Marks Daily Apple
Serving up health and fitness insights (daily, of course) with a side of irreverence.
2 Apr

Resistant Starch: Your Questions Answered

PotatoesLast week’s Definitive Guide to Resistant Starch garnered a lot of attention. While the article covered a lot of ground, many of you had lingering questions and concerns about the topic: What is and isn’t resistant starch? How much resistant starch should I be eating? Why is resistant starch good for me? What is resistant starch again?

I don’t blame you; it’s a confusing one that appears, on first glance, to challenge some of the fundamental Primal ideas about food and nutrition.

Today, I’m going to answer as many questions from last week as I can. Hopefully it clears up most of the bigger questions.

Let’s get right to it:

Do the benefits of RS outweigh the negatives of rice, legumes, potatoes, etc.?

Great question.

Rice and potatoes, yes. I’ve already spoken on both those subjects in previous posts, and my basic conclusion is that both rice and potatoes are relatively toxin-free sources of starch that an insulin-sensitive, sufficiently-active individual can likely consume in moderation without ill effect. For both foods, the negative effects come from the carb load they represent, which is simply too high for some people. But by cooking and cooling them, you reduce the carb load, reduce the glucose response, and improve your insulin sensitivity. In essence, any “negatives” are mitigated by the emphasis on resistant starch. If you have trouble with glucose tolerance, and you’re looking to drop weight, you should still exercise caution with these foods and heed the Carb Curve, but preparing them in a way that increases the RS content will only make them less problematic.

One note: potatoes are iffy for people with nightshade intolerance. So there’s that to consider.

Legumes, I’m not sure. I strongly suspect that the health benefits ascribed to legumes are solely due to the prebiotic, RS effects, which interest me but are not the sole province of the legume. But the fact remains that many people simply don’t tolerate legumes very well. It could be that some of the tolerance issues stem from disrupted gut flora and introducing RS will ameliorate your troubles, but who knows? We’re still learning a lot. In the meantime, I’m not too interested in soaking beans. There’s nothing essential about them, so long as we’re getting RS from other sources.

I’m a little confused…how does one go about adding RS in whole food form without doubling or tripling their normal daily carb intake? I can’t see eating 1-2 green bananas and a couple raw potatoes each day, in addition to normal amounts of carbs from veggies and fruit (I usually have one serving of fruit a day– berries, if possible) and still staying under 100-150 carbs. Please, enlighten me!

Believe it or not, you can easily eat green bananas without tripling your digestible carb intake. And that’s the key: you don’t digest these carbs, your gut flora do. An average large banana contains a hair over 30 grams of carbohydrate. If it’s green and totally unripe, the majority of that carbohydrate will be resistant starch that your body does not digest into glucose.

You’ll know you’re getting the good stuff when the banana is crispy and leaves a chalky aftertaste in your mouth. Pleasant, I know. But added to a smoothie, it’s actually quite nice. In fact, here’s a recipe I’ve been playing around with:

  • Cup of milk (coconut, almond, cow, goat, etc)
  • Large green banana, peeled and sliced
  • Quarter teaspoon of vanilla extract
  • Quarter teaspoon of cinnamon
  • Half teaspoon of honey (may be unnecessary depending on the sweetness of your bananas)

I assume that the time of day you take RS does not matter?

It shouldn’t. Once you’ve established a healthy population of butyrate-producing gut bugs, they don’t need to be fed at a certain time every day. They’re quite malleable and adaptive, and they’ll also begin feeding on other fermentable fibers in your foods.

What is the reason to supplement RS instead of getting it from food? How much RS is “good enough” and how much real food would meet that amount?

Supplemental RS is just easier, and most of the research in support of it has used supplemental RS-rich powders – so we know it works. But real food probably works even better since it comes with vitamins, minerals, and polyphenols (which have prebiotic effects in their own right), and it most closely resembles the way our early ancestors consumed RS.

Let’s see. If you can work your way up to between 30 and 40 grams of RS, whether from food or from powders, you’ll be in a good place. That’s the dose used in much of the research, and it’s where butyrate production is maximized.

What does that look like in food form?

600 grams of baked, then cooled, potato has around 25 grams. You can even lightly heat the potato after it’s been cooled and retain the RS.

1 large (8 inch) green, fully unripe banana has somewhere between 20-25 grams. A large green plantain has about 50 grams. Not the most palatable, but it’s doable, especially if you slice into discs and dehydrate into chips. A smoothie masks it well, too.

Any idea if heating the potato starch (like using it as a thickening agent in soups/stews) negates its RS function?

Yes, the RS will be completely negated. Sorry. It does make a good thickener, though.

Cooked and cooled rice – as in sushi? Or does the vinegar somehow negate the benefit of the resistant starch?

Yes, cold sushi rice will contain RS. Good sushi restaurants generally keep their rice at room temperature, though, so I’m not sure you’ll get the retrograde RS effect unless you go for grocery store deli case sushi. And hey, I actually like that stuff, so there’s no shame in eating it. Just avoid gas station sushi if you know what’s good for you.

Vinegar shouldn’t affect it either way. Vinegar does reduce the blood glucose response when consumed with carb-rich foods, so it might be a nice supplement in its own right if that’s an effect you’re after.

So that pizza crust recipe has mostly tapioca starch/flour (same) in it. (Also, not Potato Starch–potato flour) If I make the crusts and freeze them and then reheat and eat, would the RS still be usable? Same as the potatoes and rice I would think. So perhaps that is a go on the RS.

