Nightshade Vegetables: What You Need to Know

About 90 percent of us fail to meet our daily fruit and vegetable recommendations, but we turn to nightshades when we eat produce. Some of the plants in the nightshade family include tomatoes and potatoes, and these two veggies are some of the most commonly eaten produce in the U.S.^{1, 2}

Nightshade veggies are nutrient-dense and supply us with the important fiber many of us are missing out on. However, nightshades often get a bad rap because they're thought to trigger inflammation, especially in people with autoimmune conditions.

Here's everything you need to know about nightshade vegetables and whether or not they deserve a place in your diet.

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What Are Nightshade Vegetables?

Nightshade vegetables belong to the Solanaceae family, a group of flowering plants that are thought to grow at night under shaded conditions. The nightshade family consists of more than 2,000 different plants, some of which are popular food crops and others, well, not so much. Nightshade plants range from tomatoes, eggplant, and peppers to tobacco and the poisonous belladonna (also known as the "deadly nightshade").

Although they're called nightshade vegetables, many of these plants are technically fruits. Unlike veggies, fruits contain seeds, so eggplants, tomatoes, and peppers are botanically fruits, but they're often featured in savory dishes, which is why they're commonly referred to as vegetables. 

Nightshade plants are a staple in many diverse diets, but some claim that they can exacerbate certain health conditions and cause inflammation flare-ups. Most controversy around nightshades is because they contain compounds called alkaloids, specifically solanine. Alkaloids such as solanine can be poisonous in high concentrations.

Nightshades Food List

The nightshade family has over 2,000 plants, but only a few are edible. The nightshade plants that are safe to eat provide us with important nutrients, such as vitamins, fiber, and minerals that can support our overall health. But if you have an inflammatory condition or sensitivity to nightshades, you may want to avoid this produce group. 

Some edible nightshades include:

• Bell peppers
• Hot peppers (such as jalapenos and chilis)
• Eggplant
• Tomatoes
• Tomatillos
• White potatoes (not sweet potatoes) 
• Goji berries
• Spices, sauces, and condiments made with these plants include pepper, paprika, cayenne, ketchup, salsa, hot sauce, babaganoush (eggplant dip), spaghetti sauce, and more. 

<div class="pro-tip"><strong>Also Read: </strong><a href=herbs-and-spices-that-can-help-you-lose-weight>10 Herbs and Spices That Can Help You Lose Weight</a>.</div>

What Are the Benefits of Nightshade Vegetables?

Although they sometimes get a bad rap, nightshade vegetables provide us with various nutrients and can help us meet our daily produce recommendations. Eating more fruits and vegetables has been associated with health benefits, including a reduced risk for heart disease, certain cancers, diabetes, type 2 diabetes, obesity, and other chronic health conditions. That's why many dietitians recommend eating nightshade foods as a balanced diet.

Like all fruits and veggies, nightshades have many health benefits, including the following.

1. They Can Help Improve Gut Health

Nightshades are great sources of dietary fiber, arguably the most important nutrient for gut health. Eating more fiber has been shown to increase the beneficial bacteria in our gut and help prevent and relieve constipation.³

Two cups of cooked eggplant contain about 6 grams of fiber, or about 13 percent of your daily value (DV); meanwhile, one medium baked potato gives you 4 grams of fiber, or 14 percent of your DV.^{4, 5} 

2. They’re Rich in Nutrients

Like all produce, nightshades are nutrient-dense. Nightshades are great sources of fiber, vitamins A, C, E, and K, as well as antioxidants and minerals. These nutrients help support your whole-body health, including metabolism, skin, immunity, blood pressure, organ health, and more. Some veggies contain higher concentrations of certain nutrients than others, so if you'd like specific info on a certain vegetable, use the USDA search tool for a full nutritional profile.

3. They’re a Source of Antioxidants

Nightshades are rich in antioxidants. Specifically, polyphenols (plant-derived compounds), beta-carotene (a precursor to vitamin A), and vitamin E.⁶ Are also great sources of vitamin C. This antioxidant nutrient can help reduce the effects of oxidative stress. Eating a diet rich in antioxidants is linked to a lower risk of developing chronic conditions such as heart disease and certain cancers.⁷

4. They Might Help With Weight Loss and Weight Management

Nightshade plants are relatively low in calories and high in nutrients that can help support your weight-loss goals. Eggplants, tomatoes, and peppers are non-starchy vegetables that contain fiber, which keeps you full and satiated for longer and can help curb cravings. Research shows that potatoes, notoriously shunned on diet plans because they're starch-heavy, can also help with weight loss and help improve insulin resistance. 

