Is there nightshade in potatoes? A Closer Look at the Solanaceae Family

November 11, 2025 •

3 min read

Yes, potatoes are part of the Solanaceae plant family, also known as nightshades. This botanical classification, while a simple fact, often sparks curiosity and concern about the safety and health implications of including this staple food in a nutrition diet.

Quick Summary

Potatoes belong to the nightshade family and contain naturally occurring glycoalkaloids, primarily solanine. In properly grown and stored potatoes, these compounds are at very low, non-toxic levels. Levels increase in green or sprouting potatoes, but are easily managed with correct preparation. Sensitivity to nightshades exists for some, potentially aggravating inflammatory conditions, but is not a universal concern.

Key Points

Potato Classification: Potatoes are scientifically classified as nightshades, belonging to the Solanaceae family, alongside tomatoes, peppers, and eggplants.
Solanine Levels: While nightshades contain glycoalkaloids like solanine, they are present in very low, non-toxic amounts in properly prepared potatoes.
Food Safety: Avoid eating potatoes that have turned green or have sprouts, as these indicate higher solanine levels. Peeling and proper storage in a cool, dark place are recommended.
Nutritional Value: For most people, potatoes are a healthy source of potassium, vitamin C, and fiber, contributing positively to a balanced diet.
Sensitivity is Individual: The claim that nightshades cause widespread inflammation is not supported by strong scientific evidence; sensitivity is highly individual and can be tested with an elimination diet.
Nightshade Alternatives: Sweet potatoes are not nightshades and make an excellent alternative for those who need to avoid the Solanaceae family.

Understanding the Nightshade Family

Nightshades are a diverse family of flowering plants (Solanaceae) that includes more than 2,000 species. This family contains a wide range of plants, from edible crops like tomatoes, peppers, and eggplants, to highly toxic plants like deadly nightshade and tobacco. Edible nightshades contain natural plant compounds called glycoalkaloids, which are bitter and act as a defense mechanism against insects and bacteria. The specific glycoalkaloid found in potatoes is called solanine.

The Role of Solanine in Potatoes

Solanine is a natural plant toxin that is present in very small, generally harmless amounts in properly stored potatoes. Higher concentrations are found in the leaves, stems, and sprouts of the potato plant, and also accumulate in the skin and green parts of the potato tuber when exposed to light. The green color is chlorophyll, which is harmless, but its presence serves as a visual indicator of increased solanine production. Consuming large quantities of high-solanine potatoes can cause gastrointestinal and neurological symptoms, but such cases are rare and easily avoidable with proper food handling.

Are Nightshades a Problem for Everyone?

For the majority of people, nightshade vegetables are a nutritious and healthy part of their diet. They are rich in vitamins, minerals, antioxidants, and fiber. However, some anecdotal evidence suggests a link between nightshade consumption and increased inflammation or aggravated symptoms in individuals with pre-existing inflammatory conditions like arthritis or inflammatory bowel disease (IBD). While some animal studies have explored this link, significant human research is lacking, and many nightshades contain powerful anti-inflammatory properties. If you suspect a sensitivity, an elimination diet under medical supervision is the recommended way to test your individual reaction.

How to Prepare and Store Potatoes Safely

Proper handling can minimize the risk of high solanine levels. Here are some key tips:

Store in a cool, dark place: Light exposure is the primary driver of solanine production in potatoes, so keep them in a pantry, cabinet, or cellar.
Remove green parts and sprouts: These areas contain the highest concentration of solanine and should be generously cut away before cooking.
Peel the potato: A significant amount of solanine is in the skin. Peeling the potato can remove 25–75% of the glycoalkaloids.
Don't reuse boiling water: If you are boiling potatoes, discard the water afterward, as some solanine can leach into it.
Be aware of taste: If a cooked potato has a bitter taste, it could indicate high solanine levels, and it should be discarded.

Potatoes vs. Sweet Potatoes

Since many people wonder about alternatives, it is useful to know that sweet potatoes are not nightshades. They belong to a different plant family, Convolvulaceae. The following table compares them based on their botanical classification and nutritional profile.


Feature	Potato	Sweet Potato
Plant Family	Solanaceae (Nightshade)	Convolvulaceae (Morning Glory)
Compound	Contains glycoalkaloids like solanine	Does not contain nightshade alkaloids
Nutrients	Good source of potassium, vitamin C, vitamin B6	Excellent source of vitamin A, rich in fiber and vitamin C
Taste Profile	Starchy and savory	Sweet and moist
Common Use	Boiled, baked, fried, mashed	Roasted, baked, mashed, pureed for desserts

Other Common Nightshade Foods

For those managing a nightshade sensitivity, it is important to be aware of other items in the Solanaceae family. These include:

Tomatoes (including tomato paste, sauces, and ketchup)
Eggplants (aubergines)
Bell peppers
Chili peppers (including jalapeños, habaneros, and spices like paprika and cayenne)
Tomatillos
Goji berries
Certain spices and condiments derived from nightshades

Conclusion: A Nutritious Choice for Most

Ultimately, the fact that potatoes are nightshades is not a reason for the average person to avoid them. When stored and prepared correctly—primarily by avoiding green or sprouted sections—they are a safe and nutritious source of vitamins, minerals, and fiber. The scare surrounding nightshades and inflammation is largely unsubstantiated by scientific research for the general population. For the small percentage of individuals who experience sensitivity, an elimination diet can help confirm the issue. For the rest, enjoying potatoes as part of a balanced diet is perfectly healthy and delicious. For a deeper scientific dive into the anti-inflammatory potential of certain nightshade components, you can explore research from the National Institutes of Health.

Authoritative Link National Institutes of Health (NIH): https://www.ncbi.nlm.nih.gov/

Frequently Asked Questions

The primary concern stems from the presence of natural compounds called glycoalkaloids, specifically solanine, which can be toxic in very high concentrations. However, properly handled and stored potatoes contain harmlessly low levels of this compound.

Yes, but you must cut away all green parts, along with any sprouts and generously peel the skin. The green indicates higher solanine content, which can be toxic. If the potato tastes bitter, it should be discarded entirely.

Scientific research has not found a conclusive link between nightshade consumption and increased inflammation for the general population. Some anecdotal reports exist, but many nightshades contain powerful anti-inflammatory antioxidants.

The most effective way to determine a nightshade sensitivity is to perform an elimination diet. You remove all nightshade foods for several weeks, track your symptoms, and then slowly reintroduce them to see if symptoms return. This should ideally be done under the guidance of a healthcare provider or dietitian.

No, sweet potatoes are not nightshades. They belong to a different plant family entirely and are a great alternative for those avoiding the Solanaceae family.

Cooking methods like boiling and baking can help reduce solanine levels, but peeling is the most effective way to remove the highest concentrations. It is still crucial to remove green parts and sprouts, as cooking does not eliminate all toxins.

Besides potatoes, other common edible nightshades include tomatoes, bell peppers, chili peppers (and derived spices like paprika), eggplants, and tomatillos.

Store potatoes in a cool, dark, and dry place, such as a pantry or cabinet, to protect them from light. Avoid storing them in the refrigerator, which can increase solanine levels.