Resistant Starch - A Solution In Search of a Problem page 5

[Paleobird]

Wow. Otzi was just schooled in Biochem.
Thanks for the posts, Pklopp.

Yep, Otzi. Read and learn, my friend. PK knows his stuff.

Take a look at the red arrow, which tells us that 2% of the starch in a boiled potato is resistant. So, of that 35 grams of starch, you're looking at a thoroughly underwhelming 0.7g of resistant starch. I find that the proportion of resistant starch attributed to potatoes tends to directly and positively correlated to how hard one is trying to convince you to eat an all potato diet.

Of course, the undisputed champions of resistant starches are beans and legumes, so if flatulence is your cup of tea, you know what to do.
-PK

No, thankyouverymuch.

This whole thread makes it look like PK is comparing RS to unicorns. RS definitely exists, and is definitely being studied for health benefits...undisputed facts.

Bran has been extensively studied for its health benefits too. Does that mean I need some? I think not.

PK is not saying that rs doesn't exist, just that it is not something that everybody must have large quantities of right now or face dire health consequences. It's just not that important one way or the other.

[otzi]

Yep, Otzi. Read and learn, my friend. PK knows his stuff.

I guess there's only one way to settle this. You and PKlopp go out of your way to avoid RS, and I will go out of my way to get RS. The first one to get bowel cancer owes the other $5. Deal?

but first read: Resistant starch may offer potential to help protect against bowel cancer

"These new studies suggest that increasing the amount of resistant starch in our diets may be one important step along the path to reducing the burden of bowel cancer. It takes about 15 years from the time of the first bowel cancer-initiating DNA damage to the development of full-blown bowel cancer, so the earlier we improve our diets the better," Dr Lockett said.

The recommended intake of resistant starch is around 20 grams a day, which is almost four times greater than a typical western diet provides. Twenty grams is equivalent to eating three cups of cooked lentils.

"Currently, it is difficult for Australians to get this much from a typical diet," Dr Topping said.

"We have already had success in developing barley with high levels of resistant starch, and now our focus is on increasing the levels of resistant starch in commonly consumed grains like wheat. These grains could then be used in breads and cereals to make it easier for Australians to get enough resistant starch from their diet."

Resistant starch is a component of dietary fibre that resists digestion in the small intestine and instead passes through to the bowel where it has positive effects on bowel health. Resistant starch is sometimes called the third type of dietary fibre (in addition to soluble and insoluble fibre) and is found in legumes, some wholegrain breads and cereals, firm bananas and cooked and cooled potatoes, pasta and rice.

[pklopp]

Lessons in Crafting A Muddled Argument, as presented by Prof. Otzi:


1) Start off with a mild insult:

This whole thread makes it look like PK is comparing RS to unicorns. RS definitely exists, and is definitely being studied for health benefits...undisputed facts.

I'm sorry, what? Where did that come from? This must be what students of literature refer to as "poetic license."

2) Reiterate an undisputed piece of data, but make it seem controversial:

As to the amounts contained in potatoes, I can't see where you are coming up with such low figures. From your chart, it shows that (far right column) nearly 100% of a potato carbs, no matter how it's prepared, are potentially available as 'starch'.

Since I love Wikipedia, we'll go there for details at Potato - Wikipedia, the free encyclopedia

A typical potato weighs about 250g (1/2lbs), and contains 17g per 100g of carbs, or 42g of carbs, of which nearly 100% is starch (from your chart, far right column)

Ok, Otzi. Your abilities to cut and paste from Wikipedia are unparalleled. I plead no contest to this.

3) This is the critical step, where you make up a number, and attribute it to nameless, faceless sources, the infamous "they" of "they say" fame:

I have seen it said, that the RS in a raw potato is approx 75% of available starch, so the typical raw potato has about 30g of RS.

Where have you seen it? Who said it? When did they say it? Keep in mind that under a strict interpretation of this sentence, you reading your own post where you claim that 75% of available starch is resistant starch qualifies as "having seen it said", albeit in a completely unsatisfying fraudulent way.

