Why Resistant Starch Is Good For You
Have you been hearing people talking about the benefits of resistant starch, but you're not sure exactly what it is or whether it's something you should be focusing on or not? Then you're in the right place.
Today we're going to be discussing everything from the basics of what resistance starch is. To more detailed topics such as its role in gut health and glycemic control. Let's jump in.
Hello everyone. My name is Katie Krejci and I am a gut health functional medicine dietitian at Oswald Digestive Clinic, where we help people improve and eliminate bothersome gut issues like gas, bloat, diarrhea, constipation, and more. You can schedule an initial appointment on our website, or you can just start by downloading our free guide about five ways to improve gut health and end food intolerances for good.
Why Resistant Starch Is Good For You
So today's topic is all about resistant starch and why it's good for you and your gut. But before we jump into the good stuff, let's tackle the basics first.
What exactly is resistant starch anyway?
Resistant starch is a form of carbohydrate that is composed of long chains of glucose. The word resistant comes from the fact that it is resistant to digestion because most of it passes through the small intestines unchanged.
Once it reaches the colon, it can be fermented by specific strains of gut bacteria into beneficial short-chain fatty acids. So what are some foods that are high in resistant starch? Underripe bananas, cooked rice, corn, all types of legumes and beans, oats, pearl barley, millet, peas, plantains, potatoes once cooked and cooled, and yams. Now not all resistance starch is created equal.
Did you know that there are actually four different types of resistance starch?
Let's break them down.
Type one is the type that's found in grains, legumes, and seeds, and this type resists digestion because it's physically protected and locked inside those fibrous cell walls. If those foods are milled or chewed, then the resistant starch content decreases.
Type number two is found in potatoes, plantains, some legumes, and unripe bananas when in their raw form. So once cooked, the starches become more digestible.
Type number three is the type that is formed when foods that are high in resistant starch such as potatoes, corn, and rice are cooked and then cooled. This cooling action turns some of the digestible starches into resistant starches via a process called retrogradation. Making sure to only lightly reheat these foods when you're ready to eat them to less than 130 degrees keeps this type three resistant starch intact.
Type number four is a synthetic form that's made in a lab.
Okay, now that we understand what resistance starch is, we've come to the fun part, how it can actually benefit our health. You likely have already heard that resistant starch benefits our gut health, but there are some other associations that you might not be aware of, so let's break each of them down.
Resistant Starch Is Good For You because...
Number one is that resistance starch feeds our microbiome. While most of the food we eat feeds and nourishes our cells and bodies, resistance starch feeds our microbiome. Our microbiome or our gut garden, as I like to call it, consists of a wide variety of different beneficial bacteria that live within our intestines.
They all play a huge role in not only just our gut health but our overall health as well. Resistant starch is a microbiota-accessible carbohydrate, which means they are a type of carbohydrate that our microbiome loves to ferment and it helps keep their colonies strong.
Something interesting to note, however, is that only certain types of bacteria can benefit from resistant starch, Ruminococcus bromii and bifidobacterium adolescentis are the two main strains that we've identified as being key players in the resistant starch breakdown.
Once this large glucose molecule of resistant starch is broken up, that's where benefit number two takes over.
Number two is increased short-chain fatty acid production. So once that large resistant starch molecule is broken down into smaller pieces, then other types of bacteria in our colons start to take over by continuing to break down these molecules ultimately resulting in short-chain fatty acids.
Short-chain fatty acids include acetate, propionate, and butyrate, and these compounds provide 70% of the energy for the cells that line our large intestine. On top of this, studies have shown that short-chain fatty acids inhibit the release of proinflammatory cytokines in our gut.
So having more short-chain fatty acids around is definitely a plus. Lastly, short-chain fatty acids help improve colonic motility blood flow, and balance the pH of our GI tract. All great things.
Number three is the increased absorption of minerals. This benefit is super neat and something we're just learning more and more about. Most of the studies evaluating this topic are animal studies, but they are finding that type three resistant starch when given to mice results in increased intestinal absorption of calcium, magnesium, and iron.
So if you feel like your absorption could use a little boost, some resistance starch might be a helpful addition to your diet.
