Nightshades: Are they healthy? List + Impact on Autoimmunity

Nightshades are generally seen as healthy foods. However, a few people may be sensitive to nightshades, such as some red vegetables, fruits, and spices.

Below, we’ll discuss what makes a nightshade a nightshade, as well as a list of common nightshade foods that some people should avoid.

Are nightshade foods bad? According to a 2023 review, nightshade foods may aggravate symptoms of IBS and IBD. Autoimmune conditions may flare up when consuming nightshades. However, for many people, these are healthy foods.

It simply depends on if you’re a person who reacts poorly to nightshades. Adhering to an elimination diet is the best way to determine if your body reacts poorly to nightshades.

If you’re searching for a fresh perspective on your autoimmune health or individualized science-based dietary tips, schedule a free phone consultation with PrimeHealth. We have helped countless people treat root causes of uncommon conditions.

What are nightshades?

What are nightshade vegetables? Nightshades are foods that contain lectins and small amounts of alkaloids, which act as natural pesticides. Nightshade foods belong to the Solanaceae family of plants (in the Solanum genus).

Most people can eat them with no problem, but some become sensitive to the alkaloids. Although cases are rare, eating nightshades could even lead to autoimmunity. If you’re one of the few, it certainly doesn’t feel rare. (Check out this handy list of autoimmune conditions.)

Nightshades are mostly fruits and vegetables, but also include spices and tobacco. You may hear “nightshade vegetables” and “nightshade fruits” as separate groups, but they are essentially the same thing: foods with higher-than-typical levels of alkaloids.

Check out this list of the most common types:

• Tomatoes and tomato products (ketchup, hot sauces, soups)
• Tomatillos
• Potatoes (white potatoes, red potatoes, but not sweet potatoes or yams)
• Peppers (bell peppers, banana peppers, but not black pepper)
• Eggplant
• Sunberries
• Goji berries
• Groundcherries (not regular cherries)
• Red spices (cayenne pepper, paprika, red pepper)
• Ashwagandha
• Tobacco

Notably, you may have a potato sensitivity but not a nightshade sensitivity. Potatoes contain multiple potentially harmful proteins and chemical compounds: solanine, lectin, chaconine, patatin, and a bunch of carbs.

The belladonna plant, also known as deadly nightshade, is a member of the nightshade family of flowering plants, but it is poisonous. No one should eat deadly nightshade.

Are onions nightshades? No, onions are not nightshades. They are often mistaken for it. However, onions are high in FODMAPs, so you may want to avoid them on an IBS diet.

Zucchini and mushrooms are two other foods that are not nightshades, even though they are commonly thought to be.

Beware of hidden nightshade ingredients. Tomato and peppers are found in many foods and spices that you might not expect. Pay close attention to ingredient lists.

Why are nightshades called nightshades? Nightshade vegetables are called it, possibly because many grow in the shade and bloom in the nighttime. However, the reason is not known for sure. Truthfully, the origin of the name “nightshades” is shrouded in mystery.

Health Benefits of Nightshade Vegetables

The potential benefits of nightshade vegetables, fruits, and herbs depend on the food. Most nightshade foods are dense with nutrients, and many have anti-inflammatory properties.

Tomatoes are heart-healthy, great for your skin, and may even help prevent cancer. They are excellent sources of vitamin A, vitamin C, and the antioxidant lycopene.

Potatoes are a great source of vitamins, potassium, and fiber. “[P]otatoes contribute to antioxidant activity,” according to this 2009 scientific article.

Many peppers contain capsaicin and are anti-inflammatory. They also increase metabolism, which can help fight obesity and prevent heart disease or diabetes.

Ashwagandha is a potent adaptogen that may contribute to a healthy reproductive system and immune system.

However, for those who are sensitive to nightshade foods, the risks probably outweigh these potential benefits.

Nightshades & Autoimmune Conditions

Nightshades may contribute to autoimmune conditions, where your immune system mistakenly attacks your own body.

Many factors can weaken your immune system or confuse it into attacking your own body. Autoimmunity can take many forms.

Here are examples of common autoimmune conditions:

• Celiac disease (severe reaction to gluten)
• Psoriasis
• Alopecia
• Hashimoto’s thyroiditis
• Graves’ disease
• Type 1 diabetes
• Rheumatic fever
• Multiple sclerosis
• Lupus
• Rheumatoid arthritis
• Addison’s disease
• Sjögren’s syndrome

“Nightshades contain lectins and alkaloids, which may…increase disease activity in systemic autoimmune disease,” explains this 2019 scientific paper.

Leaky gut syndrome is a common root cause of autoimmune disease. Although the science is very young on this condition, some nutritionists and specialists posit that nightshades weaken your intestinal lining and may lead to leaky gut, which triggers autoimmunity.

Nightshades & Inflammatory Bowel Disease

Nightshades may negatively influence inflammatory bowel disease (IBD) and your digestive tract as a whole.

According to an older study, both glycoalkaloids and solanine (the defining characteristics of it) aggravate IBD, possibly even causing it in the first place. The study points out that IBD is most prevalent in nations that consume fried potatoes, such as french fries.

This 2021 study shows that adherence to an Autoimmune Protocol Diet, which eliminates nightshades among other foods, “shows promise in improvement of symptoms.”

IBD used to be considered an autoimmune disease, but recent research suggests it may not always result from autoimmunity. However, IBD can definitely weaken your immune system.

Nightshades & Arthritis

Nightshades have been associated with arthritis. Although this causation is very uncommon in reality, nightshade foods are indeed associated with autoimmunity. Rheumatoid arthritis is an autoimmune disease.

Therefore, nightshades could cause joint pain and arthritis in sensitive individuals.

