After four newsletters of explaining exactly how beneficial fruit and vegetables are, it feels strange to give a warning against some of them for your health and well-being.  This is exactly what this newsletter intends to do.  Without taking away anything that was said in the previous four newsletters, this one sheds some light on a group called the ‘Nightshades’ – no pun intended. 

In short, nightshades form a group of plants which may, under certain circumstances, contribute to pain and inflammation in people with compromised digestion and immunity. The very same substance causing the harm, could be beneficial to those with healthy digestive tracts and immunity systems.  As a family, these plants contain alkaloids which were initially intended to harm their natural enemies making it difficult for them to move.  In humans, it mainly causes pain and inflammation in the joints and muscles.

The following plants belong to this group: (The list was obtained from a GreenMedInfo article)

·       tomatoes

·       potatoes (excluding sweet potatoes or yams)

·       eggplant

·       okra


·       goji berries

·       tomarillos (a plum-like fruit from Peru)

·       sorrel

·       garden huckleberry & blueberries (contain the alkaloids that induce inflammation)

·       gooseberries

·       ground cherries

·       pepino Melon

·       Belladonna (also used as a homeopathic remedy)

·       tobacco

·       paprika

·       cayenne pepper

It is important to remember that not all these plants have the same level of these substances and in each plant the substance looks a little different, changing the effect it potentially has.  Also keep in mind what was said previously; that in a human with a healthy digestive system and immunity these effects may contribute to their health while the negative effects mainly affect those with compromised digestion and immunity.  The adverse effects also depend on the regularity and amounts of which these plants are consumed.

Here is what research has discovered about the nightshades:

1.     The alkaloids in potatoes are mainly concentrated in the skins.  This is the plant with the most alkaloids.  The consumption of it by persons with compromised gut health could lead to leaky gut and Irritable Bowel Syndrome.

2.     As these pathogens accumulate in the body it might lead to joint and muscle aches and pains and very well aggravate arthritis in the body.

3.     Although tomatoes are part of this family of nightshades, there are literally hundreds of scientific articles proving the positive effects of this plant on health – from treating and prevention of cancer to heart health promotion and much more.  Although there are some negative reports about the possibility of poisoning with the alkaloids in tomatoes, I did not find any objective studies to prove it.

4.     While eggplants are known for their high levels of antioxidants in the skin, they store alkaloids in the seeds and in the flesh.  Soaking it in salt water removes most of it.  It also contains much less alkaloids than potatoes. 

5.     Regarding peppers, the least toxic ones are the green and red sweet peppers.  Black pepper is often exempted from this list.  And like the rest of the nightshades, there are many articles proving health benefits which could be obtained from consuming peppers. 


Not too many people have reactions to the nightshades.  However, if you have reservations about the matter and especially if you suffer from arthritis or any other autoimmune disease, it is worth testing yourself.  It will be worth abstaining from the whole list of plants for three months and then include them into your diet one by one to see how they affect you.  During the three months it will be wise to improve your gut health and detoxify before introducing your favorite foods back into your diet.

When you prepare the different nightshades it is important to follow these rules to make them less toxic:

1.     In general these foods are less toxic in season and also cooked.  As it matures it also loses some of its toxicity; therefore, always consume it on the riper side. 

2.     Because most of the alkaloids are found in the skin of the potato, always remove the skin before preparing it. Unripe and sprouting potatoes have the highest concentration of alkaloids as well as fried potatoes.

3.     Green tomatoes also have more of these toxins than the ripe ones.  It seems as if removing the seeds as in tomato sauce will also reduce toxicity and increase the level of lycopene which is known to protect from some cancers.

4.     As with tomatoes and potatoes, ripe eggplant seems to have fewer toxins than greener ones.  Because the alkaloids are stored in the flesh, soaking them is advised.  It removes some of the toxicity. 

5.     As mentioned earlier, red and green bell peppers have less alkaloids than other peppers and much less than potatoes.