I’ve received some version of the following question on several occasions in the past few months and the consumption of resistant starch is often encouraged by Paleo professionals, so thought it was time to tackle this topic.
“Cynthia, what about resistant starch? I’ve heard it can be helpful for Candida overgrowth.”
If you’ve been with me a while, then you know I do not support the consumption of very much starch. Starch feeds Candida yeast and other microbes, contributes greatly to sugar and carb addiction, compulsive overeating, depression, anxiety, autonomic nervous system dysfunction, low blood sugar problems, obesity, and unwanted weight gain, and it’s hard on the adrenal glands, not to mention insulin resistance, type 2 diabetes, heart disease, dementia, cancer, and more.
However, there are two types of starch – digestible and resistant. Digestible starch is what causes a rise in blood sugar and the inevitable insulin response and a spike in neurotransmitters that is responsible for all the negative health effects listed above. Resistant starch, on the other hand, is a type of carbohydrate that cannot be broken down into glucose. Therefore, it resists digestion in the small intestine and travels on into the large intestine, where it becomes a food source for the bacteria that reside there. Thus, the purpose of consuming resistant starch is to feed and cross-feed the healthy flora that lives in your colon, so that they will multiply in numbers.
As you likely know, the healthy microbes in your gastrointestinal tract play a vital role in many functions within the human body including helping you digest food and absorb nutrients; produce a variety of nutrients like vitamin K, biotin, and folate; enhance immunity; protect us from pathogens; degrade toxins; produce short-chain fatty acids that we can burn for energy; recycle bile acids, water, and electrolytes; improve peristalsis and transit time, and support brain health. Therefore, encouraging a healthy population of friendly microbes is important for optimizing health.
Proponents of resistant starch report a wide variety of health benefits like deeper sleep with more vivid dreams, less body fat, improved insulin sensitivity, and blood sugar control, lower blood cholesterol and triglyceride levels, better digestion and bowel movements, higher energy, enhanced mood and feelings of well being, a higher level of satiation with meals and more.
So, on the surface, it seems that consuming a lot of resistant starch could be nothing but good, right? Well, not necessarily so.
Your gut biome (the community of commensal, symbiotic, and pathogenic microorganisms that share space within your gut), is incredibly complex and the flora that resides there varies greatly from individual to individual. Not only do friendly microbes occupy the area, but so do unhealthy and pathogenic ones. Some people have more pathogenic microbes than others. And, if there are a lot of unfriendly microbes present or if certain microbes are living in the small intestine that doesn’t belong there, or a particular microbe is present in too many numbers, they will feed on the resistant starch as well, which can lead to a whole host of problems. Even the good guys become pathogenic when they are out of balance.
If you visit various online forums that discuss the topic of increasing resistant starch in the diet, you will see there is a very wide variety of responses. Some people are reporting miraculous improvements, while others are reporting significant side effects, setbacks, and a decline in health (including diarrhea, abdominal pain, distention, gas, constipation, nausea, bloating, cramps, acid reflux, fatigue, brain fog, anxiety, psychological disturbances, and intestinal blockage.) The response one has is dependent on what microbes they have in their gut biome and where they are located.
Norm Robillard, PhD., microbiologist, and author of Fast Tract Digestion, helps shed some light on why this would be so. Robillard explains, if an individual has many of the microbes that typically live in the colon present in the small intestine where they don’t belong, as is the case in SIBO and other related conditions like IBS, and GERD, then the organisms in the small intestine will feed on the resistant starch as well, thus aggravating the symptoms of SIBO, IBS, GERD, etc. Furthermore, according to research by Robillard, people with IBS (which can be a SIBO related condition) tend to have an overabundance of a particular bacteria called firmicutes and an overall decrease in microbial diversity. Firmicutes feed primarily on carbs, sugar, fiber, and starches.
In a healthy gut, there should be a wide variety of bacterial species competing for space and nutrients. In an unhealthy gut, there will be less diversity and one particular bacteria may become dominant. Robillard explains, that If a particular type of bacteria that feeds on resistant starch, like the firmicute population, is out of proportion; then an increase in symptoms may occur. Therefore, people with IBS, SIBO, acid reflux, and autoimmune conditions like multiple sclerosis, Lupus, rheumatoid arthritis, Grave’s and Hashimoto’s thyroiditis, psoriasis, inflammatory bowel disease (Crohn’s, ulcerative colitis), and celiac disease, as well as allergies and asthma, all of which are related to microbial overgrowth or imbalances, are likely to have an increase in symptoms in response to too much resistant starch.
