Nightshades are some of the most commonly used plants, easily found in every market.

Paprika, potato, eggplant – these vegetables all belong to the nightshade family.

This also includes peppers in all their varieties, as well as tomatoes.

Nightshades are used for food all over the world, but as time passed and new knowledge about them emerged, people started wondering if nightshades are truly as good for our health.

These plants, although usually completely harmless to most of the people, can cause some serious issues when if you’re suffering from an autoimmune decease, or simply have a very sensitive stomach.

Let us see what exactly nightshades are, find out how they work when eaten, and see whether or not we should limit the consumption of nightshades or completely stay away from them.


Nightshades are the plants belonging to the Solanaceae family, which contains more than 2000 species.

White potato, eggplants, peppers (both their chili and sweet bell varieties) – all of these are numbered among the nightshades.

Red pepper flakes, cayenne pepper, paprika, and other spices derived from peppers also fall into this category, the exception being the black pepper since it belongs to a completely different family of plants.

The aforementioned nightshade plants, including tomatillos and goji berries, are edible (and quite delicious too!), while another member of this family, although able to bear fruits, is not an edible plant, so we use it for its leaf instead.

That plant is as widely known as it is wide-spread, and its name is – tobacco.

Tobacco is probably the most obvious example of nightshades’ detrimental effects to our health, but more on that will be said later in the text.


As extensive as this family of plants may be, the list of the edible nightshades is, sadly, not overly long, but the number of nightshade plants with highly toxic properties is impressively large.

Most of the poisonous nightshades are very dangerous for humans, and they’ve been traditionally valued for exactly this feature.

The most famous of the poisonous nightshade is probably the belladonna, commonly known as “the deadly nightshade”.

Belladonna was highly regarded for its brutal efficiency, and it is further immortalized by the great William Shakespeare in one of his greatest plays – Macbeth.

The name belladonna means “beautiful woman” in English, and it is probably connected to the alternative use of this plant. Women once used the belladonna extract in order to cause the dilation of their pupils, and thus be more attractive to men.

Because of the long list of poisonous nightshade, there are people who show great levels of concern when it comes to all nightshades in general.

Since belladonna is so poisonous, how can potato or tomato be good for us?

Traditionally, gardeners expressed their doubts regarding the actual nutritional values of nightshades, so they grew them simply because of their beauty.

Their belief, combined with the growing distrust towards nightshades has some sense, but the truth is this: edible nightshades pose absolutely not a threat for us.

If, of course, we’re already perfectly healthy.

On the other hand, if you’re suffering from chronic deceases, autoimmune deceases, have sensitivity towards certain types of food, allergies, leaky gut syndrome or inflammatory bowel decease, eating nightshade vegetables may prove as a very, very bad idea.


One of the causes of possible health risks related to consuming nightshades in your everyday diet is their negative influence on joint pain and arthritis, especially rheumatoid arthritis.

This case is presented by N. F. Childers, P.h.D. and M. S. Margoles, M.D. However, this “proof” cannot be considered completely reliable due to it being based upon conversations with various people regarding their diet and whether or not they experienced the negative effects of the nightshades, however helpful their idea of eliminating nightshades from their interlocutors’ diets proved to be.

One of the potential causes of people with chronic illnesses’ negative reaction to consuming nightshades may have something to do with Vitamin D.

Evidence gathered from animals showed that the joint problems and bone issues the animals have been experiencing are all due to the way their bodies process the Vitamin D derived from nightshade consumption.

Vitamin D is of great importance when it comes to the overall health of bones.

However, the D3 variant of Vitamin D is proven to have negative effects – it actually causes disturbances in calcium metabolism.

Consequently, the improperly processed calcium is deposited in the soft body tissue instead of within the bones.

This is the reason why animals suffer from severe joint inflammation.

However, we humans do not process Vitamin D in the same manners that animals do.

Substances which have a negative influence on animals have no effect on humans, and vice versa, so the offered evidence, however important, does not exactly prove that these issues will affect us in the same manner, if at all.


There are, on the other hand, researches which attribute the negative influence of the nightshades to our organism to the substances naturally found within the said plants.

These substances are called lectins and alkaloids (or glycoalkaloids).

1. Lectins

Lectins are proteins bound to carbon-hydrate, i.e. sugar.

These macromolecules are of great importance since they’re able to recognize specific cells and molecules within our body and play the role of mediators when it comes to the process of binding between the bacteria and viruses and their respective targets.

Lectins can be found in basically every food source, to the greater or lesser extent.

Some foods, such as beans and grains, must be either fermented or cooked in order to reduce the lectine percentage.

Some of them, such as CLEC11A lectine, actually has some beneficial effects. Other lactines, such as ricine, act as toxins and can be extremely dangerous.

It is not easy to easily distinguish between the beneficial, or at least harmless, and the dangerous types of lectins because of them being so widespread in almost every source of food.

We know for certain that the lectins in peanuts are harmful to humans since they act as a bowel irritant and cause the “leaky gut syndrome”, which is also something alkaloids do as well.

2. Alkaloids

Alkaloids are chemical compounds, naturally occurring and organic in nature, usually consisted of basic nitrogen atoms.