5. They Can Support Heart Health

Nightshades are a solid source of fiber and potassium, two important nutrients for heart health. Fiber supports heart health by helping reduce cholesterol, while potassium helps lower blood pressure by relaxing the blood vessels. Keeping your cholesterol and blood pressure levels in check is key to maintaining good heart health. Nightshades can help you meet your daily fiber and potassium needs.⁹

Nightshade Vegetables: Potential Risks

Despite their nutritional value, nightshades contain compounds called alkaloids, leading some to believe these veggies have a dark side. Plants in the nightshade family contain the alkaloids solanine and chaconine, which have a bitter taste and are toxic in high concentrations. Alkaloids are mostly found in plants' leaves, stems, and unripe fruit. 

Green potatoes contain high amounts of solanine, which tastes bitter and can cause solanine poisoning when eaten in high amounts. Symptoms of solanine poisoning include fever, headaches, vomiting, diarrhea, cramps, and stomach pain. If you notice that the skin of the potatoes in your pantry has turned green, cut off the entire green part or discard the whole potato. 

Some people argue that eating nightshades can also cause inflammation and autoimmune flare-ups due to their lectin content. While lectins are associated with some health benefits, eating them in large amounts is thought to trigger inflammation and other issues. Lectins are commonly referred to as anti-nutrients because they can block the absorption of certain nutrients, namely minerals such as iron, zinc, calcium, and phosphorus. Still, these effects have only been shown in animal studies. Lectins have also been shown to activate a protein that regulates the immune system and causes inflammation, but again, this has only been observed in mouse studies.^{10, 11}

Lastly, spicy nightshades such as hot peppers contain the compound capsaicin. People who are sensitive to capsaicin may experience heartburn or stomach pain. 

Should You Avoid Nightshade Vegetables?

There isn't any human research showing that eating nightshade vegetables directly causes inflammation. However, people with certain autoimmune diseases and inflammatory conditions may want to limit their consumption of nightshade plants because they may be sensitive to the compounds in them. 

Some people with arthritis find that eating nightshades causes flare-ups in their arthritis pain. While no scientific evidence proves this, that doesn't necessarily mean it's untrue. 

If you live with rheumatoid arthritis or another autoimmune condition, consider working with a qualified healthcare professional, like a registered dietitian, who may suggest an elimination diet. Try removing nightshades from your meal plans for a few weeks, then reintroducing them back into your diet and monitoring your symptoms; if you notice your symptoms worsen, it might mean that nightshades are the culprit, and you're better off avoiding these veggies.

Suppose you've decided that nightshades don't have a place in your diet. In that case, you have plenty of other produce, including zucchini, squash, broccoli, carrots, okra, onions, mushrooms, and sweet potatoes. Although potatoes are nightshades, sweet potatoes aren't; the sweet tubers belong to the Dioscoreaceae family rather than the Solanaceae family of plants. 

The Best Ways to Eat Nightshade Vegetables

If you're concerned about the solanine in nightshades, there are certain ways to reduce your exposure to them while still enjoying the benefits these veggies offer. Here are some methods to help reduce the amount of alkaloids you take in from nightshades:

• Choose Ripe Produce: Ripe nightshades contain fewer alkaloids than unripe fruit.
• Peel the Vegetables and Remove Any Seeds: The skins and seeds of nightshade plants tend to contain the highest concentration of alkaloids. If you're concerned about these compounds, try peeling potatoes and eggplants and removing the seeds from eggplants and peppers before eating them.
• Cook Them: Instead of eating these veggies raw, try sauteing, broiling, grilling, or baking them first. Cooking nightshade vegetables can help break down their compounds and potentially make them easier to digest. 

There are many ways to eat cooked nightshades. Try the following tasty dishes and sides: 

• Eggplant parmesan
• Homemade fries or hash browns
• Ratatouille
• Chili or stew
• Babaganoush
• Homemade pizza
• Gazpacho
• Mashed potato
• Gnocchi with tomato sauce
• Shepherd's pie
• Stuffed eggplant

Also, always store your potatoes in a cool, dark place, as exposure to light can increase their solanine content and cause the skin to turn green. 

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