Are Canned Tomatoes Good or Bad?
Worried about the nutritional value and food safety of canned goods? We asked an expert to weigh in on this pantry staple and whether you should stock up.
Many of our readers have expressed concern over using canned goods, including BPA risks, nutritional value and of course, food safety. So, how safe is this pantry staple? We've got the scoop.
Both canned and fresh tomatoes are equally nutritious. Both also count toward your daily recommended amount of vegetables; the CDC says only one in 10 adults meets the recommended daily amount. According to a 2015 study, folks who consumed six or more canned items a week were more likely to have diets high in 17 essential nutrients compared to those who consumed canned foods two or fewer times a week. In addition, folks consuming six or more canned items a week consumed a high amount of nutrients that most Americans tend to under consume, including calcium, iron, vitamin D and potassium, compared to those who consumed two or fewer canned items per week.
In addition, canned tomatoes provide lycopene, a phytochemical or natural plant compound that provides health benefits (and gives tomatoes their gorgeous hue). The antioxidant lycopene has been shown in over 700 studies to have a positive impact on breast cancer, heart cancer, inflammation and prostate cancer. Canned tomatoes have much more lycopene bioavailable compared to fresh tomatoes, which means you get more. When tomatoes are cooked, as they are in all types of processed tomatoes (such as cans, jars, sauces, salsa and ketchup), the lycopene is even more available to your body. This is because the cooking opens up the cell walls in the tomato plant to allow the lycopene to be absorbed into your body.
No time to blanch and peel tomatoes for homemade sauce, chili or soup? That’s when the canned varieties come in handy. They’re especially useful during the winter months when tomatoes aren’t in season, and they can be stored in your pantry for up to 18 months.
Despite concerns that there is BPA in the lining of cans of tomatoes, the USA Canned Tomato Industry stopped using BPA years ago. Here’s a little background on BPA:
Bisphenol-A (or BPA) is a synthetic compound used since the 1960s to make certain plastics and resins. The plastic coating created by BPA serves as a lining in metal cans to protect the cans from corrosion or pitting when exposed to acidic foods, like tomatoes. Ultimately, the lining protects the customer from exposure to metals, which can happen when acidic foods are in contact with unlined metal cans.
BPA is thought to be similar to estrogen, and it may have the ability to disrupt the function of other hormones in the body and possibly negatively impact the brain. Many of the studies indicating risks from BPA were based on small studies using rodents, not humans. A two-year government study found that even higher doses of BPA had only minimal effects, which could have occurred by chance, as most folks have detectable levels in BPA in their urine. According to the FDA, based on its most recent safety assessment, BPA is safe at the current levels occurring in food.
Although no restrictions have been made with regard to the use of BPA, the U.S. canned tomato industry has removed BPA from its products. If you’re concerned about BPA in your food, many companies label their products as “BPA-free,” and even though they may not all be labeled, virtually all canned tomatoes have removed BPA from their linings.
Canned tomatoes often contain salt, which adds flavor and acts as a preservative. If you check the label, you’ll typically find anywhere from 100 to 300 milligrams of sodium per serving — that’s 4% to 13% of the daily recommendation. Look for “no salt added” versions to reduce sodium by a third. You can also find “low sodium” varieties at your local market.
You may also find preservatives like citric acid and calcium chloride on some products. Both are considered safe to eat. Citric acid helps preserve color, while calcium chloride helps keep diced tomatoes nice and firm. You can also opt for boxed tomatoes (like Pomi) — they're BPA-free, and the only ingredient listed on the label is tomatoes.
Botulism is a concern with all canned goods, specifically if home canning is used. There has not been a case of botulism in canneries in the U.S. for many, many years. If you choose to can tomatoes at home, then select a reputable recipe and follow it exactly.
If you buy canned tomatoes at the store, make sure to avoid buying cans that are dented, leaky, rusted or swollen. Store the cans in the pantry at room temperature out of the sunlight and follow the “use by” date. Once opened, transfer the contents of the can to a refrigerator-safe container and store for up to four days.
There are more pros than cons to using canned tomatoes. They’re quick, convenient and full of nutrients. They’re also a perfect choice for soups and sauces when fresh are expensive or out of season. So stock up on your favorite canned tomato goodies and get cooking!
Toby Amidor, MS, RD, CDN, is a registered dietitian and consultant who specializes in food safety and culinary nutrition. She is the author of The Greek Yogurt Kitchen: More Than 130 Delicious, Healthy Recipes for Every Meal of the Day.
*This article was written and/or reviewed by an independent registered dietitian nutritionist.