They are produced by plants, animals, fungi, and animals.

Alkaloids within nightshades are also known as glycoalkaloids, and they are, essentially, the plant’s defense mechanism, a naturally occurring pesticide.

Even though they exist in every part of the plant, those parts of the plants with the highest level of glycoalkaloids are unripe fruit, flowers, and leaves.

Glycoalkaloids work in two ways.

When a predator eats a glycoalkaloid-rich unripe fruit, the compound bounds with cholesterol cells of the predator, that way eroding their membrane and causing them to leak or break.

The other way is through interaction with an enzyme called cholinesterase.

This enzyme reacts with a neurotransmitter called acetylcholine, which leads to overstimulation of the muscular tissue, and consequently, paralysis of the predator.

Essentially, glycoalkaloids, at least context, are acting as neurotoxins.

Alkaloids found within nightshades include, but are not limited to, the following:


When solanine enters the body once we eat nightshade which the highest concentration of this alkaloid, the bond with sugar is severed due to our bodies metabolizing of this alkaloid, so only solanidine is left.

Solanidine is not toxic in small amounts we enter in ourselves while eating, but it tends to accumulate over time and starts damaging our body when we’re under great stress.

This steroid alkaloid is found in potatoes, and its counterpart, located within tomatoes, is called tomatine.

Solanine and tomatine are produced in very much the same way the plants produce chlorophyll.

This essentially means that the highest concentration of these alkaloids, as we have already mentioned earlier in the text, can be found in the greenest parts of the plant.

It is true that we mostly never eat those parts, but take care: every patch of green on not-quite-ripe fruit can potentially have a high concentration of solanine/tomatine.

The detrimental effects of this steroidal alkaloids include irritation of the digestion system, and can also cause disturbances within the neurotransmitters.

Documented cases of solanine poisoning exist, although they are very rare, and they include central nervous system depression, vomiting, diarrhea, and in some extreme cases, death.


As we have already said, nicotine is an alkaloid found within the tobacco, which is also a type of nightshade.

It is widely known that this alkaloid is the reason why tobacco is so addictive, and why so many people worldwide smoke cigarettes and cigars in large amounts, but other than addiction, it causes breathing difficulties and lung cancer, among other things.

Bear in mind: the fact you’re not a smoker and that you actively avoid places where smokers gather does not mean that you’ve successfully avoided nicotine!

Nicotine can be found in basically every type of nightshade, in a greater or lesser extent.

Which probably explains why we get so easily hooked on French fries!


Capsaicin is the alkaloid found within peppers. Although it has some anti-inflammatory characteristics, it can cause a lot of trouble aside from the well-known taste of peppers.

If you ever felt like your very soul is on fire after eating a particularly hot habanero or a salsa, its capsaicin’s fault!

A side-effect of capsaicin burning your taste buds is the release of a compound called Substance P.

When that happens, there comes of period where your sense of taste (and all the pain receptors within your mouth) feels like its deadened, so the searing heat you felt at the first bite is significantly weaker at the fourth and the fifth bite.

That’s why this alkaloid has some use as an analgesic, especially when it comes to treating osteoarthritis.


When it comes to overall direct danger to humans, we don’t really have anything to worry about.

The concentration of alkaloids in edible nightshades is small, and since most of it, as we have already said, is concentrated in the parts we don’t actually eat.

Even if we did, it would take a high concentration of alkaloids to actually harm us, and such amount is found in poisonous nightshades.

But just like we said, a person with a perfectly healthy body can deal with these substances without much of a trouble.

People with certain health issues, like the ones we mentioned above, are not that lucky.

In case you’re suffering from an autoimmune disorder, alkaloids you’ve consumed may lead to a stronger immune reaction, which is something which must be avoided.

One of the problems the alkaloids can cause within the body of a person troubled by an autoimmune disorder is the gut inflammation.

Since it’s their nature to act as a pesticide, and since the pesticide is a toxin made to, essentially, kill any and all pests that potentially harm the plant, alkaloids attack the cells within your digestive tract, causing “leaky gut”.

The protein from the cells within the digestive tract, instead of remaining where they’re supposed to be, end up in our bloodstream, which kick-starting a potent autoimmune reaction – our body attacks them seeing them as foreign bodies and potential threat.

Other research shows that glycoalkaloids can destroy even the cellular membranes of our blood cells and mitochondria!


To reiterate: nightshades are harmful only to those sensitive to them for reasons we have explained earlier.

If you’re a healthy individual not suffering from any form of autoimmune deceases, you’ll be perfectly fine.

In fact, some of those substances within the nightshades which cause such a detrimental effect when consumed by people with sensitive digestive tract can be actually beneficial to those that don’t.

1. Anti-inflammatory Properties

For people with the healthy digestive system, capsaicin, the alkaloid found within peppers is actually used to counter bowel inflammation, and it is one of the beneficial factors of eating peppers!

However, within the body of someone with more sensitive bowels, it has a completely opposite effect.

The moment capsaicin appears in the digestive tract of a healthy person, their body reacts with a powerful anti-inflammatory response.

