Tomatoes (Solanum lycopersicum) are some of the easiest plants to grow, making them a favorite among home gardeners and farmers alike. And just a few tomato plants can produce enough tomatoes to keep you going from midsummer through early fall. Yes, there’s much to love about the ubiquitous tomato plant. But how much do you really know about tomato nutrition? Why not come with us as we uncover just how healthy the humble tomato really is!
Are Tomatoes a Vegetable or Fruit?
In the 1890s, the case of a fruit importer, angry at having to pay a vegetable tax on tomatoes, was heard before the United States Supreme Court.
When the Court handed down its ruling, the importer was no doubt shocked to learn he’d lost the case because, in a somewhat bizarre twist, it was determined that, while tomatoes may technically be considered fruits, they’re generally served as part of dinner—not as dessert. Thus, it was perfectly legal to consider tomatoes vegetables under customs regulations.
While this may be the kind of case that leaves you wondering why the Supreme Court of the 19th century had nothing better to do than hear cases about tomato taxes, the truth is that the Court was right—at least about tomatoes being technically fruit.
What’s the difference, you ask?
To be, well, technical, a fruit is the seed-bearing part of a flowering plant that develops from an ovary. But a vegetable is derived from every other part of the plant, including the stem, leaves, and roots.
A Brief History of the Tomato
Although tomatoes are now considered the most popular fruit in the world, they didn’t exactly get off to the most promising of starts.
Tomatoes originated in the Americas, where they’re known to have been enjoyed by the Aztecs as early as 700 CE. The Aztec name for tomato, xitomatl (from which the modern name was derived), means “a plump thing with a navel.”
Tomatoes were first brought to Europe in the early 16th century, where they were initially believed to be poisonous due to their bright red appearance. While the Europeans were mistaken in their assumption, tomatoes are members of the nightshade family, some of which are indeed toxic.
By the late 18th century, tomatoes had earned the nickname “poison apple” after aristocrats began to become sick and die after eating them. However, it wasn’t the tomatoes that were to blame.
At the time, it was common for wealthy Europeans to eat off pewter plates, which contain a large amount of lead. So when these aristocrats ate acidic tomatoes on their pewter plates, the lead leached from the plates, into their food. Thus, the aristocrats were actually dying of lead poisoning.
Sadly, the tomato continued to be feared throughout Europe for decades, until the invention of pizza in Naples in the late 19th century—a turn of events that possibly confirms what scores of children have believed for years: pizza really is the world’s most perfect food.
But it wasn’t just Europeans who feared the glossy red fruit.
When it arrived in the New World in the early 18th century, fears surrounding tomatoes lingered. And these fears were only heightened when the first tomato worm was spotted. The sight of these horned worms was so disturbing that even Ralph Waldo Emerson was afraid they would impart a “poisonous quality to the fruit if [they] should chance to crawl upon it.”
Of course, the worms were eventually proven harmless, as were the tomatoes, and Americans got over their trepidation. In fact, the humble fruit had become so popular by the mid-19th century that it was being used at markets to help sell other plants.
Now that we’ve explored the strange and somewhat complicated history of the tomato, let’s discuss the many sides of tomato nutrition.
Tomato Nutrition Facts
Tomatoes are truly a superfood powerhouse. They’re not only naturally low in sodium and total fat (saturated fat, polyunsaturated fat, and monounsaturated fat), but they’re also a good source of thiamin, niacin, vitamin B6, folate, phosphorus, copper, and magnesium.
In addition, tomatoes are made up of about 95% water, with the remaining 5% being comprised of mostly fiber and carbohydrates (about 3 grams of carbs in total). And a medium tomato contains only 22 calories or so, plus absolutely no trans fat, which makes this one fruit that’s perfect for those who want to keep nutrition high and calories low.
But tomatoes are probably best known for their numerous free radical–scavenging antioxidants, including vitamin E, beta-carotene (which converts to vitamin A in the body), lutein, vitamin C, and lycopene—the carotenoid that gives tomatoes their red color.
With over 10,000 varieties, it’s no wonder tomatoes have become a favorite ingredient in cuisines all over the world. Tomatoes come in a variety of sizes as well, from the marble-sized grape or cherry tomato to the huge, meaty beefsteak tomato.
Tomatoes also come in almost every color nature has to offer, from deep red to orange, yellow, and green. Believe it or not, there are even purple and chocolate-colored tomatoes!