I can just as easily claim, unsubstantiated of course, that I have seen it said that potatoes are long term metabolic poison.

It looks to me like your chart is showing 100g serving sizes, which is like less than half a potato.

Nope, it's this sciency thing called percentages.. The way they work is, you use them to multiply stuff. So, as an example, when it says 2% of starch in a potato is resistant and then you say an average serving comprises 35g of starch, then you multiply .02 x 35 and you get 0.7g of that 35g of initial starch is actually resistant.

You may also take note of the fact that the people who say 2% of the starch in a Swedish potato is resistant starch happen to be the fine folks at the Department of Applied Nutrition and Food Chemistry, Center for Chemistry and Chemical Engineering, Lund University, not some nameless, faceless "they."

My whole point here is that the SAD contains some RS, from potato chips, beans, grains, and other off-limits Primal Blueprint foods. When we switch away from the SAD to a healthier paleo style diet, we remove most, if not all, RS. Eating potatoes and rice will get some RS back into your diet. Eating cooked and cooled potatoes and rice will get even more, and eating raw potato will get a whole lot.

That's an interesting point, and I generally agree with it. I have no idea how you arrived at the recommended intake of resistant starch when it is generally accepted that the average American ingests on average 4g of resistant starch per day ... I have seen it said, but I'll pull up the reference for you.

-PK

[otzi]

3) This is the critical step, where you make up a number, and attribute it to nameless, faceless sources, the infamous "they" of "they say" fame:

Quote Originally Posted by otzi View Post
I have seen it said, that the RS in a raw potato is approx 75% of available starch, so the typical raw potato has about 30g of RS.
Where have you seen it? Who said it? When did they say it? Keep in mind that under a strict interpretation of this sentence, you reading your own post where you claim that 75% of available starch is resistant starch qualifies as "having seen it said", albeit in a completely unsatisfying fraudulent way.

I can just as easily claim, unsubstantiated of course, that I have seen it said that potatoes are long term metabolic poison.

I only have the energy to argue this one point...where I saw that raw potato contains 75%. I have seen it several places, unfortunately, I don't catalog everything I have ever read. But here is a chart I just now found. It is from Table 2 in Health properties of resistant starch - Nugent - 2005 - Nutrition Bulletin - Wiley Online Library, which, by the way you should consider reading...

Table 2. Resistant starch contents of a number of sample foods and commercially manufactured sources of resistant starch Food sample RS content (as assessed using AOAC 2002.02)

Source: Reprinted with kind permission from McCleary & Rossiter (2004). Copyright (2004) AOAC INTERNATIONAL.

Wheat bran  0.42
Rye crispbread  1.2
Kidney beans  5.3
Corn flakes  2.8
Native potato starch 78.1
Cooked and cooled potato starch  3.8
HYLON VII 53.7
Hi-maize 1043 45.7
NOVELOSE 240 46.9
ActiStar 58.0
CrystaLean 40.9

Also of interesting note, there are many 'food' manufacturing companies out there trying to GMO wheat and other grains to increase RS as well as make RS from corn and other grain products. From the chart above, raw potato blows away anything they have made so far...

And in case you say "That's NATIVE POTATO STARCH not raw potato starch, here's what native potato starch is: http://www.solam.com/index.php/produ...to-starch.html

[pklopp]

I guess there's only one way to settle this. You and PKlopp go out of your way to avoid RS, and I will go out of my way to get RS. The first one to get bowel cancer owes the other $5. Deal?

but first read: Resistant starch may offer potential to help protect against bowel cancer

You keep missing the point. I'm not debating whether RS will cause increased colonic fermentation and thereby increased SCFA production to sustain colonocytes. Read that again, I'm not discussing that, nor the benefits of a healthy colonic biome, nor whether medium to short chain fatty acids metabolize differently from long chains.

