There is so much confusion surrounding nightshade vegetables and whether or not they are safe to eat. So we’ve decided to help you by providing the latest information on these favorite vegetables, the details of why they aren’t suitable for everyone, and how to tell if you should avoid them.
What Are Nightshade Vegetables?
Nightshades belong to the Solanaceae family of plants and include more than just vegetables. In fact, there are over 2,300 different species of nightshades, including poisonous plants as well as edible crops. The toxic, potentially deadly plants are referred to as deadly nightshades and include bushy plants like belladonna, Malabar spinach, and the beautiful Enchanter’s nightshade.
Of course, it is imperative that you avoid the deadly nightshades. But don’t worry…the nightshade vegetables we have listed below aren’t toxic or fatal to humans. They can trigger unpleasant reactions in some individuals. The symptoms nightshades can cause are similar to those produced by gluten or dairy for individuals who are intolerant of their chemical nature.
Nightshades contain psychoactive alkaloids, including nicotine, capsaicin, and solanine according to the Forest Service, a part of the United States Department of Agriculture. The psychoactive alkaloids in nightshades contain nitrogenous substances that can cause an undesirable reaction in some people, but as a whole, nightshade vegetables are considered safe for most people.
Here are the most prevalent psychoactive alkaloids that naturally occur in nightshade vegetables.
Solanine is found in both tomatoes and potatoes and can be lethal in large doses. The highest concentration of solanine occurs in green parts of the tomato and potato plant. If you just breathed a sigh of relief because you don’t eat the leaves of a potato or tomato plant—stop! Green tomatoes, as well as aging potatoes that are sprouting or turning green, contain solanine.
Nicotine is found in tobacco, eggplant, tomatoes, peppers, and potatoes. As the nightshades ripen, nicotine levels decrease. However, nicotine acts as a neurotoxin to insects, and it is used as an insecticide in some parts of the world.
Capsaicin is the heat in chiles that stimulates pain receptors when you eat a hot batch of salsa. Capsaicin extract is a powerful deterrent and is used in pepper spray and bear spray as well as topical painkillers for osteoarthritis.
What’s interesting about these alkaloids is that in some people they can cause one type of reaction while in others they can cause the opposite reaction. For example, capsaicin is often touted for its anti-inflammatory properties, which is true—but capsaicin can cause an inflammatory response in some people, especially those with an autoimmune disorder.
Who Should Avoid Nightshade Foods?
As mentioned above, the alkaloids found in nightshade vegetables can trigger inflammation and cause the immune system to respond. If you have been diagnosed with an autoimmune disease, you should avoid foods from the nightshade family.
Autoimmune diseases include:
|Hashimoto’s thyroiditis||Chagas disease||Juvenile arthritis||Vasculitis|
|Rheumatoid arthritis||Crohn’s disease||Type 1 diabetes||Multiple sclerosis|
|Lupus||Grave’s disease||Sjogren’s syndrome||Celiac disease|
|Addison’s disease||Fibromyalgia||Scleroderma||Myasthenia gravis|
|Guillain-Barre syndrome||POEMS syndrome||Psoriasis or psoriatic arthritis||Inflammatory bowel disease (IBD)|
Some people find that starting an AIP diet can help relieve inflammation and other symptoms of certain autoimmune disorders, including Hashimoto’s thyroiditis, rheumatoid arthritis, and a few others. The AIP diet, or Autoimmune Protocol, is a very strict diet that completely removes all grains, dairy, nightshade vegetables, sugar, eggs, alcohol, food additives, butter, and most oils.
Understanding Autoimmune Disease
The immune system is designed to protect the body against foreign invaders such as bacteria, viruses, and other compounds. When the immune system functions poorly, it may start attacking healthy tissue and normal cells with autoantibodies in addition to any hostile invaders that appear.
The autoantibodies attack the part of the body where the autoimmune disease is located, causing damage. For example, in individuals with Hashimoto’s disease or Grave’s disease, the body attacks the thyroid gland and keeps it from producing thyroid hormones at the right level. As thyroid diseases progress, the damage to the gland worsens, often irreparably.
There are over 80 types of autoimmune diseases, and conventional treatment, such as hormone therapy, focuses on relieving symptoms and suppressing the immune system. One of the theories of why people with autoimmune diseases have adverse reactions to nightshades is that their immune systems can’t target the alkaloids and prevent them from causing inflammation.
Symptoms You May Be Sensitive to Nightshade Vegetables
If you experience any of the following symptoms after eating nightshade vegetables, it may be wise to try an elimination diet to test your intolerance of the alkaloids.
First, remove all nightshade foods, and packaged foods where they may hide, from your diet for at least 6 weeks. Second, add a couple of servings of one particular nightshade back into your diet. Third, if any of the following symptoms occur, ask your doctor about an allergy test.
Common symptoms of nightshade sensitivity include:
- Joint pain and arthritis symptoms
- An inflammatory response
- Gastrointestinal distress including vomiting, diarrhea, bloating, or gas
- Heartburn or acid reflux
- Nerve sensitization
- Swelling in the joints
- Muscle pain
- Muscle stiffness
- Dry eyes or mouth
Health Benefits of Nightshades
Now that we’ve covered who should avoid nightshades, let’s look at the health benefits of nightshades, including their nutritional value.
- Tomatoes: Lycopene is a powerful carotenoid that may help prevent cancer and reduce inflammation, and one of the nutritional stars of the tomato. Tomatoes are also an excellent source of vitamin A and vitamin C.
- Bell peppers: Known for being an excellent source of vitamin C, vitamin B6, potassium, manganese, and vitamin K, all varieties of bell peppers also contain superpower phytochemicals such as quercetin, lutein, capsanthin, and luteolin.
- Chili peppers: Hot peppers, including cayenne pepper, are loaded with capsaicin that can relieve heartburn and spur weight loss in some healthy individuals.
- Eggplant: A staple of Italian and Chinese cuisine, eggplant is a full of dietary fiber, manganese, vitamin B6, and vitamin K. Diets high in fiber protect the heart against cardiovascular disease and high cholesterol.
- Potatoes: Red-skinned potatoes, russets, Yukon Gold, and other white-fleshed potatoes are naturally low in fat and cholesterol and are a good source of vitamin C, vitamin B6, potassium, manganese, iron, and fiber. If you eat potatoes for their fiber content, be sure to eat the skin too, as it contains over 50% of the total dietary fiber in the potato.
- Goji berries: These bright red berries are bursting with antioxidants, vitamin A, vitamin C, fiber, iron, and zinc and are believed to boost the immune system and protect against heart disease.
- Tomatillos: AKA ground cherries, contain valuable flavonoids including lutein. Tomatillos are also a good source of fiber, calcium, magnesium, phosphorus, and potassium.
- Gooseberries: Amla In Ayurvedic practice, gooseberries are known for their high concentration of vitamin C, vitamin A, polyphenols, and the flavonoids quercetin and kaempferol. Research shows that gooseberries may lower cholesterol, relieve joint pain, fight obesity, and mitigate pain and swelling after an injury.
- Okra: With an impressive nutrient profile, okra is also a good source of mucilaginous fiber—the “slime” inside the pod. Additionally, okra is loaded with powerful B vitamins, vitamin A, vitamin C, vitamin E, and vitamin K.