In the late 18th century, Napoleon Bonaparte offered a reward to whomever could figure out how to safely preserve food for his traveling army. Nicholas Appert set to work, and found the solution (although 15 years later), sealing heat-processed food in glass jars with wax. In 1810, Englishman Peter Durand was the first to preserve food in a sealed tin can.
Canning is an important way to keep foods safe and allows us to enjoy their nutrients even when they’re out of season. But new evidence indicates that with so many fresh options available year-round, it’s smart to avoid canned foods when possible. A recent study in Food and Function examined the transfer of zinc oxide (ZnO), a substance found in the lining of some canned foods, to the foods themselves and explored whether that has an impact on your ability to absorb nutrients.
Examining canned corn, tuna, asparagus and chicken, they found those foods contained 100 times the daily dietary allowance of zinc! They then found that exposing cells in the gut to even low levels of ZnO did interfere with their ability to absorb nutrients.
Past studies have linked eating highly processed food, which often comes in cans (think SpaghettiOs), to higher risks of cancer and weight gain. Now it seems these canned foods also may keep you from getting the nutrients you need, even when you eat nutrient-rich food! So whenever you can, kick the can off your shelf in favor of fresh produce, unprocessed foods and even frozen foods.
Mehmet Oz, M.D., is host of “The Dr. Oz Show,” and Mike Roizen, M.D., is chief wellness officer and chair of Wellness Institute at Cleveland Clinic. To live your healthiest, tune into “The Dr. Oz Show” or visit www.sharecare.com.