Are Nightshades Bad for You?

are nightshades bad for youIf you’ve spent any amount of time here on Mark’s Daily Apple, you know we love our vegetables. Plant foods are powerhouses of nutrients and antioxidant action. They’re the backbone of a solid Primal diet, and the main event in my signature Big Ass Salad. But the issue of nightshades has come up quite a bit over the years. Nightshade vegetables, which are vegetables that belong to the Solanaceae family of plants, include a long list of veggies and spices: eggplant, potatoes, peppers, tomatoes, tomatillos, pimentos, paprika, cayenne pepper, hot sauce, etc. (Black pepper isn’t a part of this list.)

I do eat a lot of these foods, but they’re not for everyone. In this article, we’ll dig into why some people simply can’t do nightshades, and how to tell whether you should eat them or not.


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What Are Nightshades?

Nightshade vegetables are the vegetables that grow from plants in the Solanaceae family, which Solanaceae family includes thousands of plants. Only a handful are used for food.

Nightshade Foods

Some of the more common nightshade foods include:

  • Peppers – hot, bell, sweet, etc.
  • Cape gooseberry, or ground cherry
  • Eggplant
  • Goji berry
  • Paprika
  • Pimento
  • White potato (sweet potatoes don’t count)
  • Tomato
  • Tomatillo

This is not an exhaustive list, so if you have a nightshade allergy or intolerance, consult a dietician for a comprehensive list of foods to avoid. Nicotine is a non-food consumable that is included in the nightshade category.

Nightshade Vegetables vs. Deadly Nightshade

Aren’t nightshades those plants (many with alluring little berries) our camp counselors told us never ever to go near? Let’s clear that up first.

The answer is: quite possibly. The kinds of nightshade plants growing wild in the woods can be highly toxic. Some can kill you if you ingest them. Others have psychotropic properties. Simply put, deadly nightshade is poisonous.

Inherent in this power is pharmaceutical potential. Nightshades contain alkaloids, which are chemical substances that have one or more circular structures containing nitrogen, and cause a substantial change in humans. Some natural healers may use very tiny amounts of specific nightshades therapeutically for a range of ails. Because they’re highly toxic, this is not a time for self-experimentation. You could make yourself sick, cause permanent damage to your body, or even die if you use them incorrectly. Always work with a qualified practitioner.

Why Are Nightshades Bad?

Nightshades aren’t bad for everyone. Nightshades contain alkaloids, which are harmful to some humans and innocuous to others. Whether they bother you or not depends on your epigenetics, or how nightshades interact with your genes. People who have problems with nightshades sometimes do not produce the enzymes that break them down.

Nightshade allergy or Intolerance

You can be either allergic to nightshades or intolerant to them, each of which come with different symptoms.

Nightshade Allergy Symptoms

Nightshade allergy symptoms look like the symptoms of allergies to other foods and substances:

  • Inflammation
  • Itching
  • Hives
  • Skin rashes or flare ups
  • Aches and pains
  • Nausea
  • Vomiting

Nightshade Intolerance Symptoms

The symptoms of nightshade intolerance are usually digestive in nature, including:

  • Abdominal discomfort
  • Gas
  • Bloating
  • Diarrhea
  • Indigestion, or heartburn
  • GERD
  • Nausea

But what does this mean for the tomato salad I always serve for summer barbecues? Should I give up eggplant parmigiana? No peppers or hot sauce? I thought spicy food was good for me!
Before you raid your kitchen and gardens, let’s stop and take a closer look here.

First off, nightshade foods contain a tiny fraction of the alkaloid levels found in other toxic nightshade plants. If nightshades presented a significant health threat to humans, we would’ve stopped eating them a long time ago or died off from the inability to learn from our neighbor’s experience. Even when nightshade foods are common ingredients in specific ethnic diets (peppers in parts of Latin America or tomatoes in Italy, to give some basic examples), the population as a whole in those parts doesn’t seem to suffer ill effects.