I don’t think it works like that. For retrograde RS to form, it has to be in its whole form – potatoes, not potato starch; cassava, not tapioca starch; rice, not rice flour.

Question about “cooked and cooled” – what the heck does that mean? So, I cook it, and cool it. Does that mean I have to eat it cold to get the resistant starch? If I zap my bowl of bean soup and rice that came out of the fridge, when does it lose the resistance to digestion?

Retrograded RS (cooked and cooled) is maintained during subsequent heating. You can even heat it and cool it once again to create even more RS. So you don’t have to eat it cold, though I would advise against re-heating a cooked and cooled RS source into oblivion. Keep the heat relatively low.

Should the carbohydrates from resistant starches (for example, a cooked and cooled potato) still be counted in daily consumption if it is not digested?

Some of it should still be counted, because not all – or even most – of the starch is resistant. Most of it is good old digestible glucose. But you can subtract the 4-5 grams of RS from the 21 grams total starch in every 100 grams of cooked and cooled potato. Not bad, eh?

And remember, it’s not that the 4-5 grams become inert, useless matter passing through your body. They are bioactive, just not with the biology of the host. They turn into fatty acids that fuel your colon and improve your ability to tolerate the digestible glucose you consumed along with them.

Is just eating Pistachio’s (or other seeds) enough RS to do the trick?

Probably not. To hit the 30-40 grams of resistant starch that maximizes benefits in most trials with pistachios would require a lot – of money, of calories, of shelling. 100 grams of roasted pistachios has around 3.5 grams of RS. That may be in the shell, and raw pistachios may have more, but either way it’s not a huge amount. Not bad, not great. The beauty of the less calorically dense RS sources is that they allow a more varied diet. It’s nothing to add a couple tablespoons of potato starch to your diet.

That said, pistachios are potent prebiotics. One recent study found that they increased butyrate-producing bacteria in the colon, outperforming almonds. You should definitely eat pistachios, but I think you should also eat other more concentrated sources of RS.

That’s the beauty of it all: it’s not a competition! We can eat pistachios and other things at the same time without disrupting the effectiveness of either.

Question: would hummus fit the bill as cooked & cooled legumes?

Yes, hummus seems to qualify even though it’s not Primal. According to the PDF from last week’s post, 100 grams of hummus has 4.1 grams of RS. Hummus made from soaked chickpeas will have more than hummus made from canned chickpeas, however.

What would be the best way to gradually incorporate RS into the diet for a person that has gut inflammation with chronic bloating?

You need probiotics. And in your case, I doubt yogurt or even kefir will be sufficient. Try something soil-based, as in the same types of probiotic organisms that Grok was getting on a regular basis simply from living. These are likely the microbes to which our guts are evolutionarily accustomed.

Primal Flora works (worked for me with RS!); it provides a high dose of two specific soil-based strains that have been shown to be helpful in clinical trials. You could also go more broad-spectrum, with more soil-based strains but lower concentrations.

Start really, really, really small with the RS. If you’re going with the unmodified potato starch, start with 1/4 to 1/2 a teaspoon. It will look like almost nothing. Increase it by 1/4 tsp slowly as comfort allows.

If that doesn’t work – but I imagine it would – and your gut is really compromised, I suggest trying Dr. BG’s gut healing protocol. It involves probiotics, prebiotics, and a number of other, more drastic but potentially necessary steps. The good doc is a bit wild, but in a good way. Just read her stuff at least twice and you’ll figure it out. Reading it out loud seems to help, too. She certainly has a way with language!

Does this mean I can start eating sushi and potato salad??! 😉

Well, you can choose to eat anything you want, of course. That’s never changed. What this does indicate is that those foods, when cooled, have unique effects, different than if you were to eat a bowl of hot steamed rice or a large baked potato fresh from the oven.

The preponderance of evidence suggests that the potato salad and the cold sushi rice will result in a lower blood glucose response and feed the helpful critters in your gut – both good things. But before you go digging into that store bought potato salad on a regular basis, consider avoiding the seed oils and making your own. I’m a fan of lemon juice, olive oil, salt, and fresh herbs, myself. I can rarely be bothered to make my own mayo, although that’s also a good option.

Anyone have a recipe using raw potato starch that can be easily incorporated into a primal/paleo diet (meat, eggs, veges, occasional fruit)? I don’t do smoothies, nor do I do fruit juice or yogurt.

Aside from smoothies, sparkling water is the best vehicle I’ve found for potato starch. The bubbles seem to enhance the dispersal of potato starch granules into the medium, even without a blender. Just a fork or even a quick stir with your index finger is enough to get it completely mixed in.

So what to use? Bob’s Red Mill Potato Starch or Bob’s Red Mill Tapioca Flour?

Potato starch seems to be the most reliable way. From reading the comment sections on blogs and posts on various forums, the digestibility of tapioca starch/flour varies from person to person. Many people seem to get elevated blood sugar after taking a tablespoon or two of the tapioca, whereas potato starch is almost invariably indigestible.

Can the potatoes be fried in lard and then cooled? I would rather try a yummy food source then a powder.

A few weeks back, I described my method for foolproof, easy crispy root vegetables. You pre-bake them and store in the fridge. This increases the RS content of the potato. When you’re ready to fry them, simply peel the skin, cut them up into the desired shape (cube, fry, etc), and lightly pan fry them in the fat of your choice. Lard is a great option. Since they’re already cooked, you don’t need a lot of heat or a lengthy cooking time, and the RS is preserved.

