[sci.bio] Potato Skin

mdolin@nugipsy.UUCP (01/15/87)

Does anyone know about the nutritional value of potato skins?  In the 
Pritikin program book a few of the recipies call for peeled potatoes.
I thought I remembered something about potato skins being bad
nutritionally but I can't find it in the book.

Certain "healthy" diet plans allow baked potatoes including the skin.
For example, the Diet Workshop seems to be in agreement on certain
nutritional points with Pritikin but disagrees in several other areas.
I'm under the impression that potato skin is one of them.

I'd like to know what is in the skin of potatoes and should it be 
avoided.
Regards,

Mike Dolin

(Standard disclaimer applies)

Gould Computer Systems Division
Ft. Lauderdale, Florida
.....!{brl-bmd,pur-ee,sun}!gould!mdolin

dcohen@topaz.RUTGERS.EDU (Dawn Myfanwy Cohen) (01/19/87)

     I seem to remember hearing something about the poisonous part of
the potato being the eyes or the sprouts.  Skins are fine, as far as I
know.-- 

Have Fun!

--Dawn (dcohen@topaz.rutgers.edu)

dma@euler.Berkeley.EDU (Controls Wizard) (01/19/87)

Keywords:solanine



The eyes are always poisonous; I'm not sure about sprouts but I wouldn't
eat them (remember, potatoes are related to belladonna, a.k.a. deadly
nightshade).  The skins are usually O.K. (in moderation).  The thing to
watch out for is potatoes with greenish skins.  This indicates the presence
of solanine (I may be spelling this wrong) which is the potato poison in
question.  The concentration of solanine is increased by exposure to
sunlight which is a good reason for keeping your potatoes in a cool, dark
place.  
Even eating one or two potatoes with higher than normal solanine levels 
won't do you much harm as it isn't remarkably toxic.  Besides, it makes
the potatoes bitter so you probably won't want them anyway.  The solanine
level in non-green potatoes is small enough that you would have to eat on
the order of 5 pounds a day to cause any problems.

Miriam Nadel

thoma@reed.UUCP (Ann Muir Thomas) (01/20/87)

In article <46@houligan.UUCP> mdolin@nugipsy.UUCP writes:
>I'd like to know what is in the skin of potatoes and should it be 
>avoided.

I think that it is _sprouted_ potatos that are poisonous.  The skin, or
the layer immediately under the skin of an _unsprouted_ potato contains
most of the potato's vitamin content.

-- 
"You can't help that," said the Cat, "we're all mad here. I'm mad. You're mad."
"How do you know I'm mad?" said Alice.
"You must be," said the Cat, "or you wouldn't have come here."
		Ann Muir Thomas		tektronix!reed!thoma

mdolin@nugipsy.UUCP (01/20/87)

In a previous posting I asked about the nutritional value of potato
skins.  After a little closer reading of the Pritikin Program, I found
this excerpt:  

`The potato is a splendidly balanced food.  Avoid the skins though,
which contain solanine, a toxic substance.'

What is solanine & what does it do to you?  How much can a person
stand?

I also heard that if a potato is baked and then the skins are fried, as
they are served in many popular restaurants with butter, cheese, bacon
bits,...the works -, the skin is carcinogenic.

Regards,

Mike Dolin

(Standard disclaimer applies)

Gould Computer Systems Division
Ft. Lauderdale, Florida
.....!{brl-bmd,pur-ee,sun}!gould!mdolin

cavrak@uvm-gen.UUCP (01/25/87)

> `The potato is a splendidly balanced food.  Avoid the skins though,
> which contain solanine, a toxic substance.'
> 

The way I remember it is that solanine is "produced" in potato skins
when potatos are left in the sun light.  Visually, this is indicated
by a pale green coloring sometimes visible on potatoes. The fruit 
of the potato is, again if my memory serves me, is quite poisonous.  

I suspect that this is related to the fact that potatos are
members of the nightshade family (Solanacae, along with eggplant,
tomato, red pepper, tobacco, belladona, jimsonweed, and the
garden petunia).  Palmer Fowler's "Fieldbook of Natural History", 
doesn't describe solanine but some equivalent gardening book must.
-- 
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jc@cdx39.UUCP (01/29/87)

> 
> `The potato is a splendidly balanced food.  Avoid the skins though,
> which contain solanine, a toxic substance.'
>
This is one of the nicer examples of a "semi-truth", i.e., 
a fact that is both true and irrelevant.

The green portions of most of the Solanaceae (potatoes, tomatoes,
peppers, eggplants, Jimsonweed, nightshade, etc.) contain measurable
quantities of this toxin, and in many cases the levels are high
enough to be poisonous to humans.  In other cases (the greenery
of tomatoes, for instance) there is enough to make you ill but
otherwise not very dangerous.  In still others (peppers, tomatoes)
there are low levels of the toxin, but not enough to even make
you ill.  

The green portions (and sprouts) of potatoes are in the latter
category.  True, they contain the toxin, but it's not enough to
worry about.

Some people would argue that "Well, I should obviously avoid any
food that contains even small amounts of known toxins."  If you
were to do this, you wouldn't have much in your diet.  You would
have to exclude all spices, which are all at least slightly toxic
in large doses.  Many other common foods, especially those in the 
first paragraph above, would be on the excluded list.  Also, most 
vitamins are toxic in large doses, so perhaps you should avoid them,
too.

Your body (mostly, your liver) can handle most of the common
environmental ("natural") toxins, in small doses.  Don't worry
about it.  

Well, you might toss green or sprouted potatoes.  They aren't
really dangerous, unless you eat 10 pounds in a sitting.  But
they don't taste very good.  

-- 
	John M Chambers			Phone: 617/364-2000x7304
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adams@crcge1.UUCP (Drew Adams) (02/03/87)

In article <491@uvm-gen.UUCP> cavrak@uvm-gen.UUCP writes:
>
>> `The potato is a splendidly balanced food.  Avoid the skins though,
>> which contain solanine, a toxic substance.'
>> 
> .....
>Palmer Fowler's "Fieldbook of Natural History", 
>doesn't describe solanine but some equivalent gardening book must.

The above reference is misleading.  Eve Laurence Palmer was the author
of the original edition.  I assume a Dr. Fowler was added later.
Eve Palmer was a joy to all whose paths he crossed, and the Fieldbook 
reflects well his love and familiarity with nature.