(NEW YORK) -- Sandwiches have long been a staple on American lunch menus, piled high with deli meats and toppings tucked between fluffy yet hearty bread.
While there are certainly ways to make sandwiches more healthy, some may still kick nutrition to the curb.
As the Wall Street Journal reported Tuesday, experts say the bread that holds deli sandwiches together is an issue when made with refined flour, which can raise blood sugar and insulin.
Dr. Dariush Mozaffarian, a cardiologist and professor of nutrition and medicine at Tufts University who was cited in the Journal's report, told ABC News' Good Morning America that eating processed meat is also "bad for your health."
"On average, eating about a serving [of processed meats] per day is associated with about [20%] higher risk of diabetes ... and about [40%] higher risk of heart disease," Mozaffarian said, calling sandwiches a "heart bomb."
According to research published on the National Institutes of Health website, sodium and preservatives in processed deli meat can increase the risk of cancer, heart disease and diabetes.
There are also hidden sugars in many condiments from ketchup, with an average of 4 grams of sugar per tablespoon, to barbecue sauce, which has 6 grams per tablespoon.
Sodium and saturated fats can also be a problem.
According to data gathered by the Journal, sandwiches are the number one source of sodium and saturated fat in Americans' diet, making up one-fifth of our daily sodium intake and 19% of our daily saturated fat calories.
The American Meat Institute told ABC News in a statement that "meat and poultry processors understand that people have different health and wellness goals and needs" and "have been actively engaged in efforts to reduce sodium."
ABC news medical contributor and emergency room doctor Darien Sutton said that "we have to make better choices, learning more and getting more understanding of the value of our diet in relation to our physical health."
"We can consider things ... that might just be better overall, reducing saturated fat, added sugar and also just [fewer] calories," Sutton said.
For example, Sutton suggested swapping out white bread for something with a whole grain.
"Whole grain is a great source of fiber. It has antioxidants in it. Also, it's associated with lowering that [low-density lipoprotein], or that bad cholesterol," he explained.
Sutton also said to swap out processed deli meat, which can be high in nitrates, and substitute it with something like chicken.
"It's a hearty meat so it's going to keep you more full," he said. "Instead of American cheese, we can switch it out for mozzarella or Swiss cheese. Mozzarella cheese is a great source of a natural probiotic great for our gut health."
Finally, he tackled condiments, saying that eliminating mayonnaise alone can cut a lot of calories.
"Instead of mayonnaise -- there's no real substitute for it -- but if you want the texture, I love hummus," he said, adding that it's a "great source of healthy plant-based protein and fiber."
When ordering a sandwich out at a restaurant or deli, he suggested asking them to add veggies first, skip more meat and stick with a whole grain bread.
Ultimately, making consistent healthy choices is key. Always talk to a health care professional when starting a new diet to make sure you are meeting your nutritional requirements, especially if you have a chronic disease.