If we’re taking probiotics without RS as well – what is happening? The bacteria in the probiotics are starving? But don’t they eat other stuff besides RS? Sorry, I know I sound like a boob, but – I’m still a little confused.

No, the probiotics can still help, by partial colonization. But for the best results, you’ll want to provide food so that the probiotics have more lasting power and can hitch a ride into the colon where they do the most good. Feed the animals; they aren’t bears and it’s not Yellowstone! It can be resistant starch and/or any other prebiotic fiber. The point is to feed them stuff they can eat, thrive on, and ride on.

RS fits the bill.

One more question – how does this need for RS fit into the Grok-lore? What did our Paleo ancestors do that we aren’t doing?

As I’ve written before, wild tubers, roots, and other underground storage organs are frequently highly fibrous with lots of indigestible starch. That’s what Grok would have encountered, not the smooth, starchy goodness of a Russet potato, which had to be selected for by the experienced hands of agrarian tuber breeders.

We can’t all eat dirt-encrusted cattails rich in resistant starch, but we can approximate the effects with modern tools. Taking soil-based probiotics and emphasizing preparation methods that maximize resistant starch content is, by all accounts, an extremely Primal and biologically-appropriate way to emulate one important aspect of our evolutionary metabolic environment.

Any thoughts on the resistant starch found in Quest Bars? Quest Bars contain isomalto-oligosaccharides. The makers claim this is a resistant starch.

It’s not a resistant starch per se, but rather a prebiotic fermentable fiber. Studies indicate that while its consumption does improve constipation and increase production of the short chain fatty acids (SCFAs) propionate and acetate, it does not increase production of the most beneficial SCFA, butyrate.

Is consuming RS the only way to feed our gut?

No, definitely not. Other prebiotic substances matter, like various plant fibers (inulin, pectin), dark chocolate, and even connective tissue (yes, animal fiber – the crunchy gristle and cartilage too many people discard). With a Primal eating plan rich in plants and whole animals (including bones and broth), you should be getting plenty. But resistant starch is an important, unique prebiotic that makes feeding our gut a whole lot easier and more effective.

That’s it for today, folks. Thanks for reading!

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You want comments? We got comments:

Imagine you’re George Clooney. Take a moment to admire your grooming and wit. Okay, now imagine someone walks up to you and asks, “What’s your name?” You say, “I’m George Clooney.” Or maybe you say, “I’m the Clooninator!” You don’t say “I’m George of George Clooney Sells Movies Blog” and you certainly don’t say, “I’m Clooney Weight Loss Plan”. So while spam is technically meat, it ain’t anywhere near Primal. Please nickname yourself something your friends would call you.

  1. Several comments on this post by Richard Nikoley of freetheanimal address the nightshade question. One commenter who is very sensitive to nightshades has had no trouble at all with potato starch. Another commenter warned about possible risks with eating raw potatoes and said potato starch is much safer than eating raw potatoes.

    Here is a link — scroll down to see the comments on nightshades and raw potatoes.

    Wheatless Ellen wrote on April 2nd, 2014
  2. As far as food sources for RS go, what about Jerusalem Artichokes (aka-Sunchokes)? I cannot find anything one way or the other on this tuber.

    Terrell wrote on April 2nd, 2014
    • My understanding is that sunchokes are high in inulin, a good prebiotic, but not RS.

      Energy! wrote on May 25th, 2014
  3. I’ve been PS for five months. Lowered my fasting blood glucose by up to forty points, although it is back up a bit now.

    All these questions about eating this or that to get RS. You have to really work hard at that to get the 40 grams a day, and you will inevitably be bring along other, digestible carbs. Just buckle down and do the PS in water. It’s almost tasteless. There’s no need to hide it in that paleo blender smoothie.

    You can save a lot of money by buying PS at the Asian Market, literally a fraction of Bob’s at Whole Foods. Make sure you get starch, not flour. Starch will sink to the bottom of a cup of water and will not dissolve.

    Although most of the carbs in PS aren’t digested as carbs, they most surely have calories, if you are counting. The very first bag of Bob’s I got listed the calories as fats! I was amazed, then they changed it to conventional carbs. I use 30 calories per tablespoon as fats in my diet recording.

    OnTheBayou wrote on April 2nd, 2014
    • {wince} My first consideration would be — what is the quality standard that Chinese potato starch is prepared to? Any melamine in it? Heavy metals? Other contaminants (intentional or not)? You can pretty well rely on the idea that the US govt is NOT bothering to/able to/intending to actually inspect any of it to see if it is contaminated. I expect that our primal/paleo/N=1 small group (compared to the whole American population) isn’t causing an unmanageable pressure on the producers to ‘make more’ but, as with any (apparent) fad, people/companies may rush in to make money by making product without a commitment to wholesomeness and health!

      (I hate to write that, but there it is! If “the Chinese” — that is, *some* producers, mfgs, and govt inspectors in China — will poison dogs here (and OMG! several hundred infants there!) with melamine in food or formula; how do we protect ourselves?)

      Elenor wrote on April 3rd, 2014
      • Elenor, you are jumping to conclusions. The potato start I buy clearly says on the label, “Made in U.S.A.” I presume Bob’s Red Mill is, too, but I’ve never learned if it is.

        Life has enough things to justifiably be fearful of. Don’t go making up invalid ones.

        OnTheBayou wrote on April 3rd, 2014
        • Good to know your ‘Asian’ PS isn’t Asian.

          However: “Don’t go making up invalid ones.”

