Tomatoes, officially a fruit, are high in many nutrients and packed with antioxidants like lycopene, vitamin C and beta-carotene. They offer a range of health benefits that even extend to gut health. But, if you’re struggling with IBS, you may be wondering ‘are tomatoes low FODMAP?’ and ‘can tomatoes and IBS be friends’? I’ll talk you through the different tomatoes FODMAP content and answer these questions for you so you can have the confidence to know how to include tomatoes in your IBS or low FODMAP diet.
Contents:
Are Tomatoes Low FODMAP?
Tomatoes and their products can vary significantly in FODMAP content depending on the type and serving size. Monash, the university responsible for developing the low FODMAP diet, retested tomatoes in 2022. Unfortunately they found tomatoes to have higher levels of FODMAPs than was previously thought and they went from having unlimited low FODMAP portions sizes to having specific FODMAP serves.
Fresh tomatoes are generally low FODMAP in smaller portions. Their processed forms, such as sauces and pastes, can become high FODMAP due to increased concentration of FODMAPs like fructose and fructans. Paying attention to serving sizes is key if you have IBS and if you’re following a low FODMAP diet.
Take a look at this summary table showing you the low, medium and high FODMAP serving sizes of all the tomato only products tested by Monash:
| Tomato Product | Low FODMAP Serve | Medium FODMAP Serve | High FODMAP Serve |
|---|---|---|---|
| Tomato, truss/on the vine, raw | 69 g (1/2 medium) | 75 g (1/2 medium) | 93 g (2/3 medium) |
| Tomato, common, raw | 65 g (1/2 medium) | 75 g (1/2 medium) | 91 g (2/3 medium) |
| Tomato, cherry, raw | 45 g (5 medium) | 60 g (7 medium) | 75 g (9 medium) |
| Tomato, Roma/plum, raw | 48 g (1/3 medium) | 64 g (1/2 medium) | 75 g (2/3 medium) |
| Tomato, semi sun-dried, drained | 13 g (3 ¼ piece) | 16 g (4 pieces) | 19 g (4 ¾ pieces) |
| Tomato, round, whole, canned | 100 g (1/2 cup) | 132 g (2/3 cup) | 178 g (1 cup) |
| Tomato, Roma/plum, canned, with juice | 100 g (1/2 cup) | 182 g (1 cup) | 244 g (1 ¼ cups) |
| Tomato sauce | 13 g (2 sachets) | ||
| Tomato puree | 36 g (2 tbsp) | 48 g | 50 g (3 tbsp |
| Tomato paste/concentrate | 28 g (2 tbsp) | 81 g (1/3 cup) | 85 g (1/2 cup) |
| Pasta sauce, tomato-based (contains garlic and onion, commercial) | 66 g (1/4 cup) | ||
| Tomato juice, 100 % | 96 g (1/2 glass) | 129 g (2/3 glass) | 200 g (1 glass) |
Fresh tomatoes FODMAP content
Fresh tomatoes are low in FODMAPs when consumed in small portions, but larger servings contain higher levels of fructose, which can trigger symptoms in sensitive individuals.
Tomato, Truss/On the Vine, Raw
Low FODMAP at 69 g (1/2 medium); becomes high FODMAP at 93 g (2/3 medium) due to fructose. These have the most generous serving size of all the raw tomatoes. Use fresh or cooked in small servings.
Tomato, Common, Raw
Low FODMAP at 65 g (1/2 medium); becomes high FODMAP at 91 g (2/3 medium) due to fructose. Enjoy fresh in salads or as a snack within the low FODMAP serving.
Tomato, Cherry, Raw
Low FODMAP at 45 g (5 medium); becomes high FODMAP at 75 g (9 medium) due to fructose. Ideal for topping salads or roasting, but limit your portion sizes to five if you’re sensitive to fructose or following a low FODMAP diet.
Tomato, Roma/Plum, Raw
Low FODMAP at 48 g (1/3 medium); becomes high FODMAP at 75 g (2/3 medium) due to fructose. Limit these on the low FODMAP diet to just 1/3 of a medium tomato.
Try this delicious low FODMAP recipe for Tempeh Taco Bowl which includes fresh tomatoes.
Canned and dried tomatoes FODMAP content
Canned and dried tomatoes are higher in FODMAPs due to their concentrated fructose and, in some cases, fructan content, making portion control essential for those managing IBS symptoms.
Tomato, Semi Sun-Dried, Drained
Low FODMAP at 13 g (3 ¼ pieces); becomes high FODMAP at 19 g (4 ¾ pieces) due to fructose. Use in small amounts to get a tomato flavour hit in salads and cooked dishes.