That way, capsaicin serves as sort of a catalyst for positive chemical reaction within our bodies.

The reason for such a reaction may lie in the fact that glycoalkaloids – capsaicin being among them – have a similar structure to that of glucocorticoids.

Glucocorticoids are special compounds known for their strong anti-inflammatory features, the most famous of them being prednisone and cortisol (this one is actually the stress hormone of our body).

However, it must be noted that excessive amounts of these substances just because they have this one beneficial feature.

Too much prednisone causes some pretty nasty side-effects, and too much cortisol slows down your metabolism and undermines the efficiency of our immune system.

2. Anti-Bacterial Properties

Nightshades can be of great help when it comes to fighting bacteria and viruses.

Laboratory experiments have shown that alkaloids and lectins found within nightshades possess strong anti-bacterial properties.

This is discovery is perfectly in accordance with their nature: they are meant to help the plant fight aggressors both from within and from without.

3. Anti-Cancer Properties

While conducting researches with the purpose of finding every possible way of fighting and destroying cancer cells, scientists tried using nightshades, i.e. alkaloids and lectins extracted from them.

In vitro experiments have shown that alkaloids can actually cause the decline of cancer concentration by “making” them self-destruct.

The reason why this is not a widely spread method of fighting cancer is due to the fact that alkaloids and lectins used in this purpose often trigger the self-destruction healthy cells as well, which makes them a real double-edged sword.

Consequently, in vivo trials on animals and humans have not been conducted, and it shall remain so until ways of countering these side-effects are discovered.


Everyday recipes are full of nightshades, but don’t worry: if your body can’t deal with them, there are great (and very tasty) substitutions out there.

By using them, you won’t be forced to give up preparing and enjoying your favorite meals, and they’ll be equally tasty and significantly healthier for you!

1. Potatoes

Potatoes, as we’ve said above, are rich with alkaloids, so they don’t agree with some people that well. Luckily, there are more than decent substitutions for them.

Sweet potatoes, for example, are not only a delicious vegetable, but they are also completely alkaloid-free, thus not causing any of the usual nightshade-induced issues. You can use them for basically any meal common potatoes are used for, and with no side-effects whatsoever.

Jicama, nicknamed “the Mexican potato”, is another effective substitution, though not so commonly known. Not only it is great for making French fries, but it is also a great way of nourishment for the good bacteria within our digestive tract. Besides these, plantain is always a good choice!

2. Tomatoes

Tomato, as nightshade, can be very unpleasant for some people, despite its relatively mild effects.

Tomato-based food can be found literally everywhere because the fruit is quite delicious, and it adds quite a bit of flavor. However, you can go without it and still enjoy all those meals.

If you require marinara sauce for preparing a certain dish, you can substitute it with the so-called Nomato sauce. You can either buy it at a supermarket or make it yourself. Just have some pumpkin puree, fresh basil, kalamata olives, dulse flakes, bone broth, nutritional yeast, and just a bit of beet.

The same Nomato sauce fits great when it comes to chili, and if you’re a lover of enchiladas, zucchinis are the perfect substitution for tomatoes.

3. Red Spices

Red spices are spices based on peppers, such as paprika, and they are almost an irreplaceable part of any meal, especially those more on the, well, spicier side. Almost irreplaceable.

Black pepper, a fairly common, hot spice, is not nightshade but a seed plant, yet it is more than capable of matching that recognizable kick the peppers have.

When it comes the color, where black pepper is lacking, turmeric saves the day. It works as a perfect replacement for peppers. The flavor, the color, the spice – turmeric has it covered!

Finally, if you’re looking for a bit more variety, cumin is the right choice.

Much like black pepper, it is a seed plant, and since it’s green in color, experimenting with it could be quite amusing.

Add it instead of peppers, and watch your dinner guests puzzled expressions as you serve them a delicious, verdantly green chili!

4. Eggplants

Eggplants are also one of the most commonly used nightshades.

One good way of substituting them is the introduction of zucchinis.

Their texture is similar to that of eggplants and prepared as French fries, they’re almost the same as eggplant parmesan.


Depending on the auto-immune decease you’re suffering from and of many other health factors, yes, it is possible for you to stop being sensitive to nightshades, or at least reduce your body’s reaction towards them.

Some people may have a more or less stronger reaction towards a particular type of nightshade, so reintroducing them into your everyday diet in ever so small amounts may help you build tolerance.

But if your previous reaction towards, say, potatoes were serious, it would probably be best if you simply remove it altogether.

There are some efficient ways to achieving this, and you can find them here.


To reiterate, nightshades are essentially harmless for you, they’re even beneficial, but only if you yourself don’t have any overly extreme health issues. If you’re suffering from any form of auto-immune decease, it would be wise for you to avoid nightshades.

The concentration of alkaloids and lectins in them can worsen your chronic pain, irritate your bowels, or cause some more serious consequences.

There are ways, however, to heal your nightshade sensitivity, or at least increase your tolerance towards nightshades, but it is strongly advised you do this with extreme care.

Check your levels of sensitivity, and act accordingly.

Health always comes first!

The Truth About Nightshades - and Whether You Should Avoid Them

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