Are Potatoes Paleo?

Are Potatoes Paleo? | The Paleo Diet
I have noticed in the last few years that many Paleo Dieters believe that potatoes can be regularly consumed without any adverse health effects. Part of this misinformation seems to stem from writers of blogs and others who are unfamiliar with the scientific literature regarding potatoes. So should we be eating potatoes or not?

Back in the early 1980s before I had discovered Paleo, I had assumed that a low fat, high carbohydrate, plant based diet was the best nutritional plan for good health. Little did I realize how wrong I was – I should have listened to my body. One of my personal experiences at the time was how bad early morning breakfasts of boiled potatoes made me feel. They simply left me drained of energy and feeling nervous, agitated and depressed – only a few hours after my morning meal. I lived with it. But later, after poring through the medical literature, I discovered a novel idea which could explain my symptoms. In the early 1980’s a brand new concept called the glycemic index – developed by Dr. David Jenkins at the University of Toronto had just emerged. It showed us that certain food such as potatoes caused our blood sugar levels to precipitously rise and then dramatically fall. It was this effect which made me feel so bad. I ate potatoes for breakfast, and they caused my blood sugar levels to spike – only to fall drastically below their original levels shortly thereafter.

In my mind, the memory of early morning, all potato breakfasts has remained with me over the years, and I now fully understand how potatoes are one of the worst foods we can eat not only for breakfast, but as staples in our diets. As with all plant foods, sporadic consumption of potatoes will have little impact upon your overall health, but if you eat them regularly as the majority of your daily calories, your health will suffer.

High Glycemic Index Carbohydrates

In the United States we eat a lot of potatoes. The figure below shows the per capita consumption (126 lbs) of potato foods for every person in the U.S. in 2007. If we contrast this total to all refined sugars (137 lbs per capita) in the other figure below, you can see that as a country, we eat nearly as many potatoes as we do refined sugars.

So why am I bringing up this comparison between refined sugars and potatoes? Let’s take a look at the glycemic indices of various potato foods and contrast them to refined sugars, and I think you’ll get the drift.

From the values in the table below, you can clearly see that almost all potato products have glycemic indices that are substantially higher than sucrose (table sugar) or high fructose corn syrup. So, in effect, eating potatoes is a lot like eating pure sugars, but even worse, in terms of the harm these starchy tubers do to our blood sugar levels. From this information, you can clearly see why those potato breakfasts I ate so many years ago made me feel so awful. I may have just as well been consuming pure sugar or candy bars for breakfast.

Refined Sugars Potato Foods | The Paleo Diet

Because potatoes maintain one of the highest glycemic index values of any food, they cause our blood sugar levels to rapidly rise which in turn cause our blood insulin concentrations to simultaneously increase. When these two metabolic responses occur repeatedly over just the course of a week or two, we start to become insulin resistant – a condition that frequently precedes the development a series of diseases known as the Metabolic Syndrome. Over the course of months and years, insulin resistance leads to a multitude of devastating health effects. The list of Metabolic Syndrome diseases is long: obesity, type 2 diabetes, cardiovascular disease, high blood pressure, high blood cholesterol and other abnormal blood chemistries, systemic inflammation, gout, acne, acanthosis nigricans (a skin disorder), skin tags, and breast, colon and prostate cancers.

Most of the potatoes consumed in the U.S. are highly processed in the form of French fries, mashed potatoes, dehydrated potato products, and potato chips. Processed potato foods typically are made with multiple additives (salt, vegetable oils, trans fats, refined sugars, dairy products, cereal grains and preservatives) that may adversely affect our health in a variety of ways. If these nutritional shortcomings along with their high glycemic response don’t make you wary of potatoes, then the following information almost certainly will.

I have yet to touch upon the most dangerous elements of all within potatoes – antinutrients. More human fatalities and non-lethal poisonings have occurred from eating potatoes than from any other uncontaminated staple in our food supply.

Potato Antinutrients

Saponins

I can almost guarantee you that if you ask your family physician about dietary saponins in potatoes and your health; they will draw a complete blank. The same can be said for ADA trained nutritionists at your local hospital or clinic. Even astute complementary health care practitioners are usually in the dark when it comes to saponins in our daily food supply. Despite a mountain of scientific evidence showing that these compounds can be potent and even lethal toxins, they are rarely considered as dietary threats to our health.