          Worrying about products made in China and not inspected on their way here for wholesomeness and health is not an invalid concern. (And, just as with stuff labeled “virgin olive oil” sometimes being partly or mostly canola oil — being “overly” careful may not be “overly” at all!)

          Elenor wrote on April 3rd, 2014
  4. Waaaaiitaminute. So let me get this straight.. I can now cook rice in my rice cooker, then put the rice in the fridge, then heat it in the microwave when I want to… And that qualifies as RS? This sounds too good to be true. Am I understanding this correctly? ?

    ricebaby69 wrote on April 2nd, 2014
  5. Our biome is the result of what we eat, not a preexisting colony of bacteria that needs to be fed and taken care of like a garden. A diet that is animal based and extremely limited in vegetable matter will never need resistance starch as it will never have provided an every source for the bacteria that thrive on resistance starch to colonize our colon.

    The bacteria is the result of what we eat, not the reason to choose what we eat.

    And from the time a million and a half ago that we began cooking our tubers with fire we have not been regularly eating raw tubers. And, again, until the advent of sustained agriculture, vegetables were a limited part of our diet.

    I am in the carnivore tent. If you eat meat, fish, eggs, shellfish, and raw fat dairy if you can, you will never need a vegetable or fruit, or need bacteria that aid in their digestion . You only need the bacteria that help you to digest what you eat. This is the point, you only need the bacteria that naturally develops from the foods that you eat.

    Michael wrote on April 2nd, 2014
    • Thank you, Michael. It is so hard to resist the “you MUST eat your veggies or DIE!” (and not from vegans but from our primal / paleo / LCHF brothers and sisters), that it becomes a steady drumbeat around food…

      In my family we joke that my older sister — the 40-yr-vegetarian — got all the veggie genes and I got all the meat genes! As infants, children, kids, and teens — our parents despaired because she HATED meat, and I HATED veg! Interestingly, SHE was usually released from table way sooner than I was — it was/is, apparently, more acceptable to refuse to eat your meat course than your veg course — well, that and she could slip it to the dog — who flat-out refused to eat my veg under the table! (The traitor-canine!)

      Elenor wrote on April 3rd, 2014
    • @Michael – “If you eat meat, fish, eggs, shellfish, and raw fat dairy if you can, you will never need a vegetable or fruit”

      And what your source of Vitamin C would be?

      GTR wrote on April 3rd, 2014
      • Organ meat of grass fed animals, wild game, and marine mammals

        To be clear, I will occasionally eat fresh, ripe fruit in season from the trees that how in my yard or local area. And I sometimes eat the fruit vegetables like cucumber or tomatoes, but rarely and only in season from local sources.

        It is very easy for me to go months without fruit and weeks without vegetables.

        Vegetable matter is definitely of minimal importance in my diet and my biome is perfectly developed for my diet. As for MCT oil, butter and goat and sheep milk provide more that adequate amounts, with sheep cheese such as manchego and feta high sources. The actual percentage of MCT oil to other oils for a healthy diet is very small.

        Michael wrote on April 4th, 2014
    • Thanks for one of the few voices of sanity here. I am disappointed that Mark jumped on the RS bandwagon.

      Sondra Rose wrote on April 3rd, 2014
      • My comment above was in reply to Michael.

        Sondra Rose wrote on April 3rd, 2014
      • Sondra I saw on your website you live in PT. I live in Olympia.

        Michael wrote on April 4th, 2014
        • Hey Michael!

          Lots of Primal peeps around here.

          Most of our raw vegan friends have succumbed to the lure of bone broth!


          Sondra Rose wrote on April 4th, 2014
    • @Michael:

      “Research comparing the gut microbiome of humans and other animals using 16S ribosomal RNA gene sequences provide some interesting insight into the diet our microbiome might be most accustomed, tuned our immune system, and kept our gut from leaking. When the gut microbiome of herbivores (e.g., sheep, cow, giraffe, gorilla, horse, rhinoceros), omnivores (e.g., ring-tailed lemurs, baboon, humans, chimpanzee, bonobo, spider monkey), and carnivores (e.g., polar bear, dog, hyena, lion) are compared, human samples not surprisingly cluster more closely with other omnivores. Interestingly, when compared to other hominids, humans cluster more closely with the bonobo diet. While bonobos do eat a small amount of leaves and meat, they are true frugivores, with a diet dominated by, as the name implies, fruit. Therefore, from the perspective of the microbiome, humans may be considered frugivores, although specialized, eating seeds and meat depending on availability. Flexibility is fundamental.
      Deeper shotgun prosequencing of the genes encoded by the trillions of bacteria in the gut across these same diverse mammals, reveal that the microbiome of carnivores are endowed with enzymes specialized to degrade proteins as an energy source, while the microbiomes of herbivores like sheep and gorillas are enriched with enzymes specialized to synthesize amino acid building blocks. Humans, in this case, are more like the gentle herbivores than the top-level carnivores we are often compared.”

      GTR wrote on April 4th, 2014
      • Interesting. I would need to break that information down to specific human populations with particular diets to have any use for me.

        Do populations eating a high amount of vegetable and fruit in their daily diet and that of their ancestors have the same biome composition as populations that eat primarily animals and rarely vegetables and have traditionally eaten this way for thousands of years? If a child is breast fed and then fed an animal based diet its entire life have a biome waiting patiently for the first piece of fruit?

        The critical point remains, the biome develops as a response to what we eat. And the evolutionary adaptions of bacteria is much faster that a human being. Biomes adapt quickly to changing human diets.