Are Nightshades Bad for You? Answer: It Depends

So, what gives? Are nightshade vegetables evil, or are they okay to eat? Our simple answer: eat them and enjoy them in moderation if you don’t feel any ill effects. Most experts accept that some people are much more sensitive to them than others. Nightshades, in those with this sensitivity, have been associated with symptoms like stomach discomfort, digestive difficulties, joint pain, and muscle tremors.

Sometimes, medical professionals will advise those with certain conditions like GERD, gout, or arthritis to avoid nightshades and see if it alleviates symptoms.

If you don’t have these conditions but are concerned, it’s a good idea to take a full 2-4 weeks off from nightshade foods and see if you feel any differently. Some of us have mild enough reactions that we may not feel the difference until we set our own “control” scenario for comparison.

Finally, if sensitivity doesn’t seem to be a problem, but you’d like to take some reasonable precautions, know that cooking nightshade foods can break down a portion of the alkaloids in nightshades. Yet another reason to avoid potatoes: sprouted potatoes and potatoes turning green have higher levels of alkaloids than they have while fresh.

The bottom line: humans are built to eat a widely varied diet. As much as we love our tomatoes, eggplants, and peppers, we wouldn’t recommend making them the sole or primary vegetables in your diet. Variety offers the best in nutrient-rich and low-risk nourishment, and it keeps things interesting.
What are your thoughts on nightshades? Do you choose to embrace or avoid them? What influences your decision?

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31 thoughts on “Are Nightshades Bad for You?”

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  1. I feel so bad for people with food allergies like this. Although it wouldn’t be the end of the world if I had to avoid these foods, it would sure make me incredibly sad. I mean, no grape tomatoes, spaghetti, chili, peppers in my curry, hot sauce, salsa, slices of homegrown tomatoes with apple cider vinegar and sprinkled with salt and pepper??
    Sorry, this is probably triggering someone who has this allergy. My bad.

  2. It certainly seems as if there is a growing movement to frame vegetables as being harmful. I appreciate Paul Mason and Paul Saladino’s research into lectins and the like, but it seems as if that information has been distorted to negate the beneficial aspects of vegetables. Mind you, I love meat, but I generally have some vegetable accompanying my main course.

    1. Thankfully, I don’t have a problem with nightshade veggies, but I know people who can’t touch them without paying a hefty price healthwise.

      Thing is, nightshades are painted with a fairly broad brush. In reality, some people can’t eat white potatoes but do just fine on heirloom tomatoes, or vice versa. Just because you can’t tolerate one nightshade doesn’t necessarily mean you have to avoid all of them. It probably depends on the alkaloid content, which can vary considerably, even from one type of potato (or tomato or pepper, etc.) to another type.

      As always, if something makes you sick or physically uncomfortable, avoid it. Don’t try to tough it out just because it’s supposed to be good for you.

    2. What are the beneficial aspects of vegetables? From a health standpoint. I get liking to have them with meat, but I think the benefits have been overestimated. What do you believe the benefits to be? Is there any research beyond associational?

    3. The question in my mind is, why eat something that’s “probably okay” and “most people can tolerate”. That could as easily apply to gluten, which most of us here probably no longer eat. The argument there is the same as with other vegetables – that even if you don’t immediately break out in hives, or have bloating or acute issues, you are probably doing small damage and working your system overtime. If vegetables aren’t needed to thrive, and they contain substances that are likely damaging (to more or lesser extent with different people), why bother? The only answer is because “I like it”, which is fine, but let’s be honest about it.

      1. There are other answers besides “I like it”.
        Some definitely argue that everyone would be better off avoiding all nightshade vegetables (not to mention other foods that contain similar alkaloids), however, we have evolved not only to tolerate a wide variety of “harmful” foods but also to benefit from them. That is one way our immune system grows resilient. Taking a reductionist approach is not always useful, especially as we don’t know what role hundreds of other alkaloids in our food play. germs, hygiene, and antibiotics come to mind as a good comparison. If we’re being honest about it, we know so little about such a complex topic.