Saponins derive their name from their ability to form “soap” like foams when mixed with water. Chemically, certain potato saponins are commonly referred to as glycoalkaloids. Their function is to protect the potato plant’s root (tuber) from microbial and insect attack. When consumed by potential predators, glycoalkaloids protect the potato because they act as a toxin. These compounds exert their toxic effects by dissolving cell membranes. When rodents and larger animals, including humans, eat glycoalkaloid containing tubers such as potatoes, these substances frequently create holes in the gut lining, thereby increasing intestinal permeability. If glycoalkaloids enter our bloodstream in sufficient concentrations, they cause hemolysis (destruction of the cell membrane) of our red blood cells.

The figure below shows how glycoalkaloids and saponins in general disrupt cell membranes leading to a leaky gut or red blood cell rupturing. These compounds first bind cholesterol molecules in cell membranes, and in the series of steps that follows, you can see how saponins cause portions of the cell membrane to buckle and eventually break free, forming a pore or a hole in the membrane.

Potatoes contain two glycoalkaloid saponins: 1) α-chaconine and α-solanine which may adversely affect intestinal permeability and aggravate inflammatory bowel diseases (ulcerative colitis, Crohn’s disease and irritable bowel syndrome). Even in healthy normal adults a meal of mashed potatoes results in the rapid appearance of both α-chaconine and α-solanine in the bloodstream. The toxicity of these two glycoalkaloids is dose dependent – meaning that the greater the concentration in the bloodstream, the greater is their toxic effect. At least 12 separate cases of human poisoning from potato consumption, involving nearly 2000 people and 30 fatalities have been recorded in the medical literature. Potato saponins can be lethally toxic once in the bloodstream in sufficient concentrations because these glycoalkaloids inhibit a key enzyme (acetyl cholinesterase) required for nerve impulse conduction. The levels of both α-chaconine and α-solanine in a variety of potato foods are listed in the table below.

Note that the highest concentrations of these toxic glycoalkaloids occur in potato skins. Fried potato skins filled with chili and topped off by sour cream and jalapeno peppers would be a real gut bomb with devastating effects upon your intestinal permeability. And literally, if you ate enough of these hors d’oeuvres, they could kill you.

So the next logical question arises: should we be eating a food that contains two known toxins which rapidly enter the bloodstream, increase intestinal permeability and potentially impair the nervous and circulatory systems?

In the opinion of Dr. Patel and co-authors: “. . . if the potato were to be introduced today as a novel food it is likely that its use would not be approved because of the presence of these toxic compounds.

In a comprehensive review of potato glycoalkaloids, Dr. Smith and colleagues voiced similar sentiments: “Available information suggest that the susceptibility of humans to glycoalkaloids poisoning is both high and very variable: oral doses in the range 1 – 5 mg/kg body weight are marginally to severely toxic to humans whereas 3 – 6 mg/kg body weight can be lethal. The narrow margin between toxicity and lethality is obviously of concern. Although serious glycoalkaloid poisoning of humans is rare, there is a widely held suspicion that mild poisoning is more prevalent than supposed.

The commonly accepted safe limit for total (α-chaconine + α-solanine) in potato foods is 200 mg/kg, a level proposed more than 70 years ago, whereas more recent evidence suggests this level should be lowered to 60 – 70 mg/kg. If you take a look at Table above you can see that many potato food products exceed this recommendation.

I believe that far more troubling than the toxicity of potato glycoalkaloids is their potential to increase intestinal permeability over the course of a lifetime, most particularly in people with diseases of chronic inflammation (cancer, autoimmune disease, cardiovascular disease and diseases of insulin resistance).  Many scientists now believe that a leaky gut may represent a nearly universal trigger for autoimmune diseases.

When the gut becomes “leaky” it is not a good thing, as the intestinal contents may then have access to the immune system which in turn becomes activated; thereby causing a chronic low level systemic inflammation known as endotoxemia. In particular, a cell wall component of gut gram negative bacteria called lipopolysaccharide (LPS) is highly inflammatory. Any LPS which gets past the gut barrier is immediately engulfed by two types of immune system cells (macrophages and dendritic cells). Once engulfed by these immune cells, LPS binds to a receptor (toll-like receptor-4) on these cells causing a cascade of effects leading to increases in blood concentrations of pro-inflammatory cytokines (localized hormones) . Two recent human studies have shown that high potato diets increase the blood inflammatory marker IL-6. Without chronic low level systemic inflammation, it is unlikely that few of the classic diseases of civilization (cancer, cardiovascular disease, autoimmune diseases and diseases of insulin resistance) would have an opportunity to take hold and inflict their fatal effects.