        A broad picture of what all humanity eats does not help an individual make a specific dietary decision regarding a particular food, especially something as unusual as eating raw tubers, unripened fruit, and potato starch.

        Choose the healthiest diet you can, pay careful attention to dietary effects, and your biome will adjust to meet your individual diet as it evolves. Do not make your dietary decisions based on some concept of keeping your colon bacteria happy.

        Michael wrote on April 4th, 2014
        • When it comes to the microbiome, yes children get it from their mothers. It differs between individual mothers/newborns, but it is still more specie-specific; eg one infant is closer to other human than let’s say to a lion newborn. If you don’t get antibiotics these initial bugs can stay there for a long time.

          (NPR: The Invisible Universe Of The Human Microbiome)

          If you eat a proper omnivorous diet, then your gut is dominated by bacteria from groups called Firmicutes and Bacterioides. Plant eaters tend to have both – but much more Firmicutes. Michael Pollan (“Eat food. Not too much. Mostly plants.”) has a gut with close to 60% Firmicutes inside, rest mostly bacterioides – with like few percent other. Omnivorous, but meat eating people can have like 60% bacterioides with like rest 35% firmicutes – but stil have both.

          When it comes to eating animals – they also have fiber-like substances in them, that are not digested, and pass to the gut to feed bacteria. These include parts like feathers, hair, but also collagen fibers. There’s a series on freetheanimal by Duck Dodgers about it. Notice these are extremaly rare in muscle meat – so if you only eat muscle meat you don’t get them.

          Your assertion that whatever you eat the microbiome adapts might be partially true – unfortunately we are only adapted to a few configurations. If you eat improperly, thus creating wrong configuration in your gut – it leads to a diesease.

          Examples of wrong configurations are here (Larry Smarr, Can we quantify our own ilness, look at about 9 minutes). Two diesease configuration are like: too much proteobacteria – ulcerative colitis, too few bacterioides – Crohns diesease.

          The advantage of RS-supplemented omnivorous diet it that it directs your gut into a safe configuration, thus avoiding dieseased ones.

          GTR wrote on April 6th, 2014
        • GTR, Thanks for all the information. At our regenerative medicine clinic we work with many people with differing manifestations of inflammatory response and all with some digestive issues. The more serious are those eating processed foods, vegans, and the Standard American Diet or some combination of the above.

          We place everyone regardless of symptoms on an animal based ketogenic diet, high in fat and moderate protein with minimal vegetable and no fruit. They all get well. All the autoimmune diseases, type 2 diabetes, metabolic syndrome, degenerative brain disease, obesity, IBS, are eliminated or improved significantly.

          Ultimately, their diet becomes an organic, pasture raised, local, in season diet. Their primary energy source is fat, adequate animal protein with limited local seasonal leafy greens and fibrous vegetables, usually fermented, and local fruit in season. This limit carbohydrate to less than 50 grams a day, with many days less. Some fruit in season days slightly more.

          No grains, bean, starch, vegetable oils, processed foods. To prove the safety of the ketogenic diet I experimented on myself for several years by staying in ketosis. I remained perfectly healthy the entire time.

          Of course, over the vast time of our evolutionary history, and with the billions of people alive today, there are many diets that we are able to survive on. I want to thrive, not survive. And so do our patients. The diet I presented here we feel is the best and has proved successful in every application. If you eat this way your biome will be perfectly able to handle all you can throw at it, provide all required immune and digestive abilities, and work with your brain and maintain a healthy hormonal system. There may be a role to play for FS as a transitionary supplement as people move to an animal based diet but once established they should be healthy without RS.

          Thanks for all your research and comments.

          Mchael wrote on April 7th, 2014
  6. Maybe its somewhere obvious but for some reason I can’t find it, what is the RS content of raw potato per 100g potato?

    I’m not afraid to chop up some raw tater in my Big ‘ol salad everyday so I would be glad to know approximately how much to add.

    Damien wrote on April 2nd, 2014
    • Were you able to find this out? I too have been looking and can’t find it. I do the same things with my salads, and i actually enjoy the raw potatoes!

      Kyle Kreick wrote on April 28th, 2014
  7. I have a few questions please. What about the arsenic content of rice? I assume that resistant starch doesn’t feed the bad organisms as well as the good? What about konjac as a source of RS? I have seen a product called Slendier Organic Konjac Spaghetti in Ocado in the UK. This is pre-cooked, so how would that affect things? Parboiled rice has RS, but what about after it has been cooked? Do we have to then cool it? What about cooked & cooled tapioca? Is tapioca flour the same as tapioca starch? What about mung bean sprouts? Also, please be careful when cooling & reheating rice. Uncooked rice frequently contains bacteria called Bacillus cereus. These bacteria can form protective spores that survive the cooking process. If cooled slowly, these spores can germinate, grow and produce an emetic (vomit inducing) toxin. Reheating rice before serving will not inactivate the emetic toxin or kill all the bacterial cells, so the rice may not be safe.

    Christine wrote on April 3rd, 2014
    • 1. I’ve been buying California rice because there is supposed to be less arsenic in the soil.

      2. The general idea is that the good bugs (if fed) have ways to inhibit the bad ones. For example, by releasing lactic acid which yeast don’t like.

      3. Konjac is a good prebiotic fiber but is not RS.

      4. Mung bean “sprouts” have used up the starch in the sprouting process. Mung bean starch has RS.

      Okay, that’s it for me…happy hunting for the other answers!

