Why avoid canned tomatoes? Unpacking the health risks in your pantry

October 5, 2025 •

4 min read

Did you know that the acidity of tomatoes can cause chemicals from the can lining to leach into your food? This is a major reason why avoid canned tomatoes is a growing concern for those focused on a clean diet, raising important questions about the safety of our pantry staples.

Quick Summary

This article explores the health concerns associated with canned tomatoes, from endocrine-disrupting chemicals found in linings to potentially high sodium levels. It delves into the risks, compares them with fresh and jarred options, and offers safer alternatives for cooking and consumption.

Key Points

Chemical Leaching: Acidity in canned tomatoes can increase the leaching of chemicals, such as the endocrine-disrupting BPA, from the can's epoxy lining into your food.
Questionable 'BPA-Free' Alternatives: Many manufacturers use substitute linings that may contain other endocrine-disrupting chemicals, like BPS, with less known health effects.
High Sodium Content: Salt is commonly added as a preservative and flavor enhancer in canned tomatoes, potentially contributing to high blood pressure.
Nutrient Compromise: While cooked tomatoes have more bioavailable lycopene, the canning process involves high heat that can degrade other vital nutrients like Vitamin C.
Superior Alternatives: Opting for tomatoes in glass jars, aseptic cartons, or using fresh produce eliminates the risk of can-lining chemical exposure and allows for complete control over sodium levels.
Flavor Loss: The metallic taste sometimes found in canned tomatoes, and the often-bland flavor compared to fresh, can negatively impact your finished dish.

The Chemical Concerns: BPA and Beyond

For many years, the lining of most food cans contained Bisphenol A (BPA), a chemical used to prevent corrosion. A growing body of research has classified BPA as an endocrine disruptor, meaning it can interfere with the body's hormonal system. Studies have suggested a link between BPA exposure and a range of potential health issues, including reproductive problems, metabolic disorders, and an increased risk of certain cancers. The high acidity of tomatoes is particularly concerning, as it can accelerate the rate at which BPA leaches from the can lining into the food.

Facing consumer pressure, many manufacturers now offer 'BPA-free' cans. However, this switch is not without its own set of questions. Many of these alternative linings contain substitute chemicals, such as Bisphenol S (BPS), which have not been as extensively studied as BPA but are also suspected to have endocrine-disrupting properties. For those with long-term health concerns, the simple act of avoiding traditional canned options eliminates the worry over these substitute chemicals altogether.

Endocrine Disruptors: A Broader Look

It's important to understand that BPA and related chemicals are just a part of a larger class of endocrine disruptors (EDCs) found in food packaging. Beyond can linings, EDCs can be present in plastic packaging and even recycled paper products. For acidic foods like tomatoes, the risk of chemical migration is heightened regardless of the specific packaging material. Choosing inert packaging, such as glass jars or aseptic cardboard boxes, can significantly reduce this exposure.

The High Sodium Problem

One of the most immediate and controllable reasons to avoid canned tomatoes is their often-high sodium content. Salt is frequently added to canned goods, not just for flavor but also as a preservative. A single serving of canned tomatoes can contain a significant portion of a person's recommended daily sodium intake, with some products containing 100 to 300 milligrams per serving.

Health Implications: Regular consumption of high-sodium foods is linked to high blood pressure, increasing the risk of cardiovascular disease, kidney damage, and stroke.
Checking Labels: While many brands offer 'no salt added' or 'low sodium' versions, it's crucial to check the nutrition panel carefully, as the salt content can vary dramatically between products.

Fresh vs. Canned: A Nutritional and Flavor Breakdown

When evaluating the nutritional profile of tomatoes, there are notable differences between fresh and canned versions. While canning can increase the bioavailability of lycopene, a potent antioxidant, it often comes at the cost of other nutrients and flavor.


Feature	Canned Tomatoes	Fresh Tomatoes	Potential Risk/Benefit
Chemical Exposure	Potential for chemical leaching (BPA/BPS) from can linings.	Minimal chemical risk, depending on farming practices.	Risk: Endocrine disruption from chemicals like BPA.
Sodium Content	Often contains high levels of added sodium for preservation and flavor.	Naturally low in sodium.	Risk: High sodium intake linked to hypertension.
Taste	Can have a metallic taste and often lacks the vibrant flavor of fresh, ripe tomatoes.	Offers a fresher, more vibrant taste, especially when in season.	Benefit: Better flavor profile, not compromised by metallic can taste.
Lycopene	High in bioavailable lycopene due to the cooking process.	Contains lycopene, but it's less bioavailable than in cooked forms.	Benefit: Higher antioxidant content after processing.
Vitamin C	Some Vitamin C is lost during the heat processing of canning.	High in Vitamin C, especially when ripe and consumed fresh.	Risk: Lower vitamin content after processing.