I am very interested in debating whether one needs to go out of one's way to "supplement" with RS from potatoes, for instance. I do not believe this to be the case as there are other indigestible carbohydrates which serve the exact same function from the colonic bacteria point of view ... things like fructans, inulin, and various other things that you get by eating such things as fibrous vegetables, onions, asparagus, etc. etc.

-PK

[Paleobird]

From the article you insisted we read:

Western diets are typically low in fibre and have been linked with a higher incidence of bowel cancer. Even though Australians eat more dietary fibre than many other western countries, bowel cancer is still the second most commonly reported cancer in Australia with 30 new cases diagnosed every day. Dr David Topping, from CSIRO's Food Futures Flagship, said this is referred to as 'the Australian paradox'. "We have been trying to find out why Australians aren't showing a reduction in bowel cancer rates and we think the answer is that we don't eat enough resistant starch, which is one of the major components of dietary fibre," Dr Topping said.

"Have been linked" and "we think" rank right up there with "it is said". Heart disease "has been linked" with meat consumption but do you believe it's true? Vegans will tell you about how essential fiber is and how meat rots in your colon.

Are you really buying all that CW blather, Otzi? All that is is an AllBran commercial. Rs is nothing more than dietary fiber (or fibre if you are in the UK or Oz).

[pklopp]

I only have the energy to argue this one point...where I saw that raw potato contains 75%. I have seen it several places, unfortunately, I don't catalog everything I have ever read. But here is a chart I just now found. It is from Table 2 in Health properties of resistant starch - Nugent - 2005 - Nutrition Bulletin - Wiley Online Library, which, by the way you should consider reading...

Also of interesting note, there are many 'food' manufacturing companies out there trying to GMO wheat and other grains to increase RS as well as make RS from corn and other grain products. From the chart above, raw potato blows away anything they have made so far...

And in case you say "That's NATIVE POTATO STARCH not raw potato starch, here's what native potato starch is: Production of native potato starch - Mainpage

Native potato starch is as natural as any dehydrated / freeze dried food is. The large discrepancy in your table between cooked and cooled potato starch at 3.8 ( percent, presumably, since there are no units given ) vs. 78.1 is entirely due to the industrial processing of potatoes. Hardly primal / paleo / natural.

If you are trying to console or soothe me by pointing out big Agro is interested in genetically modifying normal food to make it contain more resistant starch, then you are failing miserably.

-PK

[otzi]

I am very interested in debating whether one needs to go out of one's way to "supplement" with RS from potatoes, for instance. I do not believe this to be the case as there are other indigestible carbohydrates which serve the exact same function from the colonic bacteria point of view ... things like fructans, inulin, and various other things that you get by eating such things as fibrous vegetables, onions, asparagus, etc. etc.

-PK

I guess I did miss that...my apologies.

I think that within a Primal Blueprint framework, potatoes are a very good solution if one felt the need to increase RS in their diet.

The other things you mention: "fructans, inulin, and various other things that you get by eating such things as fibrous vegetables, onions, asparagus, etc. etc." I don't believe serve the same function, but if someone had evidence otherwise, I would be very open to hearing them.

As you can see, I have clicked many RS links. All of them describe RS as I discussed earlier in the wikipedia link with RS1,2,3,4.

I believe the key is in the starch, not the carbohydrate. There are two sorts of fiber and we need to eat both to keep the large bowel and other parts of the digestive system health. Soluble fiber includes pectins, gums and mucilage, which are found mainly in plant cells. Soluble fiber is thought to lower blood cholesterol levels. Good sources of soluble fiber include fruits, vegetables, oat bran, barley, seed husks, dried beans, lentils, peas, soymilk and soy products.

Insoluble fiber includes cellulose, hemicelluloses and lignin, which make up the structural parts of plant cell walls. This type of fiber is said to prevent constipation and hemorrhoids. Good sources include wheat bran, corn bran, rice bran, the skins of fruits and vegetables, nuts, seeds, dried beans and wholegrain foods.

