March 24, 2015

Resistant Starch, Gut Health, Weight Loss, and the Infernal Internet Rathole

Who you callin' resistant?
photo by Alan via flickr

Eons ago, I posted about Resistant Starch, which was then being touted by Prevention Magazine as a miracle weight loss cure.

Basically, certain kinds of starch aren't easy to digest. Even though these stealth starches may seem all fluffy and yummy and potentially evil, like white rice and potatoes, if eaten in the right forms they can actually act in a beneficial non-carby way.  They are said to blunt blood sugar spikes, feed beneficial gut bacteria, and perform a host of other health and fat-eradicating miracles.

There was some actual research to back some of this up, but in my view I'd felt Prevention was totally over-hyping it. They were acting as though adding a slightly greenish banana, some potato salad, and a dollop of hummus to your diet was going to magically turn you into a fat-torching superhuman. I was skeptical, but I confess I did coincidentally start to buy bananas on the greener side for a few weeks.

And then, as is so often the case with any overhyped health or weight loss trend, I pretty much forgot all about it.

But now, guess what? Resistant starch is back.

It's All Kombucha's Fault

Is Kombucha a resistant starch? No, of course not! It's a probiotic fizzy concoction made from tea.

But as I was researching the purported health benefits of Kombucha for a blog post, I wandered onto various websites and blogs discussing research about fermentation and gut health. Which somehow led to resistant starch, then I started clicking links and more links and more links and before I knew it... I fell headfirst into the gurgling google abyss, swallowed up by a vexatious vortex of promising studies and conflicting claims and amazing anecdotes and spiteful flame wars until I was finally spit out days later (let's keep the analogies oral rather than otherwise, ok?),  thoroughly bewildered and confused, but ever hopeful of miracle cures.

So there did seem to be some consensus. Mostly about the sorry state of the nutrients in the stuff we eat in modern times, and the tragic results for all the "good" critters that should be in our guts.  And also some agreement about how having too many of the wrong bugs or not enough of the right ones, or having the bugs in the wrong places, can mess with our health. Whereas having a healthy diverse community of the right kind of bacteria in the right places can mean less inflammation, a better immune system, resistance to obesity, and a defense against all kinds of tiresome or dangerous diseases.

What's more controversial is whether resistant starch can fix all this by feeding the good bacteria, which then crowd out the bad bacteria, improving a whole host of health problems in the process.

Learn More About Resistant Starch

There is a lot of interesting discussion and research out there!  And if I were a more responsible helpful health blogger and not such a lazy slacker, I'd pull each fascinating nugget and contentious claim out of every source so you'd know exactly where I got it, and then I'd integrate all the information into a smooth-flowing narrative that told you everything you ever needed to know about the proper care and feeding of your micorbiome for optimal health.

Well, screw that. It's a lot of work and I find myself strangely, um, resistant.

Instead, let's do it this way:  If you are only kinda-interested, you can skip all this and maybe skim my possibly misinformed thoughts about it all below.

But if you are actually intrigued about the whole resistant starch thing, and even thinking of modifying your diet to include more, you should probably read some of these sources yourself and do some independent research. Or, if you have an unusually well-informed doctor, ask her what the heck she thinks.

Resistant starch fan club:

Mark's Daily Apple on resistant starch.

Today's Dietician on weight control, insulin resistance and resistant starch.

Chris Kresser resistant starch benefits.

Free the Animal with a resistant starch primer.

A more cautious/skeptical take on resistant starch: 

Digestive Health resistant starch discussion.

More resistant starch info from Digestive health.

Animal Pharm resistant starch cautions... part one of many.

What Are Some Possible Benefits Associated With Resistant Starch and a Healthy Gut?

Just pulling out a few examples some of the sources above:

When intestinal bacteria get to work on resistant starches, they create short-chain fatty acids, which is apparently a good thing. The environment for "good" bacteria improves, and they can then do stuff like produce vitamins, detoxify potential carcinogens, and activate healthy bioactive compounds. They also stimulate colonic blood flow, prevent constipation, lower the pH of your poop, and generally decrease the risk of colon cancer. Resistant starch may also increase satiety better than some other fibers.

