of infectious and chronic diseases. This is evidenced by research published in the journal Cell.

The microbiota can be negatively modified by several factors. The consumption of toxins such as alcohol will affect you. Also, the presence of trans fats will cause harmful changes.

The continued use of antibiotics, the lack of fermented products in the diet, and breastfeeding for less than 12 months may be risk factors for the development of dysbiosis.

But what’s determinant on a dietary level is a sufficient intake of fiber of at least 25 grams each day. This is corroborated by a study published in the journal Nature Reviews.

This is a substance that’s capable of increasing the volume of the fecal bolus and thus stimulating the mechanoreceptors of the intestine. It also serves as an energy substrate for the microorganisms that inhabit the digestive tract, preventing their density from lowering.

Resistant starch and microbiota

Resistant starch is a type of fiber, so its consumption will be vital for the microbiota. It falls within the group of soluble fibers, capable of retaining water and serving as a substrate for microorganisms.

Other examples of these compounds would be the pectins present in apples and the characteristic beta-glucans found in oats. Both have shown health benefits.

It’s key to note that these compounds are classified as carbohydrates, but they’re not digestible. They undergo a fermentation process inside the intestine from which other positive substances for health can be synthesized, such as short-chain fatty acids. These boast antioxidant capabilities.

After all, these compounds are decisive in maintaining the inflammatory balance in the internal environment. This prevents an excessive generation of free radicals and superoxides that may interfere with mitochondrial function and genetic replication processes.

For the fermentation process from resistant starch and other fibers to really take place, it will be crucial for the profile of bacteria that inhabits the digestive tract to be optimal. This is achieved above all by including fermented foods in the diet, such as yogurt and kefir.

One could also opt for the inclusion of probiotic supplements in the regimen, although it’s not always easy to choose the correct one. It’s important to look at the labels to verify the strains used and the number of colony-forming units.

Where is resistant starch found?

Rice contains resistant startch.
There are many common consumer products that contain resistant starch, such as white rice.

In general, resistant starch is found in foods with carbohydrates that are eaten cold. The theory is simple. When cooking, the structural links of the sugars vary, causing them to be indigestible by the human body after cooling. This will favor the subsequent fermentation processes, thus achieving the aforementioned benefit.

For this reason, the best way to include sufficient amounts of fermented starch in the diet is to eat cold cooked rice or cold cooked potatoes. You can cook it the day before and leave it in the fridge for later consumption.

This will lower your glycemic index, causing less of an impact on blood sugar levels. This is considered very good in order to prevent diseases such as diabetes.

According to research published in the journal Oxidative Medicine and Cellular Longevity, the consumption of resistant starch could be a positive strategy to control this type of metabolic disease.

Today, we know that type 2 diabetes is a reversible disease, as long as a series of interventions are carried out in lifestyle habits and are maintained over time.

Now, you always have to be careful with excessive fiber consumption, as it’s considered an antinutrient. It can partially block the absorption of certain minerals, generating deficits in the medium term. It’s not particularly common, but it can happen.

Resistant starch and inflammatory diseases

It’s clear that resistant starch can generate a series of benefits in healthy individuals and in the context of certain diseases. However, it may be necessary to restrict its consumption when there is an inflammatory bowel disease or a dysbiosis process.

In these cases, bacterial overgrowths of pathogens usually occur. After all, fiber isn’t selective when it comes to promoting the growth of microorganisms, so the symptoms could increase.

In these contexts, what’s crucial is following a very low-fiber diet for 4 or 6 weeks while including probiotics to restructure the microbiota profile.

Then, it consists of reintroducing fiber progressively with the aim of increasing the fixation of the new microorganisms, thus generating a benefit in the host. In the most severe cases, antibiotic treatment may even be necessary.

These are situations with a certain level of severity and symptomatic expression. The inclusion of resistant starch on a regular basis in the diet will be crucial to prevent their development, greatly improving the density of the bacteria that inhabit the digestive tract.

Especially in combination with fermented foods such as yogurt, the effects will be even better. A study published in the Critical Reviews in Biotechnology magazine corroborates this.

How to prepare resistant starch?

Cooking utensils and a bottle of olive oil.
With a little creativity, you can make various culinary preparations that include a significant amount of resistant starch.

We’re now going to offer a method for preparing food with resistant starch. In this case, we’ll use potatoes or sweet potatoes that have to be cooked in the oven and with their skin on so that none of the water from the starch is lost. It’s important not to break the tubers into small pieces, otherwise, too much surface area will be exposed.

Once they’re cooked, you should allow them to cool. But what’s really interesting, rather than consuming them cold, reheating them later. This will achieve a more effective subsequent glycemic control, due to a greater effect on the part of the fibers. Thanks to this, metabolic alterations such as insulin resistance, characteristic of people with type 2 diabetes, will be avoided.

Resistant starch, a beneficial fiber

Resistant starch is a compound present in foods such as rice or tubers that originates from a series of certain cooking mechanisms. It manages to improve the growth of bacteria that inhabit the digestive tract and facilitate the management of diseases such as type 2 diabetes. For this reason, its frequent inclusion in the diet is recommended.

Many compounds that function as prebiotics can be found in regular consumer products. Examples would be pectins and beta-glucans. Their combination with foods that have undergone fermentation is positive, as is the case with yogurt, in order to achieve a superior effect on a microbiota level. Thanks to this, dysbiosis processes that affect a person’s well-being will be avoided in the future.



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