Tuesday, September 15, 2015

Cheese & blood cholesterol

Many years ago I worked for the Heart Foundation and it was standard practice to tell anyone newly diagnosed with high blood cholesterol that they had eaten their last piece of cheese. For some I had taken away their reason to live. Between the sobs they would plead: “Just one last cheese toasty, please.” I just had to shake my head and call for the onsite counsellor.

Now there is review article suggesting that I have been the cause of much undue concern.
Beyond saturated fat
The human creation of cheese was a very clever way to concentrate milk and increase it’s shelf life, making it a reliable food source. The enduring problem was its relatively high salt and saturated fat content, a combination that would raise both blood pressure and blood cholesterol. Dutch researchers have now looked at all the randomised control trials, most with a crossover design, comparing cheese and other foods such as butter, milk and tofu.

The authors say: “The results consistently showed that that the effects of cheese on lipids and lipoproteins were different than expected from the fat content.” What they are saying is, although cheese is high in saturated fat it didn’t raise cholesterol as predicted. Why? The abundant calcium in cheese could be binding with fats to reduce their absorption. Previous studies have observed that dairy calcium minimises a rise in blood cholesterol. The phospholipids in cheese may also be attenuating any rise in blood cholesterol.

Hard or soft?
As far as I can gather, the research was done primarily on hard cheese, such as cheddar. There wasn’t a study on soft cheeses like camembert. I suspect that soft cheeses would also have little effect on blood cholesterol, although that suspicion may be biased due to my absolute delight in enjoying an excellent brie or camembert.

What does it all mean?
In nutrition there are many questions. It would be perfect if we could say cheese is good or bad for the heart. It depends. Even now the Heart Foundation is not a big fan of full cream dairy products. They tell us to cut them out and replace them with reduced-fat or low-fat versions. Let’s be honest, reduced-fat cheese is dreadful, akin to eating the soft plastic casings for mobile phones.

So do this. Buy cheese. Buy really nice cheese. Like triple cream camembert. Enjoy it. Just don’t eat too much.

Dairy & heart disease: a lower risk than previously thought

It has been clear for a long time that not all saturated fats act the same. Saturated fats come in a range of lengths, dictated by the number of carbon atoms in the fatty acid chain. Look, it’s a chemistry thing, and 93% of people never did chemistry at school, let alone university. You can go to everyone’s friend Wikipedia if you want a quick refresher on saturated fat. Better still, just keep reading the next paragraph.

Let me just say, there is mounting evidence that dairy foods aren’t the evil forerunner to a life of wheezing or chest pain or drop dead heart attacks. In sensible amounts, milk, cheese and yogurt are a pretty good source of calcium, riboflavin and protein. The authors of one review paper regarding dairy and the risk of heart disease say they “could find no consistent evidence that dairy food consumption is associated with a higher risk of coronary heart disease.” There are many reasons why no clear link was seen in the studies:
  1. Great variation in the study designs
  2. Insufficient consideration of other lifestyle factors associated with heart disease
  3. More low-fat dairy foods became available over the last 40 years making it difficult to compare a study from the 1970s to one in the 2000s
  4. Often there was no distinction between high-fat and low-fat dairy products
Welcome to the world in which I live, where nutrition is not as simple as we would like, and our advice will vary from person to person. Look, I drink skim milk and eat good cheese. A contradiction? A bet each way? Or is it fine because I eat loads of fruit, vegetables, legumes, mushrooms and wholegrains? Whatever, I’m happy.

A2 milk
More recently there has been debate about the type of protein in milk and its influence on health. Milk with A1 beta-casein protein may cause more gut pain and looser stools than milk that exclusively contains A2 beta-casein. In fact, if someone has a milk intolerance then lactose may not be culprit, but A2 casein.

There is now a recent review that anyone can download. It is still early days in research terms, although the authors believe they have a compelling case for all dairy cattle to be the type that produce only A2 milk.