About Green Potatoes

Green = vegetables = good, right?

Not when it comes to potatoes.

Here’s an important piece of information that my mother taught me years ago, but fewer and fewer people these days seem to know about. Green in potatoes indicates the presence of a rather harmful toxin. When you see patches of green in your potatoes as you peel them, cut out the green parts entirely and discard them.

What is the green? Actually it’s chlorophyll. Not bad for you at all. But the chlorophyll indicates that the potato has been exposed to sunlight. And where the potato has been exposed to light is where a natural toxin in the potato (solanine) becomes concentrated at harmful levels. So, never store your potatoes on the counter. Always keep them in a cool, completely dark place.

Solanine is a natural defense mechanism of the potato to ward off fungus and pests. It will also be triggered when a potato is bruised, so if your potato is at all damaged or bruised, discard it.

According to the Wikipedia, deep-frying potatoes at a high temperature (306°F) effectively lowers the level of toxins. But boiling them (212°F) has no effect. Best to stay on the safe side and just cut away the green parts. The NIH website mentions that the potato sprouts can also have concentrated solanine, so those too should never be eaten.

green-potato-3.jpg

One of the things we’ve been noticing recently is that more often than not the bag of potatoes we buy from our local grocer contains several potatoes with green splotches. Once in a while is one thing, but every time? We’ve complained to our store’s manager and if you are finding green in the potatoes from your produce supplier, we urge you to do the same.

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58 Comments

  1. Elise

    This potato thing is something I would probably never know about but for my mother. There’s nothing on the USDA website about it. The potato board websites don’t mention it. If you didn’t have someone take you by the hand and explicitly tell you about the potential problem with green potatoes, you might never learn about it.

  2. Nick

    From what I’ve heard, potatoes always contain this toxin but to a much lesser extent. I wonder if the chemical builds up in your system like mercury can from eating too much tuna….I sure as heck don’t wanna turn green.

    All members of the nightshade family (tomatoes, eggplants, bell peppers, potatoes) have this toxin, but in low enough concentrations that it isn’t a problem. The toxins help repel pests. In the case of the potato tuber however, the solanine can become concentrated to harmful levels when exposed to light. Don’t know about build-up. Haven’t seen it mentioned as an issue. ~Elise

  3. Anonymouse

    True story: I was talking to my grandmother about her childhood once, and she mentioned that she’d had a very young sister who died from eating a bad potato. I thought she was joking because she mentioned that it was green and that’s what made her sick, so it’s crazy to read this now.

  4. Lalaine

    Thank you very, very much!
    We go through at least 100 lbs of potatoes at work (skilled nursing facility)on a weekly basis. This is a need-to-know info that I’ll be passing along to our cooks and to our suppliers as well.

  5. Pille

    That green potato is no good for you is pretty common knowledge here in Estonia, and I’ve known it since I was a kid. However, when I lived in Scotland, I often encountered green potatoes even in upmarket deli shops, and the shopkeepers just raised an eyebrow when I asked them about it..
    It’s good of you to highlight this issue, Elise!

  6. Sarah

    Thanks for this info. I live in Laos where potatoes are called “foreigner root”. Anyway, I’ve seen some green spots in potatoes since I’ve been here and wondered about this.

  7. Navtej Kohli

    I have faced many instances of having green potato. Though I never knew why that part comes but I used to chop it off still (just becoz it looked dirty). Thanks for sharing this information. Now I can tell others also about it.

  8. Marie

    I never realized that people didn’t know potatoes could be poisonous. It was something that I, too, learned from my mother when she taught me about cooking. thanks for putting this information out to keep people safe. also, I’ve always heard that tomato leaves are poisonous too.

  9. uwe meller

    Yes, there is a small amount of poison in green potatoes. No, you won’t die from it; there’s not enough to make you sick or kill you.

    Actually, a person can die from it, and it can make you very sick. Check out the National Institute of Health’s page on potato poisoning. ~Elise

  10. Andy

    Thanks for the advice. I had no idea the green was toxic on a potato. How toxic is it? Would it just make you sick? Could it do permanent harm? I’m guessing the answer is that it depends on how much you eat, but I am curious.