A final note on potatoes – to add insult to injury, this commonly consumed food is a major source of dietary lectins. On average potatoes contain 65 mg of potato lectin per kilogram. As is the case with most lectins, they have been poorly studied in humans, so we really don’t have conclusive information how potato lectin may impact human health. However, preliminary tissue studies indicate that potato lectin resists degradation by gut enzymes, bypasses the intestinal barrier and can then bind various tissues in our bodies. Potato lectins have been found to irritate the immune system and produce symptoms of food hypersensitivity in allergenic and non-allergenic patients.

Cordially,

Loren Cordain, Ph.D., Professor Emeritus

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References

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About the Author:

Loren Cordain Dr. Loren Cordain is Professor Emeritus of the Department of Health and Exercise Science at Colorado State University in Fort Collins, Colorado. His research emphasis over the past 20 years has focused upon the evolutionary and anthropological basis for diet, health and well being in modern humans. Dr. Cordain’s scientific publications have examined the nutritional characteristics of worldwide hunter-gatherer diets as well as the nutrient composition of wild plant and animal foods consumed by foraging humans. He is the world’s leading expert on Paleolithic diets and has lectured extensively on the Paleolithic nutrition worldwide. Dr. Cordain is the author of six popular bestselling books including The Real Paleo Diet Cookbook, The Paleo Diet, The Paleo Answer, and The Paleo Diet Cookbook, summarizing his research findings.

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  1. Allan says:

    Regarding potatoes, one word comes to mind…Sugar Bomb! Not only worse than processed table sugar, but…
    Plants and their immune systems have evolved to synthesize a super group of toxic compounds and proteins that play a critical role in the plants’ defense to cope with unfavorable circumstances against microbial invaders, pests and predators including humans.
    Harmful toxic compounds such as Saponins and Lectins are far too risky for humans to ingest, except in small quantities to keep the body’s immune system on its toes.
    Dietary Lectins compromise an elaborate collection of dense indigestible macro-proteins capable of recognizing, interacting and literally (enzymatically) eating right through the intestinal linings of those who would eat the plant, causing local toxic, inflammatory and infectious responses, along with penetrations of the gut wall. The penetrations of the gut wall allow the Lectins to damage DNA throughout the body through the peripheral blood.
    Lectins are resistant to cooking and digestive enzymes. They can induce dramatic dysfunctions in the precious bacterial microbiome, which in turn can cause severe diarrheal disease and food poisoning. Lectins can interfere with secretions in human airways causing chronic inflammation and infection. A variety of other diseases can be induced or promoted by lectins. Some are: celiac disease, peptic ulcer, IgA, nephropathy, insulin resistance and diabetes, rheumatoid arthritis, etc.
    It is beyond comprehension why any reasonable person would subject their bodies to such risk and harm.
    However, (with genetics aside)* the body’s immune system is such an amazing and wondrous gift that, when healthy, can usually neutralize harmful compounds in small quantities. In fact, it actually needs to be exposed to challenges in order to keep its responses ready and alert. Lections are becoming a valuable asset in scientific research.
    It seems logically and scientifically valid that even strict Paleo diets should include small quantities of cereal grains (other than corn, soy and potatoes), as along as they are whole and unprocessed (Chocolate Chip Cookies and wild rice, both of which are borderline paleo,[see post about chocolate chip cookies])
    *Genetics seems to be the most complicated of sciences. Even though we have learned more about genetics in the last few years than was ever known in all of human history, the science is still in its infancy and valuable therapies and interventions seem distant.
    However, that may be about to change in extraordinary and profound ways in the near future. (more on that later)

    Acknowledgements:

    See generally: Dr. Andrew Weil, BA,MD Harvard),Prof Univ.Az. “Why Our Health Matters(2009, “Spontaneous Healing”(1995), Healthy Ageing”(2005)

    Phytochemistry, 2015 Jun 5;117:51-64 doi10.1016/j.phytochem.