    4. Thank you! I agree. It is ludicrous.
      Totally mainstream, thus convenient when you don’t have to think so personally for yourself and just agree what’s being told.

  3. I’ve known for years that I am allergic to eggplant, but my dislike for peppers (they never agreed with me) didn’t sync with “nightshades” until I investigated a few years ago. I seem to be OK with tomatoes and white potatoes . . . but I am going to do some experimenting and see if I do have a sensitivity. An interesting footnote: I recently experienced itching like hives except I didn’t have bumps for two days in a row. After some thought, I realized that I had eaten avocado on those days. So that’s now out for me, for the present.

  4. I have stopped eating Nightshades. They not only give me most of the allergy symptoms, they also give me insomnia. I wake up after being asleep for 3-4 hours and am awake for 2-4 hours, then can sleep another 2 hours. Not fun! I have experimented a number of times with this, since I especially like potatoes and tomatoes, but they obviously don’t like me. So I’ve given them all up.

  5. It is interesting when someone reacts to part of a family of foods, and no issue with the others. I have a horrible reaction to potatoes and eggplant. But I tolerate tomatoes, tomatillos and peppers just fine. My MD suspects my issue may be due to the higher solanine content in the white night shades. I get terrible joint pain plus substantial digestive pain and turmoil. All it takes is a bite for well over a week of pain, so I’ve diligently avoided potatoes for years. What I don’t know is if potato starch in some foods that would otherwise be safe would trigger me, so I read labels diligently and avoid anything with potato starch or unspecified starch, in addition to whole potatoes.

    Did I mention I can’t even touch potatoes with bare hands to prepare them for my family? That triggers only the joint pain in my hands, so I can wear gloves or get my people to make their own dang potatoes. Additionally, I discovered that I have relatives with the same issue.
    I initially Learned about my sensitivity from doing the Specific Carbohydrate Diet almost a decade ago.

  6. It’s such a complicated topic as there are something like 2,700 species of plants within the Solanaceae family. True that only a couple of dozen of them are mainstream foods. Our ability to metabolize them involves an assortment of enzymes and hormones, and different plants might require more of one enzyme or hormone to be properly utilized by our bodies.
    For me the solution starts with eating a variety of nutrient dense foods, and then consistently observing my body’s reaction to them. If I eat something and later feel groggy, I note that I have to identify the culprit.
    My own entire view of diet and supplementation is based on consuming what I think my body wants and needs. It’s not a constant list, but one requiring observation and modification. This is also why I prefer supplements containing an individual substance or two over some substance cocktail someone else has prepared for me. Beyond nightshades there are other foods or substances that I might not tolerate well. The adaptogen Maca, for example, makes me extremely anxious and can even induce a panic attack. So, for me it’s a substance by substance decision.
    It’s a view of life I think. My daughter-in-law asked me what foods I don’t like. I had no good response and even days later still can’t answer that question in the same way that many people would. I stopped eating what I “like” decades ago, instead choosing to like those foods that I think my body needs. For me the list would be different than for someone else. It’s not one-size-fits-all.
    I have tried a broad range of diets, including various low calorie or low fat regimens, a strict Vegan diet for six years, a raw food Vegan diet for a year, and an assortment of low carb, Paleo or Primal routines. What I have settled on is a vegetable intensive but diverse and well-formulated Ketogenic diet. I fast intermittently and try not to eat too much of any one thing. Except perhaps for green vegetables.
    I’d suggest that some who are nightshade intolerant might find that they can tolerate some on the list but not others. I have found, for example, that I have to be careful with turmeric. I’m not entirely sure why but it interferes with normal liver functions. I’m OK with some turmeric, and think some might be beneficial for other reasons, but once or twice a week is plenty for me.
    Identifying what your body does best with is a lifelong process. Nightshades are just one part of the equation.

