Tomato Nutrition Facts

Have you ever wondered if a tomato is a fruit or a vegetable? Botanists classify tomatoes as a fruit because they develop from the ovary of flowering plants and contain seeds. However, because tomatoes are prepared and served like vegetables, they are often thought of as a type of vegetable. Regardless of the category tomatoes fall into they are delicious and nutritious.

The following nutrition information is provided by the USDA for one small, whole tomato measuring 2 2/5" in diameter (91 g).

• Calories: 16
• Fat: 0.2g
• Sodium: 4mg
• Carbohydrates: 3.5g
• Fiber: 1.1g
• Sugars: 2.4g
• Protein: 0.8g

Tomatoes are low in calories and low in carbs. There are 3.5 carbs in a small tomato, making these a low-carb food. Most of the carbohydrate in tomatoes is fiber (2.4 grams).

The size of the tomato and the portion you consume will affect the calorie and carbohydrate content. For example, one cherry tomato contains around 3 calories and 0.5 grams carbohydrate, one plum tomato contains about 11 calories and 2.4 grams carbohydrate, one thick slice of tomato contains about 5 calories and 1 gram of carbohydrate, and one cup of chopped tomatoes contains 32 calories and 7 grams carbohydrate.

The glycemic load of tomatoes is estimated to be two when you consume one serving.

Tomatoes contain a very small amount of fat, less than one gram per serving.

There is just under one gram of protein in a small tomato.

Tomatoes provide vitamins and minerals including vitamin C, vitamin A, vitamin K, and potassium.

Tomatoes provide health benefits from the vitamins that they provide.

The vitamin C in tomatoes is important for wound healing, strong bones and teeth, good immune function and helps to increase iron absorption. 

Lycopene is an antioxidant that has been been associated with a reduced prostate cancer. Additionally, lycopene can increase HDL (healthy cholesterol) and reduce LDL (bad cholesterol). Some studies have shown a relationship between lycopene in tomatoes and the reduction of the presence of oxidized LDL, which can contribute to the plaque on the walls of the arteries.

Tomatoes are also an excellent source of vitamin A, which is an essential component for normal vision and immune function. They are also a very good source of vitamin K, which assists in blood clotting and potassium, which can help to reduce blood pressure. 

Below are answers to common nutrition-related questions about tomatoes.

Is tomato sauce high in carbohydrates?

The number of carbohydrates in a typical tomato sauce will depend on whether or not the recipe has sugar in it. Some types of sauce, such as marinara, do not require sugar, whereas many tomato sauce recipes yield a sweeter sauce because of the sugar content.

If you are purchasing tomato sauce from the store always read the label. Some types of jarred sauce can contain as much as 100 calories and 18 grams carbohydrate per serving. However, a general nutrient profile for one-half cup of canned tomato sauce is about 40 calories, 0 grams fat, 820 mg sodium, 8 grams carbohydrate, 2 grams fiber, 4 grams sugar, 0 grams protein. Note that the sodium content tends to be very high in canned sauce and, if you are making your own sauce, you can reduce the sodium content by choosing tomatoes that have no salt added to them.

How do I pick the best tomatoes?

Look for fresh tomatoes that are plump with smooth, shiny skin. The color should be uniform and consistent for the variety.

You can also purchase canned tomatoes, pureed, tomato paste, sauce, or stewed varieties. Note that many of these products have added sodium to extend shelf life.

Sun-dried tomatoes, which are tomatoes that have been dried, are also available all year long and are sold in crumbs, pieces, slivers or halves, either dry or packed in oil. Those that are packed in oil can be rich in sodium and calories and, therefore, your portion should be monitored. You can also drain them before use to reduce the calorie and sodium content. 

What are some different varieties of tomatoes?

Tomatoes are available in a variety of shapes (from tiny spheres to large ovals), colors (from green to red, yellow, and orange), and sizes (from small grape tomatoes to large beefsteak tomatoes). They also vary in the level of sweetness and acidity, which depends on the growing conditions and ripeness at harvest. Some tomatoes have few seeds, such as the plum, whereas others have many more.

Should tomatoes be refrigerated?

Contrary to popular belief, do not store fresh tomatoes in the refrigerator, in fact, this can turn the flesh mealy and reduce the flavor. Instead, store in a cool, dry place.

Tomatoes are used often in salads, soups, dips (like guacamole), sauces, and baked dishes. They are most often eaten raw, but heating tomatoes with a small amount of fat increases its nutrient profile by increasing the bioavailability of lycopene.

To cook tomatoes, consider sautéing, grilling, or roasting. Roasting yields a juicy, concentrated flavor and texture. To roast, season tomatoes with oil, garlic, red pepper, and other herbs and spices—eat plain or use roasted tomatoes to puree for a tomato sauce or as a topper for grilled, baked, or roasted meats, chicken, or fish.

You can also use tomatoes to make tomato or a simple marinara sauce or use tomato sauce and tomato products to flavor foods such as spaghetti squash, chili, and stews. Season your sauce however you'd like, using basil, oregano, parsley, or garlic.

If you have oral allergy syndrome you may experience a reaction when you consume tomatoes. According to the American College of Allergy, Asthma, and Immunology OAS is also known as a pollen-food syndrome, and is caused by cross-reacting allergens found in both pollen and raw fruits, vegetables, or some tree nuts. The source notes that people with a known allergy to grass may also experience symptoms when consuming celery, melons, oranges, peaches, or tomato. Symptoms may include itchy mouth, ears or throat, or swelling of the lips, mouth, tongue, and throat. 

If you suspect an allergy to tomato, seek the advice of a qualified healthcare professional.