    Dang L, VanDamme EJ, Toxic Proteins in Plants; Front Plant Sci.
    2014;5:397 PMCID:PMC43131498

    Nausicaa Lannoo, EJ Van Damme, Lectin Domains at the Frontiers of Plant Defense Front Plant Sci…

    Sharon N, Lis H Lectins Cambridge, UK; University Press

    Wang Q, et al. Identification of Intact Peanut Lectins in Peripheral Blood; Lancet. 1998; 352: 1831-1833 (Pub Med)

    Freed DL, Lectins Br. Med J (Clin. Res.) 1999, 1985, 280l 584 (Pub Med)

    Banwell JG et al. Phytohemmagglutinin-induced diarrheal disease; Dig. Dis. Sci. 1984;29:921-929

    European journal of clinical Nutrition, 10/1993; vol. 47, iss 10 (anay)

    Cordain L. Toohgey L. Smith M etal. Modulation of Immune Function by Dietary Lectins in Rheumatoid Arthritis; Br. J Nutrition 03-2000 Vol 83 iss 3

    See generally Gary E. Marchant BSc,MPP,PHD,JD, Prof.of Genetics and the Law, Sandra Day O’Connor College of Law, Arizona Stat University

  2. Alfie Mueeth says:

    First off, let me say that I owe ALL my weight loss and self confidence due to the Paleo diet. I started about a year ago and at first I was a purist, cut out potatoes etc. Now I am a bit more relaxed and guess what, I haven’t ballooned into a hideous creature.

    I have to agree with broncho, have a few cheat meals here and there, trust me, you will be fine.

    Great article sir!

  3. Broncho says:

    Most paleo dietitians now a days follow a 85:15 ratio, i.e 85% of time follow paleo diet strictly. That is almost 2-3 cheat meals.
    This diet falls short on is some of the micronutrients, namely calcium and vitamin D because dairy products (good sources of the said micronutrients) are off-limits
    So what I do is add the essential nutrients in my diet during the cheat days.

  4. Pat says:

    I believe it. I have suffered from anxiety for 10 years. Started after my father passed away. A couple of years ago a chiropractor told me to stop eating Patatoes, because of back and joint pain, along with low grade inflamation and anxiety. Took me 6 months to finally give it up, not believing it. Gave it up for a year along with wheat. What a difference, I felt like a new man. And lost 20 lbs. no anxiety and very little pain. Fast forward to today. After 6 months of no exercise and Patatoes and bread. Ended up in ER with afib. Anxiety and severe back pain. Doctors put me on pills for heart beat regulation and an aspirin a day. Now I have to start all over with the detox. I learned my lesson now.

    • Rose says:

      Could be the wheat and not the potatoes. You can’t really stop 2 things and then blame both when you feel better. This is not conclusive at all.

  5. Dan says:

    Will the negative effects still outweigh the positive effect if I were to eat only 2 T of unmodified resistant starch? Of which 80% is indigestible?

  6. james says:

    What about the difference between sweet potatoes and yams?

  7. AK says:

    I ate 1 baked Idaho potato everyday and experienced the spikes you mentioned above. I also experienced painful bowel movements and ankle/foot pains. But I continued to eat potato daily due to the fiber and potassium. I have since stopped and no more pains. Thanks for the article.

  8. Matt Konig says:

    Wow nothing like an extremely well researched, well written article to reinforce the clear health benefits and costs of certain foods.

  9. Sinder says:

    The paleo diet is not just about avoiding gluten its also about avoiding carbs. You can still eat patatoes but keep it in moderation. Thats what ive been doing and ive been feeling 100% every day. Hope this helps.

  10. Natalya says:

    Fascinating article. Found the glycoalkaloids information really intriguing.

    Can it be said that freezing potatoes reduces the amount of glycoalkaloids?

    Like some of the other commenters, I too was curious as to whether sweet potatoes also contained harmful saponins, but was relieved to discover that they are from an entirely different family and make a great alternative.

    Thanks for such an informative post.

  11. Aria says:

    What about Purple Potatoes? They are suppose to have antioxidants in them but are they bad to have with dinner every night? Same questions goes for sweet potatoes. Thank you for the help!

  12. Batziona says:

    Dear Loren, I think you might want to revamp this article. While I appreciate the science you present, there is one element you completely overlook: the huge differences in human bodies. Without going into massive detail, since I am highly allergic to inulin and lignin, my ability to digest most vegetables approaches zero. Potatoes, on the other hand, are truly my life saver. I have been dealing with this problem ever since 8 years old, and I am now 58, so I know of what I speak. In fact, it is hereditary in our family and no amount of gut and diet tweaking fixes the problem. All the tricks in the book – making my own yogurt and eating organic and so forth – help, but don’t solve the issue. If not for potatoes, I would be ravenous every day. So, the science is cool as long as the conclusions reached are taken with 20 grains of salt. It is never, ever good to propose across-the-board conclusions. People need to listen to their bodies, track what they eat, track their reactions, and then reach their own informed conclusions. Thank you.

