Eating Parmesan cheese can be an effective way to get probiotic bacteria into your gut, according to a new study from Italy.
The authors looked at the bacteria in the guts of cows and their milk and tracked how these get into us and colonise our guts via eating Parmesan cheese.
The authors found that Parmesan cheese contains beneficial bacteria including a wide range of different types particularly in the bifidobacteria and lactobacilli families.
Other studies show us that these ones promote health, from better weight and mental health, to better immune system and heart.
Bacteria that can promote health in the animal or human they reside in are known as probiotics. Often people consume these in supplement form to colonise the gut for health benefits. But research such as this study is teaching us that some foods can have a far wider and varied profile of bacteria that changes with each batch, than static manmade pills.
Parmesan cheese is made with unpasteurised milk, so beneficial bacteria don’t get killed by being heated. This can happen when a cheese is pasteurised. Many mass marketed cheeses don’t contain probiotic bacteria because these have been killed during processing.
The study showed that a particular bacteria in Parmesan called Bifidobacteria mongoliense survives well - colonising the human gut, without being killed off by stomach acid. Intriguingly the humans in the study who ate 45g of Parmesan cheese daily for a week alongside a glass of pasteurised milk, had better colonisation than those eating just Parmesan and no milk. The researchers wonder if there are substances in milk – even if pasteurised - that generally help with the seeding of bacteria from Parmesan.
The cows in the study were from five different farms in the regions of Parma and Reggio Emilia where Parmesan cheese is made.
The study found that beneficial bacteria from the cows’ guts, and the litter they dwell in, are present in the milk the cows produce and the Parmesan cheese made from it, and some bacteria in the cheese survives well in the human gut too without being killed off by our stomach acid.
Interestingly the bacteria in the cows’ guts is thought to travel to the cows’ udders systemically and get into the milk, and then the cheese made from it. Friendly bacteria from the litter they dwell in (probably from their stools) gets into the milk too probably as their mammary glands have contact with it. This tells us that the way cows are housed and looked after in comfort is important to developing lots of friendly bacteria in their milk.
The study was funded by the European Union.
