Foods in foreign lands are often different than what US residents typically eat, but even the fare at decidedly American chains like McDonald’s or Burger King may not taste the same — and now a new study reveals why.

Dr. Norman Campbell, a University of Calgary professor of medicine and community health, and his colleagues examined the nutritional data chains like McDonald’s, Burger King, Domino’s, Kentucky Fried Chicken, Pizza Hut and Subway provided for consumers in the US, UK, Canada, New Zealand, Australia, and France.

The results? Food in the US and Canada generally has more salt than the same items sold elsewhere.

While the salt in a McDonald’s Big Mac didn’t vary much between countries, the restaurant’s Chicken McNuggets in the US and Canada have almost three times as much salt per serving as those in the United Kingdom. In addition, the Subway club sandwiches offered to diners in the US, Canada, and New Zealand contain about twice as much sodium as those sold in France.

Excess sodium has been linked to heart attacks and strokes, but some chains have resisted lowering the sodium amounts in their offerings, saying doing so would make them unpalatable — something Campbell discounts.

“These companies can reduce the salt in their foods because they are doing it,” he said. “Decreasing the salt content of fast foods is certainly technically feasible and it would improve health and save billions annually in health care costs.”