  13. David says:

    Hi!

    This might not be a 100% fit but since you mention Ulcerative Colitis (UC) as one of the issues that can be caused by glycoalkaloid saponins, maybe it does interest (and especially help!) some people here:

    While I am a big believer in Paleo as the only nutrition concept that makes sense, I know that when it comes to fighting illnesses such as UC we sometimes have to rely also on meds. My fiancée suffered for exactly 10 years from UC. Those years were plain torture, not only for her but also for the people that are close to her, i.e. me too.

    Recently, totally out for the blue, we found what seems to be a solution for UC. I decided to write down our story, hoping to help others. To help more people I also paid money to have it translated a couple of other languages, incl. into English. I hope the Paleo Diet Team will let me use this opportunity here to share the experience, hoping it can help some others suffering from UC as well. Of course, there’s also reference to Paleo inside.

    http://stop-ulcerative-colitis.com/en/

    If you like it, please share with your friends etc who might be on the same difficult journey and for whom this could be a solution as well.

    Thank you and best regards from Greece,
    David

  14. Joe Gomez says:

    I agree with only one thing, that is that we need to maintain a regular diet in what ever we consume, it is true that consuming potatoes or any product for that matter in excess with damage your digestive system one way or another, come on people it’s all about common sense! the true reason of potatoes and the paleo diet is because potatoes are extremely processed! Like I said is all about common sense! Potatoes are processed in the extreme by manufacturers all over the world, the demand for them is beyond limits, farmers as producers they need to have enough to satisfy that demand and the only way to do so is by modifying their crops to produce bigger and faster products, the problem is that this modification involves chemical alterations to them and when you eat that “potato n question” well? You’rte eating everything that come with it! simple as that! As for the glycemic part? Well your body needs sugars natural sugars not processed! so potatoes would be a source, but again all in moderation! Remember that the word “Paleo” is short for paleolithic, meaning the period of time when caveman roam the earth, their diet was NOT the best! this is why their train of though, or better said they brain capabilities to deduce a situation was not the best! We aquired this with a think called Evolution! lol.
    Plus as stated how in the world would a “caveman” know where a potato, sweet potato, carrot, or anything buried would be? Cavemen were more gatherers “you see, you pick, you taste and if is good you eat! lol when it came to moving food! “hunting” if there was people to help they would do it otherwise, any caveman would chose an apple a million times rather than chasing something all day! Bottom line, have a balanced diet and avoid processed foods and products!

  15. Chris Foley MD says:

    Saponins are not all bad. The vilification of potatoes because they have saponins is disingenuous at best, and at worst, signifies a little pharmacognostic ignorance here that is surprising. Licorice root, ginseng, and ashwaghanda all are rich in particular saponins, and it is these components that are thought to render the. Very valuable to human health. So to say potatoes are bad because of their saponin content is just plain ignorant. C’mon, Laurin.

    • Jonathan Bojan says:

      I don’t think that’s what this article is saying. I think he’s pretty clear that it’s potato saponins in particular that are the problem. He’s referencing specific compounds that can be cross checked apart from the body of saponins as a whole. The saponins in other plants haven’t even come into question in this article, so I’m wondering why you are bringing them up as a reason to bash the article? It seems you’re accusing him of lumping saponins together when that’s actually what you’re doing.

  16. Christina says:

    I still don’t quite understand why not ALL nightshades are excluded from Paleo.

    • I believe that in Loren Cordain’s book: The Paleo Answer, he wrote that all the nightshade family has anti-nutrients in them. In the case of tomatoes, the detrimental effect is less in some varieties and according to the level of ripeness.
      Different writers include different items. Some recommend using cooked tomato products but the originator of the Paleo diet doesn’t recommend it.

  17. Akiva says:

    For the chart above, what amounts of potatoes equal the amount of a-chaconine + a-salonine? For example how much potatoe skins equal the amount 567-1450 mg/kg a-chaconine + a-salonine? Please specify for each form of potatoe. Also I don’t understand, is the a-chaconine + a-salonine measured in mg or kg?