Healthy gut bacteria may also help prevent diseases other than colon cancer too, like Crohn’s disease, ulcerative colitis, diabetes, obesity, and immune and inflammatory problems like rheumatoid arthritis.

There may even be a connection between intestinal bacteria and anxiety, depression, obsessive-compulsive disorder, ADD, autism, and Alzheimer’s disease.

Anecdotally, people in forums also report better sleep, more calmness, vivid dreams, and a bunch of other stuff that seems to make them glad they started eating more RS.

What Are The Sources of Resistant Starch?

There are four kinds; and this time I'm going to copy verbatim from wikipedia because I'm thinking any website that starts with the word "wiki" is probably unlikely to sue me for plagiarism. But the same info seems to be everywhere:

  • RS1: Physically inaccessible or digestible resistant starch, such as that found in seeds or legumes and unprocessed whole grains
  • RS2: Resistant starch that occurs in its natural granular form, such as uncooked potato, green banana and high amylose corn
  • RS3: Resistant starch that is formed when starch-containing foods are cooked and cooled, such as legumes, bread, cornflakes, potatoes, sushi rice or pasta salad. This kind occurs due to retrogradation, which refers to the collective processes of dissolved starch becoming less soluble after being heated and dissolved in water and then cooled.
  • RS4: Starches that have been chemically modified to resist digestion. This type of resistant starches can have a wide variety of structures and are not found in nature.

There is a more detailed resistant starch chart over at Free the Animal.

Crabby's Muddled Thoughts and Take-Aways From All This:

1. We hear a lot about beneficial probiotics, and many folks dutifully swallow pills or eat yogurt or whatever to get these good bugs in their guts.  But very few of these saintly bacteria actually survive the digestive process.

2. Prebiotics feed the bacteria we want in our systems and help them colonize. There are many different kinds of prebiotics and it's probably not a bad idea to get a variety of them. (Like dark chocolate, for example. Seriously, it's a good one!)

3. However, there is something special about resistant starch that seems to really helps the good bacteria that lead to so many health benefits.

4. Studies seem to show beneficial results come with a lot more than we typically get from food, unless you have some sort of perverse raw potato or green banana fetish.  The exciting studies seem to involve upwards of 30 grams per day, which I think is about 4 tablespoons of unmodified potato starch--one of the easier sources to supplement with.

5. Paleo and other low-carbers may not be getting all that much resistant starch naturally in their diets.

6. No one seems all that crazy about using the engineered kind in hi-maize corn, perhaps on principle, because it sounds kinda Frankensteiny.  But otherwise it seems like it may be wise to get a mix of the different kinds of RS, and accompany the starch with other sources of fiber and prebiotics as well, or you may skew your gut population in an unnatural way.

7. If you decided to supplement you should start slowly, with perhaps a half teaspoon, and work your way up. Gas is a commonly reported side effect.

8.  People with SIBO or IBS or GERD or other digestive problems may actually get worse (though some say they got better) when upping resistant starch, so should probably check with their doctors first and use caution.

Experiment in Progress

So yeah, I couldn't help it... I got tempted by all the promising studies and decided to try it out.  So now I'm spooning out potato starch and popping probiotics. I alternate between a couple of different formulas.

And I'm making sure when I eat rice or beans or potatoes that I chill them after I cook them. (Although I do find them tastier if I warm them up again to barely past room temperature. There is a difference of opinion about whether and how much reheating is allowed depending on who you read). However, I tend to go for the blue/purple varieties of potatoes and rice now that "forbidden" rice is easier to find. Which may or may not affect the levels of resistant starch negatively, I need more info on that.  But by now I'm too trained to look for the anthocyanins that go with blue food because they're also hella good for you.

It's too early to tell if I'm altering my gut in a helpful way--I'm up to about 2 tablespoons a day, and can report that gas, bloating, and a "bulking" effect are indeed possible side effects.  I'm thinking I'll give it a couple of months and maybe even spring for one of those microbiome tests to see what the heck is living in my intestines.  But then as we've established, I am more than a little nutty.