  11. Dan O

    I remember reading once that if somebody had discovered potatoes today, they might have trouble getting them approved as edible by the FDA due to the potentially dangerous solanine content. Weird to think about!
    I really wish I could find the article.
    Thanks Elise. Good info as always.

  12. Pamela

    I too have a noticed a dramatic increase in the number of green potatoes on the shelf. I can’t buy a bag of potatoes anymore without at least half of them being green. Its irritated me to the point that I’ve actually stopped buying them– why pay for 50% garbage?

    I haven’t complained to the manager yet, though– you’re right, that’s the next step! Thanks for spreading the word.

  13. Jennifer

    I had read this about green potatoes, before, and whenever I have told anyone, they’ve acted like I’m nuts! I’ll have to send a link to all the doubters!

    Oh, and I’ve noticed a huge amount of green potatoes, too, but thought maybe it was due to the discount market I shop at. (aldi’s) Those darn brown tinged bags makes it hard to tellif you have many green ones.

    I have been using the green potatoes, though, just peeling them until the green is gone, so I hope that’s okay.

  14. Joe

    Yes, solanine is toxic and it should be avoided. Should it be feared? No. According to Dr. Holt from the University of Missouri – Columbia, there have not been any reported cases of potato poisoning deaths in the US in 50 years.

    According to the International Program on Chemical Safety, and other sources, the toxicity of solanine varies from species to species but the LD50 ranges from 20mg/kg to 590 mg/kg. (LD50 is the concentration at which 50% of the sample population died, in the units of mg of toxin per kg of body weight.) Being conservative, we could take about 25mg/kg to be a safe number to use for humans.

    Also according to the Wikipedia article and other sources, the normal concentration of solanine in healthy white potatoes is 200mg/kg of potato. After exposure to sunlight the concentration can go as high as 1000mg/kg.

    So using my weight – about 150 lbs – an LD50 of 25mg/kg and a green potato solanine concentration of 1000mg/kg I would need to eat 3.75 POUNDS of purely GREEN potato to reach a dosage that would be likely to kill me.

    I’m not going to sweat the tiny bit of green potato.

    Here’s a thought that should be even more upsetting. Do you think that the potatoes that are used to make french fries, hash browns, tater tots, etc. in a huge factory are even examined for green spots? Or do they simply get peeled, sliced, packaged, and sent out to you and me? The Wikipedia article referenced above notes that the average person probably gets about 12.5mg/day, which for me is only 0.18mg/kg per day. Luckily it’s nowhere near the LD50, so I’m still safe.

  15. Imperfect Mommy

    Like many of you, I too have been finding a lot more green potatoes. I had a whole bag that was green that I had to throw out. I remember hearing about this at one point which led me to pitching them, but I didn’t know if it was really true, or just legend (and I swear my husband thinks I make this stuff up and am so overly cautious). And I wasn’t sure if it would make the whole potato bad, so thanks for letting me know that I just need to cut away the bad part.

    Funny thing, I have never found a green potato in my CSA distributions!

  16. Mary

    Thanks. I thought most people knew about this, I don’t remember where I learned it. There’s a grocery store near our house that I shopped at only once because they had an entire bin of potatoes that were green. I really needed potatoes that day and was really ticked off.

  17. Lindsay

    I did not know that. I just cut it off all the time because it looked odd, and potatoes are cheap so that bit was cheap to throw away.

    So, is a potato safe to eat if it grew sprouts that you scrubbed off?

  18. Jerold G

    Green spuds are everywhere it would seem. I avoid buying potatoes in a plastic bag altogether,as the green ones are difficult to catch. I take the extra bit of time and hand pic each potato and it pays off in spades as I never get green ones. Storage is another thing to consider. My potatoes go quickly into a dark cupboard where it is cool. Another thing. In the summer you must protect your newly purchased spuds from both heat and sun.Put them on the car floor and cover them with a newspaper or coat.

