If you think a vegan meal can't possibly be as filling as a steak, you might be surprised to hear that protein from mushrooms is actually just as likely to fill you up as protein from meat.

Plant-based diets have been growing in popularity. The World Health Organization and the United Nations have been advocating vegetarian and vegan diets for years, to protect against obesity and encourage less energy-intensive farming.

For those still concerned about whether they could stomach a vegan or even just a vegetarian diet, a recent small study has found that mushroom protein can do the job perfectly well.

A total of 32 people were given two servings of mushrooms or of meat to eat every day for ten days. On the first day they were given a mushroom or meat breakfast, and rated how full they felt several times in the following hours.

Then after three hours, they were given a help-yourself lunch where the scientists recorded how much they ate. Then they were sent home and given either mushrooms or meat to work into their diet for the next nine days.

At the all-you-can-eat lunch there was no immediate difference between the mushroom eaters and the meat eaters. But over the following days, people on the mushroom regime reported being less hungry, fuller for longer and found themselves planning smaller meals.

But overall, the mushroom eaters didn't eat more or less food than the people on the meat regime, the researchers found. So it seems that eating mushroom protein is at least as good as eating meat protein.

However, one potential drawback was that to get enough mushroom protein the volunteers had to eat more mushrooms than meat – 226g of mushrooms to get the protein versus 28g meat. Many vegetarian and vegan foods use extracted mushroom protein as a basis, decreasing the number of mouthfuls needed to get the same protein content.

The experiment was a small-scale one, so it's not going to be the final word on mushroom protein. But either way, the argument that meat protein is inherently more filling than meat-free protein doesn't appear to stand up.