- A study of middle-aged, overweight adults in Ireland suggests that eating cheese isn't bad for your cholesterol. In fact, there's some evidence full-fat cheese may have a protective effect on the heart.
- Scientists think there might be something special about the way calcium and protein is arranged in cheese that creates this effect.
- They call it the "cheese matrix."
Cheese fans have long felt that enjoying some protein-packed, fatty cheese is the ticket to a better life.
Now science is starting to back them up.
Cheese is high in saturated fat, which is often considered dangerous for your heart. Most nutritionists say we should only nibble limited doses of the heart-clogging fat.
But nutrition experts around the world are discovering in study after study that dairy may not be as bad for your heart as once thought. Certain kinds of fatty dairy, including cheese, could even help lower cholesterol, though more robust studies of larger groups of cheese-eaters are needed to know for sure.
In the latest study, researchers found that middle-aged, overweight adults who ate full-fat cheddar cheese reduced their cholesterol more than peers eating reduced fat cheese or butter, suggesting there's something special about the way old-fashioned cheese works inside the body. (The study was funded, in part, by Irish dairy companies, but the researchers reached their conclusions independently.)
Study participants ate huge amounts of full-fat cheddar cheese for six weeks straight
The food scientists behind the latest cheese investigation think they have zeroed in on something special about the aged, fatty food that makes it better for cholesterol than other dairy products.
This is what they call the cheese matrix: the specific way that nutrients like protein and calcium are arranged inside the yummy blocks.
"I suppose the 'cheese matrix' does make it sound very mystical," lead study author Emma Feeney, who studies human nutrition and metabolism at University College Dublin, told Business Insider. "It's really not, it's just a fancy word for the overall structure."
Feeney's study of 164 overweight, middle aged Irish adults, published in the American Journal of Clinical Nutrition earlier this month, found that participants who incorporated blocks of full-fat Irish cheddar cheese in their diets, while limiting other dairy intake to just two ounces of milk per day, didn't gain weight.
Instead, participants lowered both their total cholesterol and levels of so-called "bad" LDL cholesterol. They ate a ton of cheese while doing it, too: 120 grams a day, or more than half a standard Irish cheese block. It's the kind of cheese block meant to serve an entire household of cheese lovers.
The findings go hand in hand with another study published in July, which followed more than 2,900 American adults for more than two decades. That study found people who consumed full-fat dairy had no greater risk of dying from any cause, including heart attacks, than anyone else.
"We need to stop thinking about foods in terms of their fat and their saturated fat content, and thinking about them as a whole food," Feeney said.
During the study, Feeney broke participants down into four groups. The first group were the full-fat cheese eaters, ingesting the whopping 120 grams of cheddar a day. A second group of study participants ate reduced-fat cheddar and butter. A third ate butter in addition to protein powder and calcium supplements (mimicking the nutritional value of cheese), and a fourth group had no cheese at all.
Full-fat cheese eaters reduced their cholesterol most effectively, while the reduced-fat cheese eaters and butter-plus-supplement group lowered their cholesterol a bit, but not as well.
The study authors think this might be evidence that calcium and protein in cheese, eaten as a whole food and not as a supplement or reduced-fat diet food, may best reduce the artery-clogging effects of butterfat on the body.
There's a big caveat, however. Since so many people dropped out of the no-cheese-allowed group (who wants to volunteer to not eat cheese for six weeks?) the study numbers in that category aren't robust enough to know for sure that eating cheese can actively help reduce cholesterol, compared to not eating any cheese at all.
"We wouldn't be able to conclusively say that from these results," Feeney cautioned. "But certainly, it does look that way."
What's so special about cheese?
Nutritionists from around the world are starting to notice that people who eat more fermented dairy products, like cheese and yogurt, are at a lower risk for developing heart disease and Type-2 diabetes. While the reasons why aren't fully understood, there are a couple big clues.
The first has to do with dairy protein.
Casein, a complete protein in cheese and milk, digests slower than most other animal proteins. Casein is a big part of the protein component in dairy: in sheep's milk cheese, for example, anywhere between 76-83% of the proteins are casein.
Cheese is also more fat-concentrated than milk, because cheese-making separates liquid whey from curds, adding in bacteria and converting milk sugars into lactic acid, making the product less watery.
In the case of cheddar, there's a "cheddaring" process in which salt is added and the product is stacked, turned, and aged. During this time, bacteria break down the proteins in cheddar cheese, giving it a characteristically chewy texture and cheesy flavor.
But not everyone thinks this aged dairy protein is good for us.
Thomas Colin Campbell, biochemist and author of The China Study, has taken a critical view of casein and spent decades studying how plant-based diets are better for health than animal products.
Campbell does acknowledge, however, that breaking nutrition down into individual components in food doesn't create a clear picture of how our bodies process what we eat.
"Investigating the independent effects of one substance at a time, as with casein, is very incomplete and misleading, even though such information can be very valuable as a stepping stone to a larger truth," he wrote on his blog.
Don't break the membrane
There is one more potential explanation for why cheese fat may be better for us than butter fat, and it lies in something called the milkfat globule membrane. The "MGM" is a tiny outer shell that surrounds individual fatty acid droplets (lipids) in milk, and it isn't preserved in butter.
"When you make butter, you break that membrane up, and it's actually drained off," Feeney said.
(Other MGM-rich dairy, like cream, contains twice the milkfat globule membranes of butter per gram of fat, and won't raise LDL cholesterol levels, either.)
Despite the seemingly good news about cheese and cholesterol, Feeneysays moderation is still key:
"We would not recommend that people go off and eat 120 grams of cheese every day," she said. But "a piece of cheese, the recommended portions of cheese, are not going to do you any harm."