      Energy! wrote on May 25th, 2014
  8. Very dumb question, as a tag-on to my last very dumb question.

    Mark says “600 grams of baked, then cooled, potato has around 25 grams” of RS. Is that 600 grams as in 21 ounces, as in almost a pound and a half?

    That’s a whole lotta potato. That can’t be right, can it? Maybe the potato starch is the way to go after all.

    Kathy from Maine wrote on April 3rd, 2014
  9. Going a little off topic here, but from reading Free the Animal’s RS posts, it seems there has been a shift in what we should be eating now. Up to fairly recently, it was leaning towards plenty of protein and fat, adding butter to veggies, bacon fat to potatoes all the time,etc but Richard Nikoley seems to be suggesting that fat is not particularly heathful and his latest guidelines have suggested easing up on the fat, especially with the now RS based meals we should be having. A general round up from Mark on our daily suggested menu would be good too.

    Tracy wrote on April 3rd, 2014
  10. Super awesome info Mark! Thanks for following up the other article by answering all the questions it generated!

    Karen A wrote on April 3rd, 2014
  11. Ok, still have a question or two. I’m assuming that, as with most things we care about, not all potato starches are created equal…

    When you say ‘raw PS’ do you mean it’s made from raw potatoes (never cooked) or do you simply mean don’t cook with it? Are some potato starches made raw, and some not?

    Is organic important?

    I’m not being lazy – I just spent 1hr+ trying to find out this info and my head is spinning.

    Lee wrote on April 3rd, 2014
    • It’s all raw. Not that raw/cooked matters if the end product is what we want.

      I’d say that all potato starches are created equal, for all practical purposes, regardless of process. PS is not some new, suddenly arrived food. It’s been used in Asian cooking for many years.

      OnTheBayou wrote on April 3rd, 2014
    • Lee–You are correct. You need to buy raw, unmodified potato starch. “Normal” potato starch or potato flour is not what you want–you will digest it into sugar, it will make your blood sugar zoom up, it will make you gain weight, it does not feed your gut biome in the same way. Raw unmodified potato starch is what you want. For example:

      Brad wrote on April 3rd, 2014
      • Oh good, well that cleared THAT up! Ha ha. Best of three, anyone?
        Thanks for your replies :)

        PS – In Australia (where I am), apparently potato starch and flour are the same thing, just to confuse things some more. I have a bag of ‘Potato Flour (Starch)’. So, yay. But I can get some Bobs Red Mill stuff here so I’ll look out for that.

        Lee wrote on April 3rd, 2014
  12. Sorry but all this fiddling around everybody does ad infinitum makes my head hurt. I tolerate RS. I dump some in a glass of water. Stir with one of those little whisks, glug, stir, glug, stir, glug. Done. Now on with my life. If you don’t then make changes. I know some of you are fascinated by every tiny detail, but no offense I had to back off some and skip comments most of the time. I am old. Life is too short. Take a look around. I learned that.

    Junkgrl wrote on April 3rd, 2014
    • Kudos. I tried to say the same thing, above. Too much fretting, too many unGrok smoothies. Just chug it in water, and like you say, you’re done.

      OnTheBayou wrote on April 3rd, 2014
    • I should have read this comment before posting my long whiny rant below… You’re right.

      KariVery wrote on April 3rd, 2014
  13. Hello and thanks folks for the very informative answers. I’m a bit more clued in with regard to different types of starch and their benefits / detriments, as well as much more confident now about getting the flora as diverse (and therefore balanced) as possible. I just made some kefir and plan to use it in morning smoothies. Can I take this along with acidophilus capsules? Or should they not be mixed?

    Roberta wrote on April 3rd, 2014
  14. Does it matter how long the rice & potatoes are left to cool for? Only I read somewhere else that said cooked & cooled for 24 hours. Is that right or can it be cooled for just a few hours?

    Christine wrote on April 3rd, 2014
  15. For someone with SIBO, will this help or hinder the problem of too much gut flora in the wrong place. I am usually desperate to starve the creatures, rather than feed….

    Q wrote on April 3rd, 2014
    • Visit the series on healing SIBO at Animal Pharm!

      Webraven wrote on April 5th, 2014
  16. Thank you so much, Mark! This is amazing – and you even used my question in your post! I feel so special :) I’m glad I can enjoy sushi and potato salad knowing that I’m feeding my gut bacteria.

    Laura wrote on April 3rd, 2014
  17. Hi everyone. Apologies if this question has been answered somewhere. I am wondering if it is okay to mix potato starch into a small amount of Kombucha instead of water or sparkling water, as Mark suggested. My concern is that the bacteria in the Kombucha would begin digesting the RS before it reached the colon where it is desired. Also, would either of these (potato starch or small amount of Kombucha) be considered breaking a morning fast? Thanks!

    Anton wrote on April 3rd, 2014
    • My understanding is that combining kombucha and RS should be great for helping the probiotic bugs get through the stomach and SI to the colon. Richard nickoley and Tim steel at Free The Animal certainly recommend combining the two ie prebiotic and probiotic. I personally have mixed it with yoghurt. Cheers

      Korree wrote on April 4th, 2014
  18. Prebiotic soup: 1 potato, 1 small celery root, lots of alliums (for inulin), some herbs, and enough gelatinous beef broth to make a thick soup. Chill for 24 serve and then warm gently before serving. My microbiota is happy.

    Viola wrote on April 3rd, 2014
  19. I don’t know why, but this topic is causing me stress and frustration. I just want to be able to eat food that makes me feel good and be done. So really, how important is this? Can I just get a bottom line here?