Robillard cites a variety of studies that indicate a diet rich in complex polysaccharides leads to an increase in firmicutes, actinobacteria, and certain clostridia, but less bacteroidetes and other species of clostridia, which results in less diversity – the same circumstances that are found to be associated with IBS.
He explains that limiting the food source for the “polysaccharide loving microbes,” puts them on a diet. Eating a diet that is rich in animal-based foods combined with a limited amount of fermentable carbs promotes an environment where species of bacteria that metabolize amino acids and other animal-based macronutrients and the firmicutes and clostridia that prefer carbs can compete, without allowing one or the other to become dominant.
Robillard states that resistant starch is just like any other indigestible carb that be can be fermented by our microbes, which means it can exacerbate SIBO, cause infection with pathogens, excess toxin, and gas production, and an increase in “microbe-mediated formation of carcinogenic compounds.” “A lean diet for our gut microbes fosters healthy competition in the gut that will favor the survival of well adapted organisms best suited to be our partners in digestion and health.” Please read Norm’s excellent information on this topic, here and here, if you would like to learn more. My personal experience with resistant starch, which I share in more detail further down the page, completely supports the findings of Robillard.
Dr. Grace Liu, a medical pharmacist, with a great deal of knowledge on this topic, also cautions that anyone with IBS, SIBO, an autoimmune condition or who is precancerous or cancerous for colorectal cancer should avoid resistant starch for the same reasons – rogue bacteria, pathogens, and/or microbes inhabiting places they shouldn’t. She also cites research that suggests that people with IBS have too many short-chain fatty acids, which can lead to symptoms like depression, anxiety, and migraines. Therefore, increasing fermentable and indigestible carbs like resistant starch will increase short-chain fatty acids even more. You should visit Grace’s site as well.
Additionally, Dr. Allison Siebecker ND, Medical Director of the SIBO Center for Digestive Health at NCNM Clinic in Portland OR, lists resistant starch as one of the food sources for the bacteria that fuel SIBO.
So, to come back to the original question in my opening paragraph in regard to whether resistant starch can be helpful for people with Candida, I would say the following. Although in theory, it seems that consuming something that would increase the healthy flora in the gut should be helpful for individuals with Candida, in reality, that may not be the case. Since the cause of Candida is gut dysbiosis, which means they may have high levels of rogue and pathogenic bacteria; and many individuals with Candida have IBS or SIBO or an autoimmune condition in addition to yeast overgrowth, that means people with Candida most likely fall under the category of those who would have a worsening of symptoms in response to resistant starch. However, that wouldn’t be one hundred percent true across the board. It would depend on many factors like age, how severe the yeast overgrowth is and long they’ve had it, other conditions that are present, and primarily the gut biome of each individual.
I have read accounts of people with Candida who felt that resistant starch was beneficial, but it is my opinion that they would be the exception and not the rule. If you have a simple, clear-cut case of Candida, (and Candida only,) then benefits may be possible. Resistant starch should not feed Candida since it can’t be converted into glucose. However, few people will fit these criteria, because Candida is rarely simple or occurs alone. Although resistant starch may increase bacteria that will deter Candida, it will also increase the bacteria that will fuel SIBO, IBS, GERD, and autoimmunity, if they are present, thus causing an exacerbation of symptoms. I would encourage anyone with Candida to exercise extreme caution if they want to experiment with resistant starch. As I will share further below, the side effects can be very disruptive and produce a significant setback in health that is not easily reversed. If you have SIBO, IBS, or GERD, I wouldn’t even consider it. It’s also critical to note that you may not be aware that you have SIBO because many of its symptoms overlap with Candida and other conditions and it is often overlooked. You can visit the SIBO area of the blog to learn more and help you assess.
If you do want to explore this arena, then here are a few things to be aware of before you begin.
There are four different types of resistant starch known as:
RS1 – found in seeds, legumes, and unprocessed whole grains and is resistant because they are coated with a protective matrix.
RS2– occurs naturally in some foods like uncooked potatoes, green bananas, and plantains.
RS3 – forms when foods that contain starch are cooked and then cooled like potatoes, legumes, sushi rice. Cooking and cooling the food causes the starch to become less soluble.