Two basic types of tomatoes are most commonly grown: determinate and indeterminate.
Determinate tomatoes grow as a bush that’s about 3 or 4 feet high. Tomatoes are considered determinate when flower buds form at the ends of the leaves and produce fruit, ripen, and die at approximately the same time.
A popular type of determinate tomato is the Roma tomato.
By contrast, indeterminate tomatoes are tomatoes that grow like vines. These types of tomatoes are called vining tomatoes and need a stalk or cage to support their branches. They also continue growing and producing fruit until killed by frost, with some varieties reaching as much as 12 feet in height. Because of their continual growth, indeterminate tomatoes generally produce more fruit than determinate varieties.
Beefsteak tomatoes are commonly grown indeterminate tomatoes.
Health Benefits of Tomatoes
Tomatoes are chock-full of vitamins and minerals, but it’s their many antioxidants that have really been the subject of scientific research.
Studies have consistently shown that the phytonutrients in tomatoes, including flavonoids, carotenoids, and saponins, as well as fatty acids, can help fight oxidative stress—a condition that can lead to diseases associated with chronic inflammation, such as diabetes, cancer, cardiovascular disease, chronic obstructive pulmonary disease (COPD), and arthritis.
Moreover, studies have found a direct link between tomato antioxidants and a reduced risk of heart disease. Lycopene, in particular, has been found to aid heart health by lowering blood pressure and decreasing lipid peroxidation—a process that leads to the formation of harmful free radicals.
Free radicals can cause significant damage to DNA, which can in turn lead to accelerated aging and disease. Without sufficient antioxidants to counteract lipid peroxidation, a chain reaction can be initiated that may eventually result in chronic diseases like inflammatory bowel disease, Parkinson’s disease, atherosclerosis, and kidney disease.
The phytonutrients in tomatoes are also fantastic at regulating levels of fat in the blood and have been shown to decrease both LDL cholesterol—the so-called bad cholesterol—and triglyceride levels.
What’s more, lycopene has been found to be effective in the prevention of a number of cancers, including lung, pancreatic, ovarian, skin, breast, and prostate cancers. This same carotenoid has also been shown to reduce the risk of fatty liver disease—a condition that can lead to liver cancer if not treated.
In addition, tomatoes have been found to possess compounds that prevent platelets from clumping together and causing blood clots. This finding may have especially important implications for the treatment of cardiovascular disease, as blood clots within blood vessels can break free and cause a heart attack or stroke.
Moreover, the antioxidants in tomatoes have been found in studies to protect the skin against damage from UV rays, which is linked to a decreased skin cancer risk.
So Our Advice? Eat More Tomatoes!
Even if you don’t already love tomatoes, based on the evidence, including just one or two servings in your diet each week may be enough to provide a measure of protection against a number of health problems.
And whether you enjoy raw tomatoes, fresh off the vine, or prefer tomato juice, tomato sauce, tomato puree, or tomato paste, there are as many ways to incorporate tomatoes into your life as there are varieties of tomatoes to choose from.
While any tomato is better than no tomato, organic (and locally grown) tomatoes are certainly best. Conventionally grown tomatoes also, unfortunately, made the Environmental Working Group’s list of 12 most contaminated fruits and vegetables—the Dirty Dozen—again in 2019.
Most experts will also probably tell you that, when in season, fresh tomatoes are generally preferably—though canned tomatoes certainly have their place. After all, they’re not only super easy and ready to add to any recipe, but they’re also processed using heat, which helps free up the lycopene and make it more bioavailable.
Like fresh tomatoes, don’t buy just any canned tomatoes. Instead, look for organic tomatoes packed in cans that aren’t lined with bisphenol A, or BPA. This particularly nasty endocrine disruptor has been linked in studies to infertility, precocious puberty, and breast and prostate cancers.
However, the good news is that more and more companies are phasing out BPA—just be sure to look for the “BPA Free” label. Or you can look for tomatoes packed in either glass (always a great choice) or aseptic cartons.
And once you’ve found that perfect, organically grown, BPA-free, flawless specimen of a Solanum lycopersicum, you’re free to let your imagination take you where it wants to go.
So whether you prefer your tomato products fresh, cooked, or lightly sautéed and drizzled with olive oil à la Mediterranean, go grab some tomatoes today. Your free radicals won’t know what hit ‘em!