Fast-food chains are jumping on the meatless-burger bandwagon, making deals with companies that make plant-based "meat," such as Beyond Meat and Impossible Foods.

While many customers assume that these meatless burgers are healthier, the nutritional info tells a different story.

In most ways, plant-based burgers are similar to fast-food icons — but they tend to contain significantly more sodium.

Fast-food chains are jumping on the plant-based-burger trend. But many people are wondering whether these meat-free options are actually healthier than the originals.

In recent years, chains such as Carl's Jr., White Castle, and Burger King have announced partnerships with companies that make plant-based "meat," such as Beyond Meat and Impossible Foods.

Nutrition is a major reason that people are giving plant-based burgers a try, according to a recent Barclays report.

Read more: 3 factors are driving the plant-based 'meat' revolution as analysts predict companies like Beyond Meat and Impossible Foods could explode into a $140 billion industry

However, Barclays found that the new burgers were not necessarily the nutritional home run that some people might expect.

Here's how Beyond Meat's and Impossible Foods' burgers compare with their fast-food counterparts (the highest total in each column is bolded):

When it comes to calories, fat, and protein, the two options are pretty similar.

The plant-based burgers have less cholesterol. While the Whopper, for example, has 90 milligrams of cholesterol, the Impossible Whopper has just 10.

However, the plant-based burgers tend to have more sodium than their meaty counterparts. The Impossible Whopper has 1,240 milligrams of sodium — 260 more than the original Whopper. The Beyond Famous Star has 340 more milligrams of sodium than the burger it's based on.

Barclays concluded that when it comes to plant-based burgers, many are "thinking that they are healthier than what they really are."

Beyond Meat and Impossible Foods are continuing to tweak their recipes. Earlier this year, Impossible Foods launched the Impossible Burger 2.0, designed to be substantially healthier (and tastier) than the original, with less fat and sodium.