  19. Sherpa

    Yeah, my mom taught me about green potatoes years ago too. I read once a long time ago that every individual has a different tolerance to solanine, so its important to just cut out the green parts. Out here on the East Coast, I’ve noticed more green potatoes too.

  20. Lynne Finch

    I read about this years ago in Prevention magazine. If I remember correctly, you would have to consume a lot to actually get sick.

  21. inkedAG

    I never knew about this! Thanks for bringing it to our attention.

    I was wondering, since I was a kid, my mom has stored potatoes in the fridge. Is that good or bad?

  22. Stefanie

    Thank you so much for keeping us all informed. I think it is of the utmost importance to stay informed and to stand for good clean food. If green potatoes seem to be more common than before, we should definitely talk to store managers, and use our $ and energy to be outspoken about the quality we want in our food supply.
    I just walked into my friend’s kitchen and saw a whole basket full of potatoes with a green tint all around!

    I have heard that potato peels have a chemical that is not healthy. Do you know anything about that? Should we always be peeling our potatoes?

    I’m glad I found your site.
    -Stefanie

    Hi Stephanie, from what I understand, the solanine occurs mostly right under the peel. When you peel the potatoes, you remove the highest concentration areas. But, usually there isn’t enough solanine for there to be a problem, so it’s perfectly fine to eat the peels, normally. Just don’t eat the peels if the flesh directly underneath is green. Cut away those parts. ~Elise

  23. Lucy

    I found this online:
    “However, unless you are deliberately seeking out green potatoes to eat, you are unlikely to ingest enough of the toxin to do harm. The potatoes we buy contain such a minute amount of the chemical that a healthy adult would have to eat about 4-1/2 pounds at one sitting to experience any neurological symptoms.”

    True, however the same article also says, “Do discard any potatoes that have green eyes, sprouts, or greenish skins, rather than prepare and serve them, especially to children. Children’s smaller body size makes them more susceptible to ill effects.” ~Elise

  24. Guinnevere

    Do you use a potato box, then, elise, or how do you store your potatoes and onions?

    We store our potatoes in a woven basket in a closed pantry. The onions we eat up so quickly we store them in a basket on the kitchen counter. If we didn’t eat them up so fast, they would be stored in the pantry also. ~Elise

  25. Robbie

    Thank you soooooooooo much for this post. It’s like you read my mind. I used to keep my potatoes in my pantry but it seemed they sprouted eyes too fast so I started keeping them in a fruit/vegetable tree on top of my fridge. I heard refrigerating them causes the starches to breakdown into simple sugars, or some such. Recently, I noticed the greening but didn’t think anything of it but Sunday my last potatoe was solid green. I thought perhaps it was picked before it was fully ripe, shrugged my shoulders and made a mental check to find out what caused potatoes to green. I proceeded to slice it and fried it in a pan. I only ate half and froze the rest. I will most definitely throw that away and find out what the results are from consuming the toxins. Yikes!

  26. fezzik

    This is great info! I’ve always peeled away the green, but didn’t know what it was. Funny–a veggie that grows in the ground has been exposed to the sun? I’m not surprised that one poster didn’t see green in her CSA potatoes.

    Here’s the question–Potato chips–I’ve seen green ones. Has the frying process destroyed the toxin? (I know, not healthy:) I’m just curious).

    Based on the info from the Wikipedia page on Solanine, deep frying does reduce the toxins. ~Elise

  27. verily

    Thank you! I had no idea about the green parts. I always cut them away anyway, just as I cut away brown spots and whatnot, since green is obviously not a normal potato color.

  28. Amy

    Wow, good to know. I usually cut the green away if there is any, just because I’m picky. I didn’t know it was toxic, though.

  29. katie

    There is actually a potato inspector who is supposed to come through grocery stores periodically to check for this. I learned this when I worked at a small grocery store in 2005. Actually I think the guy looks at bagged produce in general, or maybe just apples and potatoes. At any rate, he complained about this to us, we were educated about it, and we removed the green potatoes from the shelves.