Resistant starch is not fiber at all but it acts in a similar way in the body. Resistant starch resists normal digestion. Bacteria in the large bowel ferment and change the resistant starch into short-chain fatty acids, which may protect against cancer. Resistant starch found in many unprocessed cereals and grains, firm bananas, potatoes and lentils.

Primal Blueprint and paleo in general isn't a big fan of fiber.

Soluble fiber slows stomach emptying, which prevents the body from being flooded with glucose at the same rate as it would be with a low fiber meal (assuming a high glycemic load in the meal). But therein lies the pertinent question: if you maintain a diet with low glycemic load, do you really need to slow the digestion process with fiber? Hmm. If that fiber were adding a plethora of nutrients, as found in vegetables, then the answer would be yes. But as for a fiber source without all those nutrients? Not so convincing. - Mark Sisson

Read more: Fun With Fiber: The Real Scoop | Mark's Daily Apple

I personally never put much stock in fiber. Every time I tracked it I was waaaay short of the RDA. When I started hearing about Resistant Starch, I was a bit more interested. I think gut health is of UTMOST concern for all of us, and taking out a big piece of the gut health puzzle, RS, seemed to me worthy of looking into.

Mark Sisson took a jab at RS a couple years ago:

...It’s silly and not worth a lot of typing, so I’ll make it short. The thing that jumps out at me is the author’s obsession with “Resistant Starch.” First of all, I’m not sure why it deserves repeated capitalization (maybe it’s some sort of deity?), and second, resistant starch is just another type of prebiotic whose fermentation by microbiota releases beneficial short chain fatty acids. You can get the same kind of reaction by eating other sources of soluble fiber, many of them decidedly low-carb. Think leafy greens, broccoli, berries, apples, jicama, onions, garlic, leeks, Jerusalem artichokes. And yes, if your activity levels and metabolic health permit, Primal starches are good sources of resistant starch and soluble fiber alike, but it’s not the carbs doing it. It’s the “carbs” that you literally cannot digest without your little microscopic friends’ assistance. - Mark Sisson

Read more: Is Central Heating Related to Obesity? | Mark's Daily Apple

It seemed like he is down on RS, but this was just an off-hand comment about an article: 8 reasons carbs help you lose weight | Healthy Living - Yahoo! Shine

I don't think Mark has ever taken a serious look at RS, but judging by his complete endorsement of Perfect Health Diet - A diet for healing chronic disease, restoring youthful vitality, and achieving long life and all it's 'Safe Starches', I would say he's due to offer some serious insight into starch and RS.

So the question is: Can you get RS from other sources of fiber? I think the answer is "No". RS, and meaningful butyrate/SCFA/colon microflora benefits only come from RS, and one of the best Primal Blueprint RS' is potatoes, cold better, raw best, with cold rice in distant 4th place.

I think it is definitely worthwhile to purposely source and increase RS in the PB framework.

[otzi]

Native potato starch is as natural as any dehydrated / freeze dried food is. The large discrepancy in your table between cooked and cooled potato starch at 3.8 ( percent, presumably, since there are no units given ) vs. 78.1 is entirely due to the industrial processing of potatoes. Hardly primal / paleo / natural.

If you are trying to console or soothe me by pointing out big Agro is interested in genetically modifying normal food to make it contain more resistant starch, then you are failing miserably.

-PK

Not sure where this is coming from. The RS found in native starch is the same as RS found in raw potato. If a potato has 35g carbs, about 34g of them are starch with 78% being RS.

Pointed out that big agro is trying to develop this because there is a market for it. I hate the fact they are GMO'ing more foods. I think it would be a big step backwards for humanity if we all started eating GMO wheat with high RS.

[pklopp]

Not sure where this is coming from. The RS found in native starch is the same as RS found in raw potato. If a potato has 35g carbs, about 34g of them are starch with 78% being RS.

The fat found in heavy cream is the same as the fat found in milk, therefore, since the milk fat content of heavy cream is somewhere around 35%, the milk fat content of milk must be 35%.

Do I need to beat this dead horse further, or are you willing to admit that industrially processed foods are not equivalent to their natural sources?

-PK