  7. I think we can safely assume that they meant Tobacco and not Nicotine! 🙂

  8. I follow Dr. Gundry’s Plant Paradox Program (cleanse/diet) and he recommends avoiding nightshades. Plus, there are many other veggie alternatives!

    1. Dr. Gundry is a shameless huckster. His pushy internet advertising is aimed at “we’ll believe anything” internet crowd. His overly simplistic cure-all advice should be taken with a large grain of salt.

  9. Never have been able to digest bell peppers, the green variety being the worst. No way to break them down and digest them…They cause great discomfort and pain for my digestive system. My Father is the same way. I can eat other chili peppers but no bell peppers.

  10. I thought you might mention thyroid. I’ve read that if you have thyroid issues you should avoid nightshade veggies.

  11. Although I love tomatoes, I have to avoid eating them, especially raw ones as they give me the most awful mouth ulcers and on my tongue which last for about 2-3 weeks. I have been advised not to eat peppers or potatoes either after some allergy tests. Can give me the runs. I seem OK with a small about of potato starch. Most of the gluten free flour mixes contain potato starch.

  12. I learned about avoiding Nightshades and their lectins years ago while researching thyroid conditions. I am hypothyroid and have arthritis. Avoiding gluten and Nightshades have reduced the inflammation I’ve suffered considerably.

  13. Since puberty, my body had been breaking out with painful lesions. Dermatologists were always useless except to say I might have Hidradenitis Suppurativa. No one had answers about why or how to stop it. Then I developed Hypothyroidism again no real answers from doctors. I finally read a book called “The Hidden Plague” by Tara Grant. I realized it was nightshades all along. Once I cut them out it was a relief to finally understand what was going on in my body. It was also sad since I was a chef and love all food especially potatoes. It can still sometimes be difficult in social situations since most people don’t understand.

  14. I now eat way less tomatoes, potatoes and peppers. When I read about the possibility of them causing inflammation I decided to cut them out and then realized that they made up a huge portion of my diet! After cutting them out, my inflammation issues were greatly reduced. However, I have reintroduced them but in a very limited amount…maybe once or twice a week I will have one serving of one nightshade veggie…because I have a huge garden and I grow amazing heirloom tomatoes and Peruvian purple potatoes and love them! They have become a special treat! I still have occasional inflammation but mostly from old injuries…scar tissue build up…which I am working on with physical therapy.
    It’s all a very tenuous balancing act!!!!

  15. Almost no lectins and no nightshades in my diet = hsCRP .36, ESR sed rate 2, ANA no longer positive, autoimmune GONE. So yes, the effect can be quantified.

  16. Does cooking nightshades decrease the alkaloid levels at all? Rob and Diana’s book, “Sacred Cow” address a speculated Peruvian tradition of eating potatoes with a clay sauce to neutralize these alkaloid levels, but was unsure if the potatoes were cooked first?

  17. BS
    All veg is good for you. It’s the dysfunction in their systems causing this reaction / retaliation. All veggies and fruits are powerful thus they clear out the causes of chronic inflammation / etc hence it feels ‘bad’. Not the vegges fault.
    Convenient to assume it is though.

  18. Im from Denmark and I keep wondering if I have the “genes” to cope with nightshades. I mean, 99 % of all the nightshades has their origin in South America and are somewhat “new” in Europe.
    I eat some potatoes, bell peppers and eggplant, but they somehow have an off taste to me, like you Can taste and smell the bad nightshady stuff. I grow and eat my own heirloom tomatoes and that seems fine.

  19. I had perioral dermatitis for a few years and it turns out it was a nightshade allergy all along. Nightshades are also a huge trigger for my psoriasis, and they cause me digestive distress.

    Trying to go paleo has been quite frustrating, because many recipes rely so heavily on nightshades.

  20. Tomatoes actually have a lot of good effects on our health. However, the amount of organic acids in raw tomatoes is relatively large, which can cause gallbladder contractions. Therefore, people with gallstones need to consider before using it