Surprisingly for many, tomatoes are a kind of fruit.
They also play a significant role in the cuisine of almost all world cultures.
Tomatoes taste great and add a depth of flavor whenever we use them.
But what is their nutritional value? How many carbs are in tomatoes? And what does lycopene do?
This article will examine many of the frequently asked questions about tomatoes.
What Are Tomatoes?
Tomatoes are, botanically, an edible berry that grows on tomato plants.
They are part of the nightshade family of plants, which also includes eggplant and peppers.
The tomato is also one of the most popular foods in the human diet.
Tomatoes play a significant role in home cooking, and they are also a favorite ingredient for the food industry.
Is Tomato a Fruit or a Vegetable?
People often feel surprised when they find this out, but tomatoes are a fruit.
Specifically, tomatoes are the ovary of a flowering plant. They contain seeds – the definition of fruit.
However, culinary speaking, people treat tomatoes as a vegetable. Tomatoes enjoy widespread popularity and their use is prevalent in international cuisine.
Pizza, chicken tikka masala, salsa, spaghetti bolognese and many other dishes wouldn’t exist without this small red fruit.
Tomatoes have a decent nutritional profile. It’s important to realize that there are many different species of tomatoes, all with a very slightly different nutritional profile.
With this in mind, we’ll take a look at several of the more common tomato varieties a little later on.
First, standard tomatoes contain 18 calories per 100g (1).
- Carbohydrate: 3.9g
- Fat: 0.2g
- Protein: 0.9g
How Many Carbs in Tomatoes?
There are 3.9g of carbs in tomatoes, 1.2g of which is fiber and 2.6g sugar. So tomatoes do have carbs, but not as many as most fruits do.
What Nutrients Do Tomatoes Provide?
Standout nutrients in tomatoes include vitamin C (21% RDA) and vitamin A (17% RDA).
Tomatoes also offer a reasonable amount of vitamin K (10% RDA) and potassium (7% RDA).
Varieties of Tomatoes
All in all, there are dozens of varieties of tomatoes throughout the world. If you take a visit to a farmers market, you can probably find some unique breed that you’ve not yet seen.
For the purpose of this article, we’ll just stick to the most common conventional types of tomato that we can find.
These varieties include:
- Beefsteak tomatoes
- Campari tomatoes
- Cherry tomatoes
- Grape tomatoes
- Kumato tomatoes
- Roma tomatoes
Otherwise known as brown tomatoes, selected breeding in Spain first cultivated Kumato tomatoes.
Kumatoes are now growing across much of Europe and also Central America.
The Kumato tomato is slightly higher in carbs than regular tomatoes. Compared to a standard red tomato, the Kumato contains a higher amount of fructose.
Unfortunately, no verifiable data exists on the exact nutritional profile of Kumato tomatoes.
Cherry tomatoes are small and round, typically the size of a cherry. Salads make use of them as they provide a crunchier, juicier taste than regular tomatoes.
It might surprise you, but cherry tomatoes have been around for centuries and they were the first tomato grown in Europe.
Cherry tomatoes have a similar nutritional and carbohydrate content to standard tomatoes. Salads tend to use cherry tomatoes the most.
Grape tomatoes are similar in size to cherry tomatoes. However, they are more of an oblong shape.
Despite their similarities to cherry tomatoes, they have a thicker skin, less water content and smaller amounts of fructose. As a result, these tomatoes are probably slightly lower in carbs.
Roma tomatoes are one of the most popular versions of tomatoes in grocery stores.
Commonly grown in the United States, United Kingdom, and Australia, producing tomato paste is one of the main uses of them.
Roma tomatoes are also typically an oblong shape and share a similar appearance to grape tomatoes.
Beefsteak tomatoes are the biggest commonly available tomato. Fast food chains frequently use these tomatoes in their stores.
A version of beefsteak tomatoes named “Gigantomo” made media waves upon going on sale in the UK in 2015.
Gigantomo is quite a fitting name given the tomatoes weigh in at three pounds per single fruit.
As the largest variety of tomato, there are more carbs in these tomatoes, as well as overall nutrients.
People often confuse Campari tomatoes for cherry tomatoes.
They are somewhere in between cherry tomatoes and plum tomatoes when it comes to size.
Key Point: There are hundreds of varieties of tomato, but the above are the main tomatoes we can see in-store each day. All have a similar nutritional profile.
Do Tomatoes Have Antioxidants?
Tomatoes are a great source of lycopene, a phytonutrient with antioxidant activity in the body (1).
Lycopene is a carotenoid, although it does not have vitamin A activity.
It is worth noting lycopene is red and is responsible for giving tomatoes their deep red color. As a result, the deeper the red color of a tomato, the more lycopene will be present.
What Are the Benefits of Lycopene?
Lycopene lays claim to some impressive health benefits and has a promising range of studies behind it.
Some of the research findings on lycopene:
- A meta-analysis of prospective studies examined levels of lycopene in the blood of CVD patients. The study found that lower concentrations of lycopene in the blood significantly associated with higher CVD mortality (2).