    I eat about 3-6 oz. of protein from meat and eggs, two pieces of fresh fruit, 3-6 servings of about 1/2 cup of veggies and drink a 6 oz cup of yogurt kefir almost every day. I eat sweet potatoes/yams and bananas 2- 3 times per week. Every other day I take a magnesium capsule, a b-12 capsule, a C-Q10 capsule, 1000 units of vitamin D and a big fish oil pill. Maybe once or twice month, I eat some rice or pasta, and once in a great while, I eat restaurant/junky fast food. Is this good enough??? I feel good, have energy, and am maintaining my weight. Are we done here? LOL :-)

    I don’t want to come off as too harshly critical (I Love you Mark!) or annoying, but … the whole thing that attracted me to PB was the simplicity. For some reason, this RS stuff feels really complicated… sorry to whine :-/

    KariVery wrote on April 3rd, 2014
    • Your diet is certainly fine. Of course there are always improvements. Never eat grains except rice occasionally.

      There is absolutely no reason for you to add RS to your diet. RS should be treated as a supplement to be used only in certain situations for a particular individual when indicated. As medicine, not a nutritional component of a healthy diet.

      No need to stress.

      Michael wrote on April 4th, 2014
      • Ahh… thanks! Feel much less stressed, thank you :-)

        KariVery wrote on April 7th, 2014
        • Thanks, I felt the same way too! I have been primal strict since January 1st (few cheats in between there.. literally only a few as I have a big goal in mind – 6 pack by my 30th birthday) and I love the simplicity of primal. This jacks me up in the head! But I will not stress about it, knowing that RS does not need to be added.

          lisa wrote on April 11th, 2014
  20. so if cassava has resistant starch when cooked and cooled, I am assuming that the cassava cake I make (grated cassava, eggs, coconut, coconut milk and tapioca with a little honey) that is baked and then stored in the fridge would be feeding my gut flora – resistant starch from the cassava, inulin from the coconut :-). It tastes good too!

    salixisme wrote on April 3rd, 2014
  21. I love sushi. All kinds. Of course not with the fake crab or anything tempura. But what is better than raw tuna or swordfish, mahi mahi even. Yum. I make it at home so I know exactly what is going in each roll. A word to the wise however, traditional sushi rice calls for cooking the rice in sugar water. Seems like a waste to me, but I suppose it has something to do with the “stickiness” that is desired. So before you go picking up pre-made rolls make sure to check the label, or better yet, make it yourself!

    Sara wrote on April 3rd, 2014
  22. I am concerned about eating raw tapioca starch after reading this – Cassava should never be eaten raw as the root composes small quantities of cyanogenic glycosides, especially hydroxycyanic acid. Cyanide compounds interfere with cellular metabolism by inhibiting the cytochrome-oxidase enzyme in the human body. Peeling followed by cooking ensures them safe for consumption by removing these compounds.

    Christine wrote on April 4th, 2014
  23. I don’t understand what difference it makes for digestion whether you eat rice or baked potato, cold or hot?

    Paul wrote on April 4th, 2014
  24. Green bananas don’t stay unripe for long
    (I am talking regular bananas, not plantain).

    If I chopped green unripe bananas and freezed them,
    and then took them out of the freezer and ate/blended them,
    what would their RS content be?
    Same, higher, lower than if I had had them “fresh”?


    cis wrote on April 4th, 2014
  25. hey..
    i am a bit confused.. i am doing carbbackloading and i have phases where i eat extreme high in carbs & super low in fat and then times where its the other way around.. during the low carb phase i would like to start eating some resistant starches, since from what i understood they wont raise my insulin and wont kick me out of the ketogenic state.. (am i correct?).. here is my question.. before i start implementing more starches into my diet i have to make sure i understand the differences between starch and flour since i have to make sure that i eat less than 20g of carbs during the ketogenic phase.. so what exactly is the difference? is there a starch of everything you can find as a flour? is tapioca flour and tapioca starch the same (someone mentioned it in a comment)? how do you extract the starch of the vegetables?

    nobu wrote on April 4th, 2014
  26. So if 25g of the 30g carbs in a banana is RS, do you still count all the calories of the banana? or would it actually go from ~120cal to just 20cal??

    Hiya wrote on April 5th, 2014
    • Wikipedia counts calories from resistant starch at half+ of normal, digested starch.

      “Natural resistant starch delivers between 2-3 kilocalories/gram (8-12 kilojoules/gram) versus 4 kilocalories/gram (16 kilojoules/gram).”

      Notice these won’t be in your carb budget, but more into fat budget, as the bacteria converts resistant starch to fats, so the energy is available to the organism as fat.

      GTR wrote on April 5th, 2014
      • Whoa wait, so RS is converted to fat? I thought RS just “passed thru you”, i.e. was not converted to energy. Wouldn’t that mean it is actually 9cal/g?

        Hiya wrote on April 6th, 2014
  27. My husband is having problems with kidney stones. Is there a natural way to help prevent them? Is there natural meds he can take to not get them? He has tried staying away from foods that may cause the them but no luck.

    Amanda wrote on April 5th, 2014
  28. Thank you so much for addressing my question and directing me to Dr BG’s! Her blog has pulled it all together for me (I’ve been reading it two days straight :-) and I have started implementing her advice. The interesting thing is that I haven’t tolerated PS or SBOs individually, but in combination they seem to treat me well!

