Beware: These Common Vegetables May Cause Inflammation

Did you know that the consumption of a certain family of vegetables called nightshades has been linked to inflammation and autoimmunity in sensitive individuals?

The Solanaceae plant family are commonly referred to as nightshades due to their tendency to grow in the shade or flower at night. There are more than 2,000 species of plants in this family but only a relative few are actually edible vegetables.

The List of common edible nightshades includes: potatoes (not sweet potatoes or yams), tomatoes, bell peppers, all spicy peppers (including spices like cayenne and paprika), and eggplant.

There are many superficial differences between all the vegetables in the nightshade family, however there are a few things all nightshades have in common; They all contain alkaloids and lectins.

For many people, moderate consumption of nightshades can be part of a healthy diet, but for others the lectin and alkaloid content of these plants can act as anti-nutrients in the body leading to inflammation, leaky gut, and autoimmunity.

That is why Dr. Colbert’s 21 Day Detox program removes nightshades to allow the digestion to reset and the immune system to balance out.


Nightshades, like all plants, contain a host of anti-nutrients to protect them from being eaten by predators such as bugs, molds, and humans. The anti-nutrients in nightshades include compounds such as lectins and alkaloids.

In small amounts these anti-nutrients can have a beneficial effect for many people by irritating the gut just enough to cause an inflammatory response that leads to a strengthening of the body. However, for those of us with sensitive immune systems or impaired digestion, the anti-nutrients irritate the gut so badly that they can lead to an exacerbation of conditions such as rheumatoid arthritis.


A class of sugar-binding proteins, lectins are found to some degree in all plants and animals. Not all lectins are harmful, but some lectins which are high in the amino acid proline resist the digestive process and can cause irritation to the gut and lead to intestinal permeability.

There are many different kinds of lectins and the specific effects of each one has not yet been studied. What is known is that lectins are a natural defense mechanism for plants and are therefore found mostly in the skin and outer edge of plants. Therefore, peeling nightshades before consumption can dramatically reduce the amount of lectins you are consuming.

But lectins aren’t the only thing to be concerned about in nightshades.


The term “alkaloid” broadly refers to any nitrogenous organic plant compound that can have a dramatic physiological effect on humans. Alkaloids commonly found in nightshades include: solanine, tomatine, capsaicin, and nicotine.


Primarily found in tomatoes, tomatine is a steroid alkaloid. This type of alkaloid is called a “glycoalkaloid” because it is attached to a sugar. Tomatine serves as an insecticide, fungicide, and anti-microbial agent for the tomato plant. It is found primarily in the stems and leaves of the tomato plant but there are detectable amounts in the tomato “fruit” itself. This alkaloid can irritate the gastrointestinal tract and affect neurotransmitter function.

Like lectins, tomatine is found primarily in the skin of tomatoes. Traditional cooking methods for tomato sauce involve removing the skins. The same is true for the solanine alkaloid in potatoes.


Solanine is a glycoalkaloid similar to tomatine. Solanine, however, is found primarily in potatoes. As the body breaks down solanine, the alkaloid is separated from the sugar leaving a compound called solanidine.

Solanadine is only toxic when consumed in high quantities, but it is known to accumulate in certain tissues of the body and be released in times of stress. The densest quantities of solanine are in the green areas of the potato plant. This is because solanine and tomatine are produced similarly to chlorophyll.

Solanine can be reduced by up to 70% by merely skinning potatoes before cooking. It is also important to remove any sprouts from a potato before cooking as these areas contain concentrated amounts of lectins.


This alkaloid is a known irritant in mammals, including humans. In fact capsaicin is famously responsible for the burning sensation associated with hot peppers. It is also responsible for many of the anti-inflammatory properties of peppers as well. Capsaicin catalyzes the release of a neuropeptide called substance P which is an important part of the network of pain signalling in the body, hence the burning sensation.


Most notably found in tobacco (another nightshade), small quantities of nicotine are also found in other nightshades such as tomatoes, potatoes, and eggplant. Nicotine is a potent neurotoxin and can be found in many insecticides. This is why the plants produce these alkaloids to begin with! As natural protection from predators, such as humans.


Many people with healthy digestive function and balanced immune systems can handle moderate nightshade consumption without ill effect. Those with autoimmune disease and leaky gut, however, must be wary.

Antinutrient activity from the lectins and alkaloids found in nightshades can irritate the intestinal lining and cause an exaggerated immune response which will aggravate autoimmune conditions such as rheumatoid arthritis.


Dr. Don Colbert found that many of his patients with autoimmune disease reacted poorly to the nightshade vegetables in most green powder formulas. That is why he formulated Divine Health’s Fermented Green Supremefood to be 100% nightshade free! Try Fermented Green Supremefood today and feel the fermented difference!




  1. Geneva Combre says:

    This very interesting on the nightshade foods. Thank you.

  2. Geneva Combre says:

    This is very interesting on the nightshade foods. Thank you.

  3. Dagmar Rendely-Martin and Al Martin says:

    any comment to this problem: my husband’s 2 fingers, middle and ring finger on the right hand became extremely sensitive, around the knuckles or a burning sensation. What kind of remedy is available. Keeps him or wakes him also in the middle of the night. He massages seems to help eases this, but it’s an answer still needed for a remedy, thanks with blessings to your Ministry, Dag and AL

  4. Carmen Walisser says:

    I purchase the Green Supreme Food and the Reds, but I have recently heard that the wheat grass in green supreme food is not healthy for us to eat. Could I have clarification of this from you. Thank you.

  5. Beverly Shaffer says:

    I appreciate your valuable health info in your articles. I have wrote notes down. I have type A Blood and sensitive a few foods. I don’t seem to do too well on too much beef. I can. eat a small portion. I fare best on natural chicken and fresh water fish like Salmon,i buy at Sprouts. I miss seeing you on TBN like Benny Hinn’s program and others. I live in Yukon,Oklahoma. I wisdh you had an office here in Oklahoma City as well.

  6. Carol Jean Friend says:

    I had hyperthyroid problems but the last year it is almost hyprothyroid with extreme fatigue.
    I stayed off dairy, un-nessecary sugars things I feel are harmful to my condition. I have been under Holliistic supervision for almost 5 years.
    I cannot lose the extra 20 lbs I have gained, regardless of how hard I try. Thinking I would have more energy if the 20 lbs would go.
    What would you suggest I do to lose the extra weight. The weight even seems to try creeping up even further. (Much tramma in my life the past two years – lost husband and also a daughter)

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