Tomatoes are not commonly listed as a food trigger for gout, a form of inflammatory arthritis caused by the formation of uric acid crystals in a joint. However, some people report tomatoes as a trigger food, and limited research suggests they may increase uric acid levels in some people with the condition.

Gout results in pain, inflammation, and swelling, often in the big toe joint. Avoiding foods that contain substances that raise uric acid levels in the blood is one way of reducing painful flare-ups of gout. Gout affects over 9 million Americans.

What Research Says

Limited research exists on how tomatoes might affect gout. Health organizations, such as the Arthritis Foundation, do not list tomatoes as a food trigger for gout.

In gout, uric acid (urate) crystals are deposited in a joint, causing painful inflammation and swelling. Uric acid is produced by the breakdown of chemicals called purines, which are found in body tissues and some foods. Fresh tomatoes are not high in purines.

High levels of uric acid in the blood can lead to the formation of urate crystals around the joints. Avoiding foods high in purines is one way of keeping uric acid levels low. This may be enough to prevent painful flare-ups of the condition. A gout flare is a sudden, painful episode. It most often affects the big toe.

A 2015 study found that tomatoes were the fourth most common reported food trigger for gout in a sample of 2,051 people. The study found an association between tomato consumption and higher uric acid levels. However, data from previous studies have been contradictory.

The researchers suggested a biological basis (underlying physical, neurological, or genetic factors) for any association. While tomatoes might lead to a gout flare in one person, they may not cause a reaction in another.

Are Tomatoes High in Purines?

Foods high in purines and those that raise uric acid in other ways can lead to gout attacks. These include meat (mainly organ meats), most seafood, alcohol, and sweetened drinks.

People with gout may be counseled to limit or avoid these foods as one way to prevent a gout flare. However, dietary changes only result in small changes in uric acid concentration, while medication can reduce higher levels of uric acid.

Fresh tomatoes are very low in purines, but they contain high levels of glutamate, an amino acid (building block of protein) often found in purine-rich foods. Glutamate may stimulate or increase the processes that lead to higher uric acid levels.

Tomato products, like tomato paste, sauce, and ketchup, may contain added sugars and additives, which can aggravate gout.

How to Tell If Eating Tomatoes Worsens Gout

The best way to tell if tomatoes are causing gout symptoms is to eliminate tomatoes and tomato products for a few weeks to see if symptoms improve. If tomatoes are causing your gout to flare up, removing them from your diet may improve symptoms.

Consider keeping a detailed record of your food intake to help you pinpoint what is causing your gout to flare up.

You will want to track:

• Everything you eat and drink each day
• Your fluid intake
• Level and locations of pain throughout your day
• How much sleep you are getting
• All medications and supplements you take daily
• Daily exercise and activity
• Your mood
• Energy levels

If you detect patterns of flare-ups related to your diet, consider making changes to help reduce gout flares. You may also want to share your tracking and any relevant information with your healthcare provider.

Nightshades and Inflammation

Some people with arthritic conditions like gout have reported that eating nightshade vegetables like tomatoes, eggplant, and peppers can worsen their inflammation, swelling, and stiffness. Others say that these foods actually help lessen arthritis symptoms.

These plants contain a substance called solanine, which may interfere with healthy gut bacteria and indirectly increase inflammation in the body. Solanine-containing vegetables also contain other substances that may actually bring down inflammation, like vitamin C, lycopene, antioxidants, phytochemicals, and flavonoids, which might explain why their effects vary.

Nightshades have not been found to worsen gout symptoms or cause gout flares. Many of these foods are also low in purines and can be helpful for not triggering flares.

The Arthritis Foundation recommends that people who suspect nightshade vegetables are worsening their arthritis symptoms should exclude these foods from their diet. Reduce these foods for a couple of weeks to see if symptoms improve, and reintroduce them one at a time to determine if symptoms return.

What to Eat With Gout Besides Tomatoes

Tomatoes are a nutritious food that may provide various benefits to people with gout. This is because tomatoes are rich in vitamin C and lycopene, substances that eliminate inflammation. Gout is an inflammatory condition, so lowering inflammation may reduce gout flares rather than increasing them.

If tomatoes are a gout trigger for you, consider replacing them with foods that have a similar health profile.

Gout-friendly fruits and vegetables that are rich in vitamin C and/or lycopene include:

• Asparagus
• Broccoli
• Cauliflower
• Grapefruit
• Guavas
• Kale
• Mangoes
• Persimmons
• Red cabbage
• Sweet red bell peppers
• Watermelon
• Yellow bell peppers

Foods that can replace tomatoes in your favorite dishes and tend to be gout-friendly include:

• Beets
• Bell peppers
• Eggplant
• Squash

Summary

Tomatoes are a low-purine food that is not generally recognized as triggering gout. Limited research shows that some people report tomatoes as triggering a gout flare, possibly due to other substances that could raise uric acid levels. However, other helpful substances in tomatoes may reduce inflammation and gout symptoms.

Keeping a food journal is the best way to know if tomatoes may trigger gout. If tomatoes trigger your gout, consider less-triggering foods, like beets or eggplant, as a substitute for tomatoes.