    Unfortunately i don’t remember where the guy was from, but somebody up in our government knows abotu this, and is probably the proper place for such complaints.

    Funny comment above about how “if potatoes were discovered today they would not be approved to be consumed due to their toxic content.” Makes you think twice about all this government regulation on our food. Let these people Eat!

  30. Deborah Dowd

    Thanks for this information- I usually cut out the green part but had no idea that their were toxins affiliated with that. I will really be paying attention and I will be sure to share this.

  31. Mr. Curiousity

    What about green potato CHIPS? You know, potato chips that have green areas on them when you pull them out of the bag?

  32. leigh

    I ate a baked potato that had a green part once. Oh dear. SEVERE vomiting and diarrhea. SEVERE. Seriously. I didn’t eat any kind of potato for a good six months.

  33. chai

    My father always taught me not to eat green potatoes, and that the whole potato should be discarded as it’s not enough to just cut away the green bit.

    As you’ve already stated the green bit is chlorophyll and indicates that the potato was exposed to light, while the solanine is colourless and odorless. According to my father it can be evenly spread throughout the potato but is most concentrated in the peel.

    So I guess if you want to cut away the green bit and eat the rest, you should at least make sure it is peeled.

  34. Ginger

    I grew up on a potato farm in NW MI and have known about green potatoes and sprouts my whole life. I recently was having a potato emergency and bought a bag of MI russets that were in a plastic bag (that was all that was available at the moment). In the store, under florescent lighting, they looked fine, at home in my kitchen, the entire bag was green, all over. So disappointing! One tip I have is only buy your potatoes in a paper bag and make sure the screen has been facing downward. Store lights will turn the potatoes green fast. My dad would get so upset when he noticed the potato bags upside down in the stores (we delivered our potatoes to all the local stores) and would take the time to educate every produce manager about the damage light can do to a potato. Potatoes need to breath, so putting them in a plastic bag will shorten their life, as will storing them next to onions. I always try to buy potatoes that have been grown in the state that I reside as I don’t really need a potato that has traveled 2000 miles from Idaho. The short exposure time at farm markets is nothing to worry about, most stands won’t have their produce out in direct sunlight, precisely to avoid the green potato from happening.

  35. danch

    Wow! I never thought this can be very dangerous. I am so lucky that I have read this. Whenever I cook French fries, I just ignore the green stuff, thinking it is just normal. Thank you very much for informing people about this.

  36. Eeshani

    Hi Elise,

    I’m a regular visitor to your blog, and have used several recipes (always to great effect– thank you!). I read this post awhile back, but today was the first time I ever encountered a green potato. Thank you for making me aware of the presence of solanine– probably saved me a few sick days :).

  37. Linda

    They are deadly to dogs. A couple nights ago, my friends small dog got into a trash bag which contained green parts of the potatoe which had been disgarded from that evening meal. Their dog started throwing up and it died within an hour. When cutting those parts out, put them in garbage disposal to avoid this happening to another animal.

  38. bernadette

    My husband did not hill our potatoes this year, or at least hill them enough. So we have lots and would like to know if we can use them for planting for next year?

    No idea. I would consult your local nursery. ~Elise

  39. Amy

    Thank you for the pictures. I visited several sites before yours because I was trying to find pictures.
    I read your article and most of the postings, and I still have some confusion about the peel being green and right under it. When I peeled the potatoes the green-ness went away. But is it still safe enough for children if I have peeled away all the green?
    Again, thanks for the pictures, very helpful!

    If you have a potato that has a small green spot and/or bruise, then you should peel it away. The rest of the potato should be fine. If you have a potato that has a lot of green, or very bruised, I would throw it out. ~Elise

  40. Shannon

    Years ago my husband cooked up mashed potatoes with too much green–I’d been taught to remove the green parts, but he’d been taught to eat anything that doesn’t run. I noticed a slight funny sensation on my tongue, similar to what you get from chewing a bit of tomato leaf, but decided to “not be a baby” and eat it anyway. Hah, last time for that one! I felt sick for days… Not horribly sick, just draggy, nauseous, headachy blah that went on and on. You don’t have to toss the whole potato, just peel off all of the green.