Number four is improved insulin sensitivity and blood glucose control. That's right. Many studies have now shown a clear association between the two, and it's very exciting.
A 2015 single-blind crossover study had participants try three different resistant starch loads. The control was cooked white rice, which had the lowest resistant starch content. The first test rice was cooked and then cooled with a moderate resistant starch content, and then the second test rice was cooked, cooled, and then gently reheated with the highest resistant starch content.
What they found is that the second test, rice, the one with the highest resistant starch content, resulted in the most dramatic lowering of blood glucose levels compared to the initial control rice. So if you're trying to be mindful of your blood sugar levels, focusing on high-resistant starch foods might be a great step to implement.
The next time you make rice, give it some time to cool down before you eat it, and as long as you only reheat it very gently, the next day you'll get even more resistant starch.
Number five is reduced cholesterol levels. The cholesterol-lowering effect of resistant starch is still not fully understood, but the association is definitely there. A 2018 meta-analysis took an in-depth look at the results of 14 different trials on this topic.
What they found is that there is a consistent reduction in total cholesterol and LDL cholesterol when participants were given resistant starch and the effect was even greater when consumption was extended beyond four weeks.
Lastly, a higher dose so greater than 20 grams resulted in a reduction in triglyceride levels. Therefore, it seems like consistency is key just like most everything else, continually including moderate doses of resistant starch in the diet appears to have a beneficial impact on the lipid panel.
Number six is improved satiety. This is a commonly stated benefit of resistant starch, however, the research is a bit inconclusive. A 2022 double-blind randomized study dug into this further by giving half of their participants a standard wheat roll, and the other half that same wheat roll that was supplemented with type two resistance starch.
Lab markers of satiety improved. However, the subjective report of the participant's actual feelings of hunger and fullness didn't change. So while resistance search might have a slight effect on satiety based on lab work, the real-life effect is not that great.
Hopefully, more research will come out on this soon so that we can continue to learn more about resistance search's role in satiety.
So what's the best way to get more resistant starch into your diet?
As I mentioned in the beginning, there are four different types of resistant starch and each one plays a slightly different role in humans.
Type one and type three resistant starches are your best bet for a balance between optimal benefits and the least amount of risks. To review, type one includes things like whole seeds, legumes, and grains, and type three includes cooked and cooled starchy items like potatoes, corn, and rice.
There are type three resistant starch supplements out there, but my favorite option is getting it from Whole Foods as much as possible.
Type two resistant starch is a bit more controversial. This one includes raw potatoes, raw plantains, you know, raw legumes, and unripe bananas. You probably have some hesitancy already just thinking about this list.
Raw potatoes, a completely green banana, they can be hard on your gut to digest these in their raw form, plus they just aren't that appetizing either. Instead, I'd focus on a cooked potato or rice and allow it to cool before eating.
Type four, which is that synthetic form is not something that's found in nature, so I tend to leave those items on the shelf. Stick with your whole food sources of resistant starch as much as possible. Are you having trouble tolerating resistance starch?
As we chatted about earlier, resistant starch is indigestible, meaning it goes through our small intestine, unchanged to them be fermented by our microbiome and the large intestine. So if your gut is imbalanced or if you have gut inflammation, then there's a good chance that resistant starch isn't going to be handled properly as it passes through.
So this can lead to feelings of bloating, abdominal pain, gas, constipation, and diarrhea. So if you're experiencing gut issues, don't hesitate to reach out to us at Oswald Digestive Clinic. We are experts in gut health and would love to help you sort it all out. You can check out our clinic.
I hope this information about resistant starch was helpful to you and you're now feeling excited about incorporating more sources of type one and type three resistant starch in your diet. If you'd like to explore any of this information further or obtain an individualized nutrition plan, you can schedule an initial appointment at our clinic.
We also take insurance and some of our clients get full coverage, which is great, or you can start by just downloading our free guide. Thanks for watching and I hope you have a great rest of your day.
If you'd like to explore any of this information further or obtain an individualized nutrition plan, you can schedule an initial appointment at our clinic. We also take insurance and some of our clients get full coverage, which is great.
Or you can just start by downloading our FREE GUIDE: 5 WAYS TO IMPROVE GUT HEALTH