Healthier Alternatives to Canned Tomatoes

Choosing healthier alternatives is easy and often results in better-tasting food. A simple switch can mitigate the risks associated with canned products while still providing the convenience you need.

Fresh Tomatoes: The gold standard. If you're fortunate enough to have access to ripe, in-season tomatoes, cooking with fresh is the best option for both flavor and nutrient content. When tomatoes aren't in season, you can still find good-quality fresh options, especially for sauces.
Jarred Tomatoes (Passata): Opt for tomatoes sold in glass jars. Since glass is inert, there is no risk of chemicals leaching into the contents. Be sure to check the label for added sodium or preservatives.
Aseptic Cartons: Another excellent option for avoiding can linings, aseptic packaging (like those from brands such as Pomi) is a safe alternative. These products are typically just tomatoes and are often labelled BPA-free.
Thinned Tomato Paste: For a quick fix, tomato paste thinned with water or broth can be a great substitute. It offers a concentrated tomato flavor without the additives and can be easily adjusted to your preferred consistency and sodium level.
Frozen Tomatoes: If you have a bounty of fresh tomatoes in season, consider freezing them. This preserves their flavor and nutrients for later use in sauces, soups, and stews.

Making an Informed Choice for Your Diet

While canned tomatoes offer undeniable convenience, the potential health risks from can linings and excessive sodium deserve careful consideration. Taking a moment to evaluate your options can lead to a healthier diet and greater peace of mind. By opting for glass jars, aseptic cartons, or fresh produce, you can enjoy the rich flavor of tomatoes without the potential downsides. Making small, conscious choices about food packaging is a simple yet effective way to support your overall well-being. For more information on avoiding harmful chemicals, visit the Environmental Working Group's website. https://www.ewg.org/news-insights/news/bpa-update-tracking-canned-food-phaseout

Conclusion

Ultimately, understanding the reasons behind why avoid canned tomatoes isn't about fear, but empowerment. It's about being aware of the substances that can enter our food and choosing cleaner, safer alternatives. While the benefits of canned tomatoes—like high lycopene—are sometimes touted, the potential exposure to endocrine disruptors and high sodium levels suggests a cautious approach is warranted. A balanced perspective that favors fresh, frozen, or properly packaged options ensures you get the best nutrition possible.

Frequently Asked Questions

BPA (Bisphenol A) is a chemical historically used in the epoxy resin lining of food cans. It is a known endocrine disruptor that can interfere with hormonal systems, and its leaching into food is accelerated by acidic contents like tomatoes.

Not necessarily. While BPA-free cans eliminate BPA, some use substitute chemicals like BPS, which are also suspected to have endocrine-disrupting properties. Consumers should research the specific lining used by the manufacturer if concerned.

Yes, many canned tomato products contain high levels of added sodium for preservation. Consuming too much sodium can lead to high blood pressure, increasing the risk of cardiovascular disease.

While canned tomatoes do contain more bioavailable lycopene than fresh ones due to the cooking process, the benefits must be weighed against potential exposure to endocrine disruptors and high sodium levels. Safer alternatives like fresh tomatoes can provide a better overall nutritional profile.

Excellent alternatives include fresh tomatoes, tomatoes packaged in glass jars (passata), or products in aseptic cartons. These options avoid the chemical risks associated with can linings and allow for more control over added ingredients like salt.

It is not safe. Dented, leaky, or swollen cans should be avoided, as they can indicate potential contamination, including botulism. If a can is compromised, its contents should not be consumed.

Yes. The high acidity of tomatoes is a major factor that can increase the rate at which chemicals from the can lining, such as BPA, migrate into the food. This is less of a concern with inert packaging like glass.

Yes. Some products may contain other preservatives like citric acid or calcium chloride. Checking the ingredients list is the best way to be aware of what is in your food.