Any of you guys ever purposefully upped your intake of resistant starch?


  1. Hmm....interesting stuff. I think I will head over and read more of the articles you linked. I had a baked potato for lunch but if I'm understanding correctly it wasn't supposed to be hot. (and probably not covered in butter and cheese:(

  2. This is actually the first I've heard the phrase. I'm glad YOU are taking on the task of experimentation, because the last thing I need is something that will cause more gas. Ahem.

  3. Not on this bandwagon yet, although i've taken a very good probiotic for years. It's certainly fascinating, and heaven knows there's more to learn that we will ever get to the bottom of in a dozen lifetimes.

  4. (Where'd my comment go?!?)

    Nope - this is the first I've heard of it. Although I am glad to hear my life long love of green bananas may have an actual health benefit. I eat one (nearly) every day!

    1. I, too, prefer my bananas on the green side, though not totally green. As a child I liked raw potato, but not any more. I don't like my cooked food cold, though, so I will probably skip this part.

      Mary Anne in Kentucky

    2. ["An error occurred while publishing your comment" except, there it is. Huh?]
      Mary Anne in Kentucky

  5. OK I am going to have to read these refernces again later. I am excited by the idea I could eat potato (I like raw potato actually) and rice as I am going crazy with all this yogurt for my gut. A lot of this reads like the magic cure that I have been promised so many times but which never materializes.

    Right now I am already drained today from reading about HAES and conflicting studies regarding that.

    You know if I want to be confused and worn out I can just do my taxes!

  6. It's always cost-benefit. I wonder if the actual intake of resistant starch offsets the extra carbohydrates and the associated calories. Worth a moderation. Thanks for the article.

  7. I am so glad you are out there and willing to try these exciting experiments!!! I will resist.

  8. Can't wait to hear how this turns out for you.


  9. I haven't as such, but I let my morning brekkie potatoes cool a bit, so I am thinking of it. That said, I love raw potato, but rarely indulge. Now I can. Yay!

  10. I will let you carry on with the testing. I toot enough as it is from the foods I eat & occasional bloating so.. carry on & report back! :)

    Very interesting though! I just saw a news story on this.

  11. OH
    where have I BEEN?
    I had no idea it was back. are legwarmers back to?? pagers?

  12. "Well, screw that. It's a lot of work and I find myself strangely, um, resistant." LOL, I <3 Crabby.

    This RS thing is a new one on me. I've just focused on eating a good balance of foods while trying to avoid too many sugary doom bits (dang that candy), and that's worked out great for my gut so far. I'll leave the kombucha and starch experiments to the experts for now. :-D

  13. I've pretty much given up on the magic recipe for weight loss. I know what makes me lose weight: being hungry all the time, and that's not in the cards.

    On the other hand, I am constantly on the lookout for things that will keep me (sorry if it's TMI) regular. Drinking gallons of water and eating high fibre just isn't enough. When I have to take medication and the label warns of diarrhea, it's never an issue. My problem is that the system shuts down if I blink the wrong way.

    In my quest for regularity, I have come upon two helpful products: magnesium/calcium tablets and probiotics. I've been taking a probiotic tablet every morning for over two years now, and while it's not always a slam-dunk, I think it has helped my system to work better. I've also had a drastic reduction in colds during the winter (oops, hope I haven't spoken too soon). Correlation or causation? Dunno, don't care.

  14. Thanks, I didn't know much about this! My diet seems to have resistant starches in it. It's interesting that I've always preferred less ripe bananas, and eat a high percentage of raw foods.

    If corn starch is a RS I guess I'll be more okay with the Chinese food that I get which has that.

  15. (hanging head in shame) The only starch I concern myself with is the starch I use to make appliqué pieces for my quilts ... and sometimes the hubby's shirt collars. I shall watch and see what YOU report. :D


Thanks for commenting, Cranky Fitness readers are the BEST!

Subscribe to comments via RSS

(Note: Older Comment Threads Are Moderated)