    Eternally grateful for the link and this series! A messed up gut ain’t no joke, and having been there for 10 + years I am so looking forward to fixing it!

    Webraven wrote on April 5th, 2014
  29. In the process of heating/cooling, can you manipulate the temperature to increase the amount of RS created? i.e. Could freezing my rice be better than refrigerating it? What about length of time the food is cooled for? Will that affect the RS level?

    JoseiTonbo wrote on April 6th, 2014
  30. hey.. i have been using potatostarch and tapioka starch for the past days and i was wondering why does starch give you a feeling of satity even though you dont extract any energy from it?

    mike wrote on April 8th, 2014
  31. The big ‘LOOKOUT!’ with sushi (rice based sushi, like hand rolls etc.) is that the rice is sweetened with plain, ol’ sugar, as well as the vinegar. It’s the most basic recipe, and rarely varied. If in doubt, ask them what’s in the rice. If they pull out a bottle of sushi seasoning, it’s absolutely got sugar.
    I cannot go near any of this kind of Japanese food for that reason- it sets me off on a bender, my hunger signals and cravings get totally messed up. It only took a minute of investigation to find out why…

    Sacha Fisher wrote on April 9th, 2014
  32. What about those of us who want to be in mega fat-burning mode? Should this be something we generally avoid still, like potatoes? I am in “I wanna be hot and ripped” mode – currently less than 60 carbs a day, usually end up around 40. F/P/C ratio is generally 60/25/15. Working out 6 days a week (mostly weight training, yoga, and light cardio, maybe once a week I’ll do the equivalent of sprinting for cardio). Because I have IBS and sometimes other digestive issues, I became curious about this. I just tried this out and had some sushi for lunch. I am not sure how many carbs to count for the day, and again, if I should avoid in general right now?

    lisa wrote on April 11th, 2014
  33. Allison Filderman wrote on April 21st, 2014
    • I wondered the same thing. I found their customer care said it is “unmodified” by virtue of the fact that it is organic. However, they also stated that the product is heated when cooked and dried.

      Christy wrote on June 18th, 2014
  34. Μаgnifiqսe article : continuz comme cela

    web page wrote on May 8th, 2014
  35. Just wondering why reheating a previously cooked potato preserves the RS but heating unmodified potato starch destroys it? Isn’t the potato starch an extract from the potato and therefore the same substance?

    Chris wrote on July 25th, 2014
    • Chris – Without getting into the science, reheating previously cooked potato or not, modify the starch and nulls it RS properties. The starch is beneficial only when cold. So next time, cook your potato, let it cool completely and incorporate it into an egg salad. You can also peel a small potato and eat it raw, or grate it, squeeze it’s juices over a bowl and drink the starch (add the grated potato to a green salad). And if on occasion you decide to cook it with eggs, I don’t think that the sky will come crashing down; remember the 80/20 (or 90/10) rule?

      Time Traveler wrote on July 25th, 2014
  36. Butyrate is the driver for a DNA mismatch that is proven to lead to colon cancer.

    Anna Russell wrote on July 29th, 2014
  37. This is great stuff…. when first diagnosed with diabetes, I was sent to a nutritionist who highly chastised me when I said I would just stay away from grains (she said if I had to avoid a whole food group to reduce my blood sugar, something else was wrong…LOL…. whoooo-boy… don’t we know it!!!!) Meanwhile, intuitively (my sister &) I have eaten raw potatoes since childhood as a crunchy snack. People think I’m weird & how could I do that, but they’re appealing to me. Also, I detest bananas that don’t have some green on them (as far down the stem & into the body of the skin as I can find)…. Nix on the freckly ones…. jeez, if we’d only LISTEN to our bodies we wouldn’t be in these fixes…. I’d like to give a tip of the hat to Dr D’Adamo, who my nephew studied with at Bastyr years ago….he proposed that blood type & diet had a correlation. Being a type 0 (the oldest blood type–hence PALEO), I can see where the grains just don’t fit in. My nephew (also a naturopath) forsook the wheat grains long ago…
    Anyway, it is nice to know I am not psycho in intuitive beliefs and that more and more studies are showing that eating THIS way works (PS….just following a very loose paleo diet for 4-5 days, my fasting BG dropped 30-40 points). Take that, mainstream nutritionist!!!

    Dawn K wrote on August 9th, 2014
  38. BLOOD SUGARS are up
    I started with a little potato starch- however my hand pain flared up (nightshade sensitivity). So now I’m buying green plantain, pureeing them with a bit of cinnamon and a drop of vanilla stevia and drying into crackers.
    Certainly there was ‘fartage’ as I increased the dose- my issue however is that my blood glucose levels are spiking soon after- and the RS intake has not blunted my glucose response to other carbs as fat as I can tell. Have also gained some weight over this past 2 or 3 weeks of trialling cold potato and cold legumes.
    I just ate around 2 Tbs of plantain cracker after a coleslaw and avocado and mayo lunch and my reading is around 130. I’m suspecting it comes down to the amylase gene issue- I shall revisit my 23andme to see what comes up there.

    Jillaine wrote on October 7th, 2014
  39. Hi sir i am pradeep. I am 27 years old but my weight is 57. I am looking very slim. I want to increase my body weight. If i increase my weight can i have plantain banana daily. Pls i want your advice.

    pradeep wrote on November 11th, 2014
  40. So, when you cook rice, should you drain it and wash the excess starch off of the rice with water before cooling it? Or do you drain it without rinsing the excess starch off and then cool it?

    Sarah wrote on December 3rd, 2014

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