    • Steve says:

      There is the rub! The way the table reads, implies, is that “567-1450 mg/kg” means that in 1 kilogram of potato skins, you will find 567-1450 milligrams of alpha-chaconine + alpha-salonine. BUT, in his 5th paragraph from the end, he refers to “doses in the range 1 – 5 mg/kg body weight,” which is a completely different measure.

      The swapping of mg/kg of the foodstuff with mg/kg of body weight is amateurish.

      • Don says:

        You seem to be mistaken in your comment. The listing of mg/kg content of salonine in a given potato preparation does in no way contradict the value that might be harmful to the human body. In fact – NOT knowing how much there is in a given value of potato, there is no way of comparing how a given wt of potato and their respective solanine content might affect the body.
        Take time to understand – you will save time in making incorrect response…

        • EJ says:

          I agree with the first poster, the article does state “oral doses in the range 1 – 5 mg/kg body weight are marginally to severely toxic to humans whereas 3 – 6 mg/kg body weight can be lethal.” This statement makes me question the table. The paragraph preceeding the table talks about the concentration in blood and the levels considered to be “toxic,” making me further question the MG/KG.

          • bob says:

            Maybe it’s milligrams PER kilogram of body weight as would be expressed in mathematics… doesn’t seem confusing to me but I did pass the 6th grade. Also the oral and digestive absorption rate is not 100% so the discussion of toxic oral ingested quantity VS lethal blood level is understandable in that light. And as further explained in his book the margin between what is toxic and what is potentially lethal is disturbingly narrow. So there could be overlap in levels depending on the individual.

    • Donna says:

      Yes I initially paused at this (use of mg/kg in the foodstuffs in the table, then mg/kg bodyweight in the text) – but on rereading he is talking about different studies and recommendations, and therefore referencing different measures – it is not confusing if you read it carefully.

  18. Kevin says:

    Before i begin please do not get me wrong, i am starting the Paleo diet myself, and believe that the results of others speak for themselves. I am confused with what people define “Paleo Diet” as and perhaps someone could shed light on this. If we define it as those foods which were available and consumed by our paleolithic ancestors, how can we then separate some foods out of that list such as regular potatoes vs sweet potatoes. Both were available to ancestors, and both were consumed. Both are the same family (Tuber). The only difference i can see is the modern techniques available to determine the nutritional value (or presence of unhealthy components) within the specific foods. Are we applying modern investigative processes to evaluate what our ancestors “should” have eaten in order to come up with our definition for “Paleo”? I am new to this so my apologies if it appears argumentative. I thought that “anything they ate” was an apt definition of this plan, but the online resources i have discovered are telling me differently. Thoughts???

    • Chris Foley MD says:

      Kevin….you are spot on. Most if not all of Dr Cordain’s references are for in Vito studies that hardly reproduce the in vivo environment of the human gut. There is not one shred of clinical in vivo evidence that a routine meal of potatoes in the usual serving size would cause a clinically significant level of intestinal permeability. Not one study. I am a Paleo advocate, and I have known Dr Cordain for quite a while. Modest use of potatoes as a carb source will NOT cause issues. Gluten is another matter.

      • Hi,

        I have known Chris for many years and like and respect him. Here are the in-vivo human and animal studies (both from direct references and review papers) involving potatoes and gut permeability/and health which Chris apparently has not read.

        De Swert LF, Cadot P, Ceuppens JL. Diagnosis and natural course of allergy to cooked potatoes in children. Allergy. 2007 Jul;62(7):750-7.

        El-Tawil AM. Prevalence of inflammatory bowel diseases in the Western Nations: high consumption of potatoes may be contributing. Int J Colorectal Dis. 2008 Oct;23(10):1017-8.

        Francis G, Kerem Z, Makkar HP, Becker K. The biological action of saponins in animal systems: a review. Br J Nutr. 2002 Dec;88(6):587-605.

        Friedman M. Potato glycoalkaloids and metabolites: roles in the plant and in the diet.J Agric Food Chem. 2006 Nov 15;54(23):8655-81.

        Hellenäs KE, Nyman A, Slanina P, Lööf L, Gabrielsson J. Determination of potato glycoalkaloids and their aglycone in blood serum by high-performance liquid chromatography. Application to pharmacokinetic studies in humans. J Chromatogr. 1992 Jan 3;573(1):69-78.

        Higashihara M, Ozaki Y, Ohashi T, Kume S. Interaction of Solanum tuberosum agglutinin with human platelets. Biochem Biophys Res Commun. 1984 May 31;121(1):27-33.

