How Tomatoes in some people can contribute to IBS symptoms like diarrhea and bloating. Mainly due to being a High Histamine and High Acid food. #Functionalmedicine #DranshulguptaMD #IBS

Can Tomatoes Trigger IBS?

Inside: How can tomatoes affect IBS symptoms. Can tomatoes be the IBS trigger for some people and how tomatoes can cause diarrhea and bloating symptoms for some people with IBS.

Irritable bowel syndrome aka IBS is a very common disorder worldwide and millions of people suffer from daily symptoms.

IBS affects the quality of life and most of the people keep thinking about why they suddenly developed this disorder and don’t know how to manage this condition.

The most common symptoms of IBS are constipation, diarrhea, bloating, abdominal pain. People often feel worse after eating food but are not able to pinpoint exactly which food might be the problem.

Multiple times people have commented that they feel tomatoes are their enemies and that they make their IBS symptoms worse specially diarrhea and bloating.

So — I decided to look into this in detail and see why tomatoes could worsen IBS symptoms. 

Tomatoes and IBS

Tomatoes are so healthy and have so many good vitamins, minerals, are a good source of the antioxidant (lycopene) and other phytochemicals. But in some people, it looks like they can trigger their IBS symptoms.

It also happens that small quantities of tomatoes might be tolerated by most people with IBS but huge quantities might trigger diarrhea and bloating.

It also matters in what form tomatoes are being consumed raw, cooked or in processed form like ketchup.

Reasons How Tomatoes Contribute to IBS Symptoms.  

High Histamine food 

Tomatoes are high histamine containing foods. High histamine foods can trigger allergic reactions in people who might be sensitive to them. This reaction can be anywhere from sneezing, tongue swelling, shortness of breath to gut symptoms like food sensitivity, diarrhea, bloating, abdominal pain. Tomatoes can cause high histamine in the body and if your body is unable to process histamine then it can trigger an allergic response which in some people can be gut-related like IBS symptoms. 

High Acid Food

Tomatoes can cause some gut irritation by predisposing individuals to acid reflux issues. Tomatoes are high in citric and malic acid, and in some sensitive individuals, they can lead to acid reflux. This acid reflux further can present with other symptoms like bloating, abdominal pain, and in some cases can cause diarrhea because of causing gut irritation.  


FODMAP are fermentable oligo-, di-, mono-saccharides and polyols. These are carbs that are resistant to digestion and sometimes can contribute towards IBS symptoms.

Now tomatoes on their own are low fodmap food. But there are several different preparations of tomatoes that we use on a daily basis which increases the FODMAP value of tomatoes; one of those is tomato ketchup.

Interestingly, different countries have different ways of producing ketchup. Monash University did the research and checked ketchup from Australia and the USA and came to the conclusion that Australian ketchup was Low FODMAP but the Ketchup from US was not Low FOPMAP.

Most of ketchup in the US is made from high fructose corn syrup or sucrose and thus high FODMAP. And we know that high FODMAP foods can trigger IBS so one more reason for tomatoes to trigger IBS


Tomatoes also fall into the category of nightshades. Nightshades recently have come into limelight because of some concern about their association with autoimmune conditions. Majority of these claims are based on substances found in nightshades like alkaloids.

Tomatoes have alkaloid called Solanine and it is felt that these alkaloids function as a natural insect repellent.

And thus humans who consume them in high quantities can sometimes react and have gut-related or other symptoms. Some patients do feel better when they avoid nightshades and their gut symptoms are actually better but not all.   

These are the reasons how tomatoes through different mechanisms can contribute to IBS symptoms like diarrhea and bloating and sometimes can even trigger IBS.

Now I don’t want everyone to give up tomatoes because I do feel tomatoes have several health benefits associated with them. But I think people who are suffering from IBS and have not been able to identify their trigger foods then they can do a trial run of eliminating tomatoes and see if their symptoms improve. Most of the time this trial run should go for at least 3-4 weeks before you can notice a difference in your symptoms. Plus here is a recommended IBS Diet Plan.

Related Read:

Is SIBO cause of your IBS.

Thyroid Irritable Bowel Syndrome

Stress- The reason your GERD is not improving even after being on medications?

Everything You Need To Know About Leaky Gut

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How can tomatoes affect IBS symptoms. Can tomatoes be the IBS trigger for some people and how tomatoes can cause diarrhea and bloating symptoms for some people with IBS. #tomatoes #ibs #functionalmedicine #DrAnshulGuptaMD
Can Tomatoes Trigger IBS?

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