  41. m.a.

    In the past few months, I have purchased bags of potatoes from various different stores and have always found a number of bad potatoes in every bag. Usually they had black spots surrounding white moldy areas inside the potato, often up to an inch deep. Due to my frustration with the sheer volume of bad potatoes per bag, I decided to try a pricey organic bag to see if it was any better. I just brought it home and found that the potatoes were green inside. I had never seen a green potato before. Fortunately I googled “green potato” and found your site before I ate it. I’m pregnant, so I especially don’t want to be ingesting any extra toxins right now. Thanks for your informative post!

  42. Jerrine

    Hi I just wanted to know if it would still be a problem to eat the potato if it was green but you peeled it only after you boiled it. Would it make a difference from if you peeled the green part off before boiling it?

    My advice would be, if the potato just has a little green spot, cut out and discard the green part either before or after boiling. If it has lots of green, throw the whole thing out. ~Elise

  43. Jim Furr

    Hi,

    The green part is just an indication of the poison in the potato.

    Cutting out the green will not remove the poison that is throughout the potato.

    Children and the elderly are most effected. The poison last more than 24 hrs. so it is cumulative.

    Return the potatos to your grocer and get your money back.

    Jim Furr >>

  44. Jas

    G’day Elise
    We get ‘greenies’ down under too. Though it’s a rare occurrence, we’ll get the odd 1 or 2 green spuds. I either whack the green bit off or bin the entire spud if it’s green all over. Just a note…the nightshade family also includes tobacco too. Makes ya wonder a bit. And with all the fish & chips I’ve had in my life, (NOT healthy but quick & tasty), NEVER have I had a ‘greenie’ in the chip (french fry) bag.
    Thank you for what you do here.
    Cheers
    Jas

  45. Ned

    Ack! XD. I just found this site now. I should have googled green potatoes before I made my omlette last night.

    The potatoes were green inside and since the whole bag seemed like that, I thought it was normal, so I cooked it and ate it anyway.

    Over the night I had the symptoms of food poisoning and didn’t connect the dots until now. I thought maybe it was something else, until I remembered the green potatoes.

    Don’t eat green potatoes!

    I’ve taken activated charcoal to start pulling all the toxins from my system, and feel like I’m getting better today. Lesson learned there.

  46. megan

    Thanks, I always knew not to eat green potatoes, but I never knew why. The wisdom passed down from mother to child, just not why it was wise. I’ll be sure to let my children know. :)

  47. Reba Cox

    I grew some potatoes and they were not green when i dug them up. I stored them in a completely dark place and they still turned green? Do you know why?

    No idea. The green comes from chlorophyl, which only turns green when in sunlight. The potatoes can get bruised, even if stored in the dark, in which case the color will be more black-ish. ~Elise

  48. A Tenter

    Thank you for your very important and informative website on the danger of eating green potatoes..publishers should include a food safety page including this type of information…
    I first learned of this danger as I was gleaning interesting information from 92 Civil War letters of my great great Grandfather. He writes in many of his letters of the severe illness that eating very green potatoes caused, including hospitalization and extreme weakness; Recovery was slow..No doubt the storage conditions were filthy in their encampments..Things are much better now; but I see some pretty green potatoes in the bags and I just purchased a large bag of Montana potatoes from the farm; the potatoes in the center of the bag were realy green!
    Again, thank you for information that should be up front for all to see.. Encluding info on the dangers of raw red kidney beans. Keep up the good work. ATV

  49. taz

    thank you for the info.. been having stomach problems after eating some very lightly green-tinged potatoes (which i didn’t peel, cos it’s all scrubbed and clean) which tasted a bit bitter. now i know what’s the cause!

I apologize for the inconvenience, but comments are closed. You can share your thoughts on our Facebook page ~ Elise.