        Iablokov V, Sydora BC, Foshaug R, Meddings J, Driedger D, Churchill T, Fedorak RN.Naturally occurring glycoalkaloids in potatoes aggravate intestinal inflammation in two mouse models of inflammatory bowel disease. Dig Dis Sci. 2010 Nov;55(11):3078-85.

        Keukens EA, de Vrije T, van den Boom C, de Waard P, Plasman HH, Thiel F, Chupin V, Jongen WM, de Kruijff B. Molecular basis of glycoalkaloid induced membrane disruption. Biochim Biophys Acta. 1995 Dec 13;1240(2):216-28.

        Keukens EA, de Vrije T, Jansen LA, de Boer H, Janssen M, de Kroon AI, Jongen WM, de Kruijff B. Glycoalkaloids selectively permeabilize cholesterol containing biomembranes. Biochim Biophys Acta. 1996 Mar 13;1279(2):243-50.

        Mensinga TT, Sips AJ, Rompelberg CJ, van Twillert K, Meulenbelt J, van den Top HJ, van Egmond HP. Potato glycoalkaloids and adverse effects in humans: an ascending dose study. Regul Toxicol Pharmacol. 2005 Feb;41(1):66-72.

        Morris SC, Lee TH. The toxicity and teratogenicity of Solanaceae glycoalkaloids, particularly those of the potato (Solanum tuberosum): a review. Food Technol, Aust. 1984;36:118-124.

        Morrow-Brown H. Clinical experience with allergy and intolerance to potato (Solanum tuberosum). Immunol Allergy Practice 1993;15:41-47

        Naruszewicz M, Zapolska-Downar D, Kośmider A, Nowicka G, Kozłowska-Wojciechowska M, Vikström AS, Törnqvist M. Chronic intake of potato chips in humans increases the production of reactive oxygen radicals by leukocytes and increases plasma C-reactive protein: a pilot study. Am J Clin Nutr. 2009 Mar;89(3):773-7

        Patel B, Schutte R, Sporns P, Doyle J, Jewel L, Fedorak RN.Potato glycoalkaloids adversely affect intestinal permeability and aggravate inflammatory bowel disease. Inflamm Bowel Dis. 2002 Sep;8(5):340-6.

        Pramod SN, Venkatesh YP, Mahesh PA. Potato lectin activates basophils and mast cells of atopic subjects by its interaction with core chitobiose of cell-bound non-specific immunoglobulin E. Clin Exp Immunol. 2007 Jun;148(3):391-401.

        Smith DB, Roddick JG, Jones JL. Potato glycoalkaloids: some unanswered questions. Trends Food Sci Technol 1996;7:126-131.

        Ryan, C.A. and G.M.Hass, Structural, evolutionary and nutritional properties of proteinase inhibitors from potatoes. 1981. In : Ory, R.L. (ed.), Antinutrients and natural toxicants in foods. Food and Nutrition Press Inc., Westport ,CT.

  19. Megan says:

    I found this on a Q&A page from January 2012 (http://thepaleodiet.com/paleo-diet-q-a-6-january-2010/)

    Q: Are baked sweet potatoes allowed? I thought not!

    A: Yes, sweet potatoes are allowed, specially in the post-workout period if you are an athlete. Sweet potatoes are different from potatoes in that they do not contain several harmful substances such as saponins and lectins, which may increase your intestinal permeability (if consumed regularly) and rev-up your immune system. But on the other hand, sweet potatoes are high glycemic index foods and should be restricted if you are struggling with overweight, at least until your body weight normalizes.

  20. Nora says:

    Yes, I have been eating resistant potato starch for the last few months, based on recommendations from more than a few paleo proponents. Please tell me what you think about this.

  21. Adrienne says:

    I hope Dr. Cordain will address the issue of resistant starch which is one of the reasons some paleos are advocating eating substances with decent amounts of resistant starch such as: raw potato starch; green bananas; cooked and cooled rice and legumes; seeds such as cashews and nuts such as pistachios.

  22. Diana says:

    I agree with Megan. If we’re talking about potatoes, lets include all the potatoes! Sweet potatoes are not high glycemic.

  23. Donna says:

    I have always understood that fresh, new potatoes (from the ground, not the can) were lower on the glycemic index scale, that the more mature the potato, the higher the GI. Is this not true?

  24. Megan says:

    What about sweet potatoes?

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