RS4 – man-made starches produced by chemically modifying the starch.
Now, since legumes and grains contain a variety of antinutrients and are not healthy for us, we don’t even consider them. And of course, we don’t want to consume the man-made chemical versions either. So, in the Paleo world, people using resistant starch are focused on foods in the RS2 and RS3 category, primarily uncooked potato starch, green bananas or flour, and plantain flour or cooking and cooling potatoes (although potatoes are not truly Paleo). It can be found in lesser amounts in a variety of other starchy foods like yams, sweet potatoes, squash, tubers, roots, and nuts.
The most popular method being used to acquire resistant starch is to supplement the diet with 2 to 4 TBSPS of Bob’s Red Mill unmodified potato starch or green banana or plantain flour. If you choose the potato flour, be sure that it is unmodified. Potatoes eaten raw are poisonous and the starch in Bob’s Red Mill has been processed in a manner that removes the toxins. Additionally, you don’t want potato flour, it must be pure potato starch.
However, according to Dr. Grace Liu, “whole food resistant starch trumps potato starch” for effectiveness so there should be a combination of whole foods with the potato starch, banana flour, plantain flour, etc. According to Liu, this will feed the whole village of microbes, not just the ones that eat RS2, and thus will promote more microbial diversity and prevent overfeeding one particular species.
Herein lies another problem for people with Candida. Any of the foods that are high in resistant starch are also high in digestible starch, which will feed Candida and spike blood sugar and insulin and overstimulate neurotransmitters in the brain, resulting in cravings for sugar and carbs if too many are eaten.
Additionally, most people with Candida have an addiction to sugar and carbs, which means they have metabolic damage. People with metabolic damage do not handle foods that are high in glucose (starch) very well, and consumption of them leads to cravings and binging on sugar and carbs, which will then feed Candida.
If you stick with the raw starch from potatoes, banana flour, or plantain flour, you will not be consuming very much digestible starch, because they are mostly resistant. However, if you add in the starchy foods like cooked and cooled potatoes, yams, sweet potatoes, squash, etc., then they are quite high in digestible carbs. In order to address Candida overgrowth and prevent cravings for sugar and carbs, total carbohydrate levels (including the foods high in resistant starch) must be kept minimized. In most cases, the total carbohydrate level should be kept below 50 mg per day. So be sure to take this into account.
My Resistant Starch Experiment
I had read about all the great things that should happen when you consume resistant starch from a couple of sources that I trust and I had clients asking my opinion on the topic, so I decided to give it a try, as I like to have first-hand experience on an approach before advising one to engage or abstain.
I’ve had a lifelong issue with Candida and IBS and more recently with H pylori, all of which I keep managed with a very strict low-carb, low-starch, low FODMAPs, Paleo diet, and a variety of other strategies, that can be found in my Candida Secrets book or my Break Your Sugar Addiction Today Toolkit if you’re interested. I had suspected I may have a mild SIBO problem, but I wasn’t completely sure until I did this experiment.
I started out with a teaspoon of potato starch and nothing happened so I slowly increased. When I got up to the recommended 4 TBSPS a day I developed severe acid reflux, indigestion, heartburn, pain in my stomach and small intestine, and severe foul-smelling gas and stool. So I immediately discontinued for two days. After two days I felt better, so I decided to take a lower dose of 2 TBSPS a day. For about four days or so I didn’t notice much of anything except a mild increase in gas, and then all of sudden, wham, I was hit with the following: (and please do note, that I had none of these symptoms prior to taking resistant starch)
- extremely excessive gas
- foul smelling gas and stool (smelled like sulfur)
- disturbed sleep
- an increase in migraines
- severe inflammation, swelling, burning, and pain in the small intestine
- severe acid reflux, indigestion, and heart burn (it would wake me up in the middle of the night with intense belching)
- achy sore spots all over my body
- greatly stressed my adrenals
- pain and burning in my right kidney and bladder
- gallbladder inflammation
- mild depression and loss of feelings of well-being and other weird brain symptoms
- unexplained fear
- brain fog
Symptoms continued to snowball for several days after I stopped the resistant starch. The pain, burning, inflammation, etc. then traveled to the large intestine. There was so much swelling that I looked like I was six months pregnant. The pain in my colon then radiated into my right shoulder blade and spine and it was difficult to move.
