Tomatoes rank among the most popular and versatile foods we know. They are loaded with important nutrients and are believed to have heart-health-promoting and even cancer-preventing properties. Tomatoes are low in calories and fats but rich in dietary fiber, minerals and vitamins.
Not many foods can give you so much bang for the buck. Antioxidants, which are present in high amounts in tomatoes, have been found to be protective against many cancers, including colon-, prostate-, breast-, endometrial- (the lining tissue of the uterus), lung- and pancreatic cancers.
Phytochemicals like lycopene and carotenoids protect cells from so-called “free radicals,” molecules known to wreak havoc in the body and accelerate the aging process.
Lycopene has also cardiovascular benefits. Studies have found that a high dietary intake of tomato products significantly reduces total and LDL (“bad”) cholesterol levels.
Vitamin A, also richly present in tomatoes, is essential for the preservation of good vision. In addition, Vitamin A is required for maintaining healthy mucus membranes and skin.
Vitamin C strengthens the immune system and helps building resistance against infections.
Vitamin K helps maintaining bone density because of its ability to activate osteocalcin, a chemical that anchors calcium molecules inside the bones.
Potassium is an important component of cell- and body fluids and also helps to control heart rate and blood pressure.
Especially the red varieties are filled with flavonoids, which can protect against certain cancers, including lung cancer.
All tomatoes are a good source of folate, iron, calcium, manganese and other important minerals the body needs to function properly.
A colorful history
Botanically, tomatoes are actually not vegetables but fruits. Known by the scientific name, “Solanum lycopersicum,” they are members of the “Nightshade” (Solanaceae) plant family, which also includes bell peppers, eggplants and white potatoes.
The name reflects some mystery that has surrounded the tomato plant for centuries. “Lycopersicon” is the Latin word for “wolf peach,” which was probably chosen because of a long-held belief that this fruit was dangerous – as dangerous as a wolf.
The French seemed less fearful and called it “pomme d’amour,” meaning “apple of love.” They believed that eating tomatoes had an aphrodisiacal effect, comparable to Viagra or Cialis today. And in Italy, where tomatoes are arguably the most popular, they call them “pomodoro,” the “golden apple.”
Originally, tomatoes were native only to South America’s west coast, including the Galapagos Islands. The early types cultivated by humans resembled today’s cherry tomatoes. At that time, they were usually not eaten but rather displayed for decoration, like flowers.
The use of tomatoes as food became eventually popular in Mexico, perhaps because the people there were already familiar with a fruit called “tomatillo,” a type of small green tomato (in Spanish: “Tomate verde”) that was a staple in their cuisine. When the conquistadores invaded the country in the 16th century, they took seeds of tomato plants back to Spain. Soon thereafter, tomatoes were introduced all over Europe. The early colonists brought tomato seeds with them to North America. Today, farmers in the United States rank among the top producers of tomatoes worldwide.
Many varieties to choose from
Tomatoes come in many sizes, shapes and colors. In fact, there are thousands of varieties, including hybrids and genetically modified versions. The so-called “heirloom” tomatoes are becoming increasingly popular, especially among organic producers and their clientele.
Heirlooms, a.k.a. “heritage tomatoes,” are open-pollinated, non-hybrid cultivars. Many have been passed down through several generations of growers and are highly valued for their unique flavors, coloring and other characteristics. They too come in all sizes, from beefsteak to cherry. Some have names as colorful as their looks, like “Big Rainbow,” “Cherokee Purple,” “Red Brandywine,” “Green Zebra,” “Red Zebra” – or, how about “Mortgage Lifter”?
Tomatoes taste best when they are freshly harvested during the summer and early fall. The flavors typically change as the season progresses, with most varieties becoming more acidic over time. Unfortunately, tomatoes are subject to a number of diseases, including fungal and bacterial infections, especially in cool rainy weather. Still, I would always recommend choosing the organic kind to avoid exposure to pesticides.
Select only tomatoes with rich, deep colors. The skin should be smooth with no wrinkles, cracks, bruises or soft spots. Ripe tomatoes will yield to a slight squeeze. When buying canned tomatoes, make sure you get a reputable brand. Not all imports follow strict standards for lead content in cans. This is especially important for tomatoes because their high acidity can cause corrosion, which may result in poisoning.
Tomatoes continue to ripen after they are picked. You can keep them at room temperature or put them in the fridge if they are close to becoming overripe. Whole tomatoes and tomato sauce freeze well for future use in cooked dishes. Sundried tomatoes should be stored in airtight containers at a cool temperature.
Many Americans know tomatoes best in form of ketchup. Although it’s not as beneficial as the real thing, tomato ketchup is not completely void of nutrients. Much of the lycopene content remains intact after processing. However, it is worth buying organic ketchup because it contains up to three times more lycopene than regular brands.
Many ways to prepare and enjoy
Eating tomatoes raw and unaltered is the quickest (and perhaps best) way to get all the nutritional benefits. However, cooked tomatoes, which can be used in sauces, purées or soups, contain even higher amounts of lycopene. Tests have shown that chopping and heating makes phytonutrients and other health-promoting components in tomatoes more potent. And tomato paste, especially when the skin is included in the making, has a high concentration of carotenoids.
In addition to enjoying tomatoes just as nature made them, you can dry, bake, roast, sauté, blenderize or utilize them in countless other ways. On a hot summer day, there is nothing better tasting than chilled gazpacho made from scratch. When it gets cooler outside, maybe it’s time for a hearty tomato-based soup with lots of vegetables to be added. Any good vegetarian cookbook will give you plenty of ideas – or you just find out for yourself how versatile tomatoes truly can be.
Timi Gustafson R.D. is a clinical dietitian and author of the book “The Healthy Diner – How to Eat Right and Still Have Fun”®, which is available on her blog, “Food and Health with Timi Gustafson R.D.” ( http://www.timigustafson.com), and at amazon.com. You can follow Timi on Twitter at http://twitter.com/TimiGustafsonRD