Nightshades Allergy/Sensitivity

You may simply experience allergic reactions to nightshades but not autoimmunity. Children with asthma or other food allergies are at most risk of developing a nightshade allergy.

A simple nightshade allergy may cause these symptoms:

• Itchiness
• Rash
• Trouble breathing
• Nasal congestion
• Nausea

If you have a severe allergic reaction, you may need to contact your healthcare provider. If you have a lot of trouble breathing, call 911 right away.

How to Safely Consume Nightshades

To safely consume nightshades, you need to reduce the alkaloids and the lectins. I’ve separated my nightshade prep tips into alkaloid-reducing and lectin-reducing.

Nightshades contain small amounts of alkaloids, which may cause health problems if certain people consume them. Check out these ways to reduce alkaloid content in nightshade foods:

• Cook them; don’t eat them raw.
• Allow them to ripen because unripe nightshades contain more alkaloids.
• Peel potatoes before cooking and eating.

Nightshades contain lectins, which may trigger autoimmune or inflammatory reactions. To reduce lectins, you can cook or prepare nightshade foods in the following ways:

• Soaking
• Sprouting
• Fermentation
• High-pressure cooker

Nightshades Elimination Diet

If you suspect nightshades are causing you problems, and you may need to cut them out of your diet, you can follow a nightshades elimination diet and then slowly reintroduce them to your meals.

How to follow a nightshades elimination diet:

1. Eliminate temporarily all nightshade foods from your diet. Make sure you still get all your needed nutrients from non-nightshade foods.
2. Reintroduce one food at a time, giving your body enough time to react badly to each individual food. For instance, start eating banana peppers and no other nightshade on a Monday. If your body hasn’t reacted negatively by Thursday, you’re probably good to keep eating banana peppers. On Friday, reintroduce another nightshade.
3. Eliminate permanently any food from your diet once your body reacts negatively to that reintroduced food — possibly for your whole life since you now know it triggers an unhealthy reaction.

Some foods you may have suspected could end up okay to eat. Remember, simply going on the elimination diet might have given your body enough time to reset so these nightshades no longer affect you as badly.

In the end, you should know which nightshades cause you problems and which are okay for you to eat.

Substituting Nightshade Vegetables in Your Diet

You may want to substitute nightshades in your diet because you’re sensitive or because you want to be cautious. Either way, I’ve got some great tips for you to substitute nightshade vegetables, fruits, and herbs.

First of all, don’t feel like you really need to substitute these foods. Instead, try exploring new flavors. There’s no way you’ve tasted every yummy food on the planet.

That said, below are some handy substitutes for the most common nightshade foods.

Common tomato substitutes include:

• Chicken stock and vinegar
• Olive paste
• Cheese
• Cucumbers covered with non-tomato-based hot sauce
• Strawberries (especially on salads)
• Tamarind paste

I appreciated this nomato sauce recipe, which tries to capture that tomato sauce taste and mouthfeel without nightshade plants but with a lot of garlic and Italian seasoning.

Common potato substitutes include:

• Turnips
• Zucchini
• Cauliflower
• Celery root (celeriac)
• Rutabaga
• Daikon

The best non-nightshade herbs and spices include:

• Garlic
• Ginger
• Salt and pepper
• Oregano
• Cinnamon
• Cumin
• Cilantro

Do you have to give up nightshades forever?

No, you might not have to give up delicious nightshades forever. You may be able to address the root cause of your nightshade sensitivity. If you treat the underlying cause, you may be able to enjoy nightshades again.

If you’re concerned about autoimmune diseases or dietary issues, we specialize in those areas. PrimeHealth is dedicated to helping Colorado residents like you with non-invasive, as-natural-as-possible treatments on an individualized basis.

Schedule a free phone consultation with us right away. Check out our page on autoimmune diseases that we treat.

Sources

1. Kuang, R., Levinthal, D. J., Ghaffari, A. A., del Aguila de Rivers, C. R., Tansel, A., & Binion, D. G. (2023). Nightshade Vegetables: A Dietary Trigger for Worsening Inflammatory Bowel Disease and Irritable Bowel Syndrome?. Digestive Diseases and Sciences, 1-8.
2. Camire, M. E., Kubow, S., & Donnelly, D. J. (2009). Potatoes and human health. Critical reviews in food science and nutrition, 49(10), 823-840.
3. Chopan, M., & Littenberg, B. (2017). The association of hot red chili pepper consumption and mortality: A large population-based cohort study. PloS one, 12(1), e0169876.
4. Singh, N., Bhalla, M., de Jager, P., & Gilca, M. (2011). An overview on ashwagandha: a Rasayana (rejuvenator) of Ayurveda. African Journal of Traditional, Complementary and Alternative Medicines, 8(5S).
5. Wahls, T. L., Chenard, C. A., & Snetselaar, L. G. (2019). Review of two popular eating plans within the multiple sclerosis community: low saturated fat and modified Paleolithic. Nutrients, 11(2), 352.
6. Fasano A. (2012). Leaky gut and autoimmune diseases. Clinical reviews in allergy & immunology, 42(1), 71–78.
7. Patel, B., Schutte, R., Sporns, P., Doyle, J., Jewel, L., & Fedorak, R. N. (2002). Potato glycoalkaloids adversely affect intestinal permeability and aggravate inflammatory bowel disease. Inflammatory bowel diseases, 8(5), 340-346.
8. Wellens, J., Vermeire, S., & Sabino, J. (2021). Let Food Be Thy Medicine—Its Role in Crohn’s Disease. Nutrients, 13(3), 832.
9. Cuadrado, C., Hajos, G., Burbano, C., Pedrosa, M. M., Ayet, G., Muzquiz, M., … & Gelencser, E. (2002). Effect of natural fermentation on the lectin of lentils measured by immunological methods.Food and Agricultural Immunology, 14(1), 41-49.