Tomato, Round, Whole, Canned
Low FODMAP at 100 g (1/2 cup); becomes high FODMAP at 178 g (1 cup) due to fructose. Great for stews and sauces, but portion carefully to avoid exceeding the limits if you’re following a low FODMAP diet.
Tomato, Roma/Plum, Canned, with Juice
Low FODMAP at 100 g (1/2 cup); becomes high FODMAP at 244 g (1 ¼ cups) due to fructose and fructan. Like the canned round tomatoes, these are also suitable for sauces with moderate use.
Products of Tomatoes FODMAP Content
Tomato products like sauce, puree and juice can range from low to high FODMAP depending on the portion size, with larger amounts often containing higher levels of fructose and fructans, making moderation important for those with IBS.
Tomato Sauce (Ketchup)
A low FODMAP serving is 13 g (2 sachets). Ketchup is a convenient addition to meals, but the portion size should be kept minimal to remain low FODMAP. Check ingredients for high FODMAP additions, such as fructose, high FODMAP sweeteners and onion or garlic powder, as there are many different types of ketchup available.
Tomato Puree
Low FODMAP at 36 g (2 tbsp); becomes high FODMAP at 50 g (3 tbsp) due to fructose. Use it sparingly as a base for sauces or soups to manage FODMAP levels.
Tomato Juice (100%)
Low FODMAP at 96 g (1/2 glass); becomes high FODMAP at 200 g (1 glass) due to fructose and fructans. Use in small amounts as a beverage or soup base.
Tomato Paste/Concentrate
Slightly more concentrated than tomato puree, tomato paste is low FODMAP at 28 g (2 tbsp) and becomes high FODMAP at 85 g (1/2 cup) due to fructans. Use sparingly in recipes to avoid high FODMAP levels.
Pasta Sauce, Tomato-Based (with Garlic and Onion, Commercial)
High FODMAP at 66 g (1/4 cup) due to galacto-oligosaccharides (GOS) from onion and garlic and fructans. Avoid this or choose a garlic- and onion-free alternative for a low FODMAP option.
FODMAP Stacking
FODMAP stacking occurs when multiple “green serve” low FODMAP foods are consumed in one meal, potentially providing enough FODMAPs to trigger IBS symptoms. While a single green serve portion of tomatoes, such as cherry tomatoes or raw Roma tomatoes, is considered low FODMAP, combining them with other FODMAP-containing foods could lead to stacking. For example, pairing a small portion of low FODMAP tomato puree with other foods high in fructose or fructans, such as bell peppers or sugar snap peas, may exacerbate symptoms for sensitive individuals.
To avoid stacking, it’s important to space meals 2-3 hours apart, monitor portion sizes, and use the Monash FODMAP app to ensure safe combinations. Including tomatoes in controlled portions can still be a delicious and gut-friendly option in a balanced low FODMAP meal plan.
Health Effects of Tomatoes
Studies have found that regular consumption of tomatoes has been linked to a reduced risk of chronic conditions such as cancer, cardiovascular disease, neurodegenerative disorders and diabetes. They may also enhance skin health, immune function and exercise recovery. Tomatoes’ antioxidant-rich profile helps combat oxidative stress, supporting overall health.
Despite these benefits, drawbacks such as potential kidney stone formation, allergic reactions, or contamination from pesticides and heavy metals in low-quality produce are worth noting. To maximise their health benefits, it is important to source high-quality tomatoes and consume them in appropriate amounts.
Tomatoes and IBS
Including tomatoes and tomato products in your diet can positively impact gut health by improving the diversity and richness of the gut microbiome, a crucial factor for digestive health.
Tomatoes help reduce gut-damaging bacteria and increase beneficial strains such as Lactobacillus, aiding in the regulation of inflammation and lowering risks associated with liver disease and inflammatory bowel conditions.
Their antioxidant properties further support the gut barrier function and reduce oxidative stress, potentially lowering the risk of gastrointestinal disorders. However, excessive consumption may lead to issues like heartburn or trigger sensitivities in some individuals, emphasising the importance of moderation.
Conclusion
Tomatoes are a versatile and nutrient-packed addition to your diet, offering a range of health benefits, from supporting cardiovascular and gut health to reducing oxidative stress.
For those with IBS, tomatoes can still be enjoyed on a low FODMAP diet by paying close attention to serving sizes and types. Whether you’re including fresh tomatoes in salads, canned tomatoes in stews, or small amounts of puree in sauces, mindful consumption can help you enjoy their flavours and benefits without triggering symptoms. Are tomatoes low FODMAP? Yes, in small to moderate amounts depending on the type. By understanding their FODMAP content and using them in moderation, tomatoes and their products can remain a delicious and gut-friendly part of your meals.
