Are potatoes really that bad?

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Rucifer
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Are potatoes really that bad?

Post by Rucifer » Fri Nov 27, 2009 12:49 am

I know this is primarily a low carb website and potatoes would seem to be the arch-nemesis of that, but are potatoes really warranting the reputation they are getting as of late? And I am not talking you know, potato chips, french fries...but simply a baked potato. If you look at the nutrition of a potato they seem to be pretty nutrient dense. I heard one guy putting them on the same level as sugar or white bread...and it just didn't sit well with me. Wanted to know what you guys think.

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Post by NightFaLL » Fri Nov 27, 2009 12:54 am

I've read that potatoes have one of the highest satiety indexes, which means even if they're calorie dense - they're more likely to make you fuller for longer.

I'm also a recreational powerlifter/bodybuilder and I eat them all the time, during a bulk or a cut and can easily maintain ~10% bodyfat with them being a large portion of my diet.

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Post by TimD » Fri Nov 27, 2009 6:00 am

No, I don't think potatoes are inherently bad. They are a good source of vit/min (skin) and provide carbohydrates. However, they are calorie/carb dense and the same amount of veg would provide more vit/min. That said, if you feel like having a potato, just keep a lid on the volume/size.
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Post by stuward » Fri Nov 27, 2009 10:12 am

Some of the nutrients and fibre are in the skins. Most people don't eat the skins. Almost all the published data assumes the skin is left on.

There are only about 20g of carbs in a potato. Except on a very low carb ketogenic diet, you can easily include a potato in your diet as long as you don't include french fries.

Nutrition Data's Fullness Factor and the Saitity Index seem to be in disagreement when it comes to potatoes. I'd say more study is required.

http://www.nutritiondata.com/topics/fullness-factor

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Post by Wouter » Sun Nov 29, 2009 4:40 am

Just a little side information:
If you cook a potatoe and eat them cold, it'll contain more fiber and less easily digested carbs than when you eat them right after you cooked them.
(I think this happens with spaghetti and everything like it too)

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Post by Rucifer » Sun Nov 29, 2009 4:44 pm

Wouter where did you read that at? I'm not saying I don't believe you just curious.

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Post by hoosegow » Sun Nov 29, 2009 5:36 pm

I don't mean to sound like an ass Wouter, but that makes absolutely no sense. How can a lower temperature magically increase fiber and decrease carb levels? Sorry bud, but I couldn't think of a nice way to say it. I mean no offense.

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Post by Wouter » Mon Nov 30, 2009 11:15 am

Just learned it in school, you can say a lot of bad things about dieticians, but they do know some things which most others don't know :wink:
I don't know the correct English terms but I'll try to explain:
When you heat up potatoes (or any other carb source, like spaghetti etc)
it'll take water in it's cells. At about 75°C the cells become 4-5x as big, the cellwalls can't take it anymore and they'll crack (but still remain intact).
I think this is called 'pregelatinization' in english but correct me if wrong. If you continue to heat them up (above 95°C) they'll crack competely and the cell is 'destoyed'. (gelatinization)
When this happens, your body is able to digest potatoes (I'm not really sure if you can't digest them before cooking, but it'll certainly be much harder). If you let the potato cool down, then the starch will cristallize again, but the won't return to their former form, since the cells are destroyed. This means that they are still digestable but not as easily as when they were just cooked (this process is called retrogradation).

And while I'm at it: here are 3 types of starch.
RDS: rapidly digestable starch (just cooked starch), fast digestion
SDS: slowly digestable starch (mostly raw vegetables), slow but complete digestion
RS: resistant starch: no digestion (fibre)
- RS1: fysical unaccesible starch: coarse grains and seeds
- RS2: resistant starch (something like this, can't translate it properly): raw potatoes and bananas
- RS3: retrogradated starch: cooled potatoes, bread, ...

So you can see that cooled potatoes contain RS3 starches.

Type of starch /100g starch (not for 100g of vegetable):
cooked (warm) potato: 65%RDS, 5%SDS,5%RS
cooked (cold) potato: 53%RDS, 11%SDS, 10%RS

It's not an enormous difference, but it is some difference and I hope it's explained pretty well and written in good English.
And, Hoosegow, I hope it does make sense now and that some of you have learned sometyhing new :grin:

EDIT: It's almost the length of a KPj post :lol:

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Post by hoosegow » Mon Nov 30, 2009 12:33 pm

I'm intrigued. According to my NutriBase Food Counts book:
1 baked, flesh and skin, 2 1/3 X 4 3/4 inch potato contains 220 calories, 5 g of protein, 51 g of carbs and 5 g of fiber
1 raw, flesh and skin, 2 1/3 X 4 3/4 inch potato contains 160 calories, 4 g of protein, 36 g of carbs, and 3 g of fiber.

There is no statement on a difference between hot and cold cooked potatos.

Where does the added nutrition come from if it doesn't come from fiber, though the fiber count actually increases?

I'm still not buying the cooling effect, though now I'm not saying it is magic. I completely understand the difference between the digestability of cooked and uncooked potatos, though I don't understand where the increase in nutrition comes from.

Keep explaining Wouter and if you have any documentation, post that if you don't mind. Like I said, I'm definitely intrigued now.

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Post by stuward » Mon Nov 30, 2009 12:35 pm


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Post by stuward » Mon Nov 30, 2009 12:37 pm


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Post by frogbyte » Mon Nov 30, 2009 3:02 pm

hoosegow wrote:Where does the added nutrition come from if it doesn't come from fiber, though the fiber count actually increases?
Well some of the indigestible starchy compounds will be converted to digestible carbs by cooking. I didn't realize you could get even that many calories from a raw potato.

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Post by hoosegow » Mon Nov 30, 2009 3:40 pm

My apologies, but a calorie is a calorie (I know, I know digestibility comes into effect). In chemistry, a calorie is simply a measurement of heat required to raise one gram of water one degree celcius. Wood has a bunch of calories, they are all mostly indigestible, but if you run your experiment, it would still have a bunch of calories. When you see calories on a nutrition label, it doesn't matter if it is digestible or not.

Am I thinking on pure chemistry terms? I'm not arguing indigestible compounds can be converted to digestible compounds by cooking. I can't disagree with that. Did I miss the memo that nutrition labels are only printing digestible nutrients and they can omit indigestible nutrients? I also am having a hard time understanding the mechanism in which a cooked starch loses nutrition after it cools. I also don't understand how a raw potato can have less base nutrients (once again I'm not talking about digestible nutrients) than a cooked potato. I mean, how in the hell does a cooked potato gain 2 g of fiber?

Dang it! I feel like I am about to learn something here.

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Post by Wouter » Tue Dec 01, 2009 1:46 pm

It seems like too much of a coincidence, but T-Nation just posted an article about carbs (haven't read it though, just the first few sentences)
http://www.tmuscle.com/free_online_arti ... bout_carbs
The first topic looks like it has a lot to do with the topic we're dicussing.
But I don't have the time right now to (try to) explain some more.

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Post by frogbyte » Tue Dec 01, 2009 3:34 pm

A calorie is not a calorie. The calories per gram of certain substances vary from country to country because they decided on different government standards.

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