COMMENT: Milk, cheese and yoghurt lovers got good news this week: People who eat dairy have a lower risk of heart disease than those who don't.
The global observational study, published in The Lancet, of more than 130,000 people in 21 countries found dairy consumption of around three servings per day is associated with lower rates of cardiovascular disease and mortality, compared to lower levels of consumption.
What's more it didn't matter if the dairy products were low fat or full fat; the results were similar: Three servings of dairy a day — a cup of yoghurt; a glass of milk or a small slice of cheese — is linked with better health than consuming little or no dairy.
The story wasn't quite so positive for butter, where higher consumption was associated with a slightly higher risk of heart disease, although this was described as "not significant".
This research is an interesting addition to a growing body of evidence suggesting dairy is good for us, and that the saturated fat in dairy might not be harmful in the way that saturated fat in, say, processed meat is.
But since it's an association, not a causal link, we can't say from this "eat dairy to lower your risk of heart disease". And we can't say "saturated fat is good", either, although you might not think so from some of the headlines.
What's highlighted here is the distinction between single nutrients (such as fat or carbohydrate) and whole foods. We eat food, not nutrients, and foods are a whole lot more complicated than nutrients, and a whole lot more difficult to understand.
The researchers note this in their paper: "Dairy products are a diverse food group that include fermented and cultured products with many different nutrients, and their impact on health outcomes cannot be characterised fully by the presumed effect of one nutrient on a single biomarker. Even saturated fats are a diverse group, and their effects might vary depending on the content of a specific saturated fatty acid in various foods."
They point out they don't know what it is in dairy that's having these effects, and highlight the need to study direct associations of foods and health "rather than relying on assumptions based on isolated ingredients in such foods".
In other words: There's lots still left to learn. Which is the great thing about science: It's never done-and-dusted, we-know-this-for-sure. One piece of research adds to what has gone before.
So what does this add to what we as consumers know about milk, cheese and yoghurt? It reassures us that these are good foods — full fat or low fat. We should choose what suits us and our individual situations. If we like dairy foods and don't have an allergy or intolerance to them, they're good foods to consume regularly. And they have other benefits aside from any potential effect on heart disease risk. Not the least of which is that they're delicious.
• Niki Bezzant is editor-at-large for Healthy Food Guide www.healthyfood.co.nz