- In randomized controlled trials, lycopene supplementation reduces health markers of oxidative stress (3).
- Lycopene plays an essential role in the maintenance of good prostate health. Further, in trials it has shown promise for its ability to prevent prostate cancer in aging men (4).
- In a literature review covering 72 studies, the authors claimed the science supports tomatoes reducing lower cancer risk. They stated that the consistency of evidence supports the link between lower cancer rates and tomato consumption. (5).
- In a randomized, double-blind trial, lycopene supplementation improved endothelial function in CVD patients (6).
- Lycopene consumption appears to improve lung function in people living with asthma (7).
- Lycopene ingestion through tomato paste intake reduces UV-induced damage in controlled trials. In other words, eating tomatoes every day offers sun-protective benefits (8).
Key Point: Lycopene is predominantly found in tomato products and has some impressive health benefits.
How Can I Get Lycopene?
Lycopene is present in all tomato products. However, fresh and processed tomatoes have a few differences.
While cooking often reduces the nutritional content of food, it is the other way round for lycopene.
Fresh Tomatoes vs. Processed Tomatoes
Studies show that heat-processed tomatoes provide a better lycopene source than fresh ones do (9).
Cooking a tomato breaks down the cell structure, making lycopene more accessible to the body.
However, some studies show no difference between lycopene content in fresh and processed tomatoes (10).
Despite this contradiction, there is a good explanation for this.
Although heating tomatoes will improve the lycopene’s bioavailability, it’s may also have drawbacks. The reason for this is that high-heat can also degrade lycopene.
A 2015 study on the effects of cooking tomatoes provides some helpful details on this (11).
- The lycopene content in the raw tomato used in this study was 331mg per 100g.
- Among the three cooking methods, all degraded the lycopene content. The higher the cooking temperature, the more the lycopene degraded. Pan-frying showed the biggest loss in lycopene levels.
- The study demonstrated that lycopene isn’t stable at temperatures above 100◦C.
It’s also worth remembering that lycopene is a fat-soluble nutrient.
To emphasize this point, consumption of a salad without fat showed no measurable increase of lycopene in the body. On the other hand, a salad consumed with avocado led to a 4.4-fold increase in lycopene (12).
The lesson? If you want the full benefits of tomatoes, make sure you’re eating enough fat with them.
Key Point: To absorb the most lycopene, cook tomatoes on a low heat and eat them in the context of a meal containing adequate fat.
Is Tomato Paste Healthy?
Produced by cooking tomatoes for several hours to remove the moisture, tomato paste should contain 100% tomato. Tomato paste also has a much deeper flavor, and only small amounts are necessary.
One of the great things about tomato paste is that the lycopene content is more bioavailable than in fresh tomatoes.
In a study, one group of participants consumed 400g (23mg lycopene) of fresh tomatoes with corn oil. Another group ate 40g (23mg lycopene) of tomato paste with corn oil.
Blood samples were taken both before and after the meals, which showed the tomato paste group’s blood contained 2.5x more lycopene (13).
Carbs in Tomato Paste
The number of carbs in tomato paste is much higher than fresh tomatoes, so go easy on it.
Tomato paste is also much more nutrient-dense than fresh tomato due to the lack of moisture.
On a per 100g basis, tomato paste contains 18.9g carbohydrate, 12.2g of which is sugar (14).
If you compare this to fresh tomatoes (5g per 100g) then you can see there’s a huge difference.
Key Point: Tomato paste, as a heated product, contains a more bio-available form of lycopene. Tomato paste is also more concentrated, so there are more carbs in tomato paste.
Is Tomato Ketchup Healthy?
Tomato ketchup also goes through a cooking process. It’s similar to tomato paste, but with extra added ingredients.
As these additions include a large amount of sugar in the form of high-fructose corn syrup, it’s not something I’d call healthy.
Other ingredients added to ketchup include salt, vinegar and “natural flavoring.”
Sure, it’s true that a small serving will only be a minimal amount of sugar. However, we are all eating far too much sugar, so the more of these things that we remove from our diet, the healthier we will be.
On the positive side, ketchup should also have a decent lycopene content. Then again, this doesn’t mean ketchup is ‘good’ for you.
Carbs in Tomato Ketchup
The carbs in tomato ketchup are the highest among tomato products.
On a per 100g basis, ketchup has 27.4g carbs. Sugar content makes up 21.3g of this (15).
In short, more than 20% by weight of ketchup is pure sugar. Unfortunately, the fiber content is also much lower than real tomatoes and tomato paste too (0.3g per 100g).
As with most processed food, nutrient values tend to fall the more removed a food is from its ‘whole food’ form.
Instead of buying ketchup, why not try making a healthy homemade version? There is a great one here if this is something that appeals to you.
Key Point: Although ketchup also contains lycopene, it is too high in sugar and best to avoid.
Tomatoes are tasty, adaptable and have a pretty decent nutrient profile.
The studies into lycopene are intriguing, and it seems like this antioxidant has some significant health benefits.
However, make sure to remember that no one nutrient is a miracle cure alone. It is the total composition of our diet that matters more than anything else.