At this point, I was freaking out, because I knew I had fed something I shouldn’t have fed and it was continuing to spread like a wildfire even though I cut off its food source. So I started drinking food-grade hydrogen peroxide to kill some of them off and this was helpful; things began to improve right away, but slowly. However, as of today, January 2, 2015, it’s been more than two weeks since I discontinued the resistant starch and I am still not completely back to normal. I get severe GI distress if eat more than 30 grams of carbs per day and even that is not providing complete relief.
I then began searching the Internet to find out what the heck happened to me and that is when I discovered the information from Norm Robillard, PhD., Dr. Grace Liu, and Dr. Allison Siebeckeer, that I presented to you above. I pulled out my GI Effects Comprehensive Stool Test that I had a few months back and looked at my bacteria levels, and sure enough, my results reflected exactly what Norm said would produce negative effects: I had high levels of firmicutes and not very much diversity.
At another time prior to this experiment I had tried using cooled and cooked potatoes, but with only one meal I had intense diarrhea, cramping, pain, burning and inflammation in my small intestine, disturbed sleep, acid reflux, and more, so I discontinued immediately and didn’t consider trying again. I typically don’t eat potatoes very often, because they will trigger sugar addiction and feed Candida, but I did so for this experiment. So I wasn’t sure if it was the resistant starch or the fermentable carbs that were the problem and thus why I tried the pure potato starch.
So in a nutshell, I can sum this up by saying that resistant starch resulted in a very significant setback in my health. I have never experienced such severe GI distress in my life. However, the good thing to come out of this situation is that I have learned something very valuable about my gut biome and now I know where I need to direct my efforts for making more improvements. Prior to this experiment, I had attributed all my upper GI symptoms to H. pylori, but what I discovered here is that SIBO is causing a great deal of these symptoms.
I have arrived at the same conclusion as Robillard, and couldn’t say it any better than he has, with the following statement:
“Clearly there is evidence that we, and our resident microbes, derive benefit from some level of resistant starch and/or other indigestible fibers in our diet. Whether or not we need to supplement our diet beyond what we receive from simply eating some fiber-rich green leafy vegetables, avocados, nuts, and some fruit… is an open question. “
Update February 2015
I wanted to provide an update on my situation that has stemmed from my experiment mentioned above. As of the end of February 2015, it has been almost three months, and I continue to have severe GI distress that was created by the resistant starch. I have completely lost my ability to consume any fruit or nuts and must continue to keep my carb intake at 30 grams per day. If I go above the 30 grams per day, then most of the symptoms I listed above return. Prior to the consumption of resistant starch, I could eat a half cup of fruit and two tablespoons of nut butter three times a week with very few symptoms and had no pain with protein or fat.
However, now, I do not even get complete relief by staying at the 30 grams either. Symptoms are significantly better, but I still have quite a bit of belching from the protein and fat. I have less gas staying off the carbs, but I still have more than usual. If I eat carbs, then the gas smells like sulfur, but when I eat protein and fat, it smells like ammonia, which indicates my bacteria are eating my protein and fat. I have severe abdominal pain all the time. i believe I’ve had several bouts of pancreatitis, but I didn’t have it confirmed by a doctor. My pancreas, duodenum, gallbladder, and bile duct hurt consistently.
I am currently taking some herbal antibiotics to kill the bacteria and reduce inflammation, and this is providing quite a bit of relief, but not complete. After starting the herbals, most of the pain in my pancreas stopped, but it moved down towards the cecum area. It appears the bacteria relocated to that area and the herbs are not as effective for killing them down there. I’m going to give it a little bit longer to see if it improves more, but I think I may be forced to take a pharmaceutical-based antibiotic if the pain does not let up soon.
Clearly, the resistant starch increased the bacteria in my small intestine to an outrageous level, and once that happens, it is not easy to reduce the population.
I share this with you because I want others to know how serious the side effects and aftermath can be from resistant starch if you have SIBO. I would have never done this had known what I know now. This is truly the worse thing I have ever done for myself. I just never imagined that the consequences could be so severe or that they would be so difficult to turn around. I assumed the worse that could happen was an increase in symptoms that would resolve once I stopped consumption, but that was not the case. So, once again, I urge you to exercise extreme caution with resistant starch.
(Update – March 2015. The herbals were not strong enough and I had to take a prescription-based antibiotic. This helped immensely, but I continue to use herbals periodically and be very strict on my diet or things flare up again.)