Should we eat dairy? Understanding the dairy matrix
My wonderful Grandma, who lived to 94 despite eating all the ‘wrong’ foods, taught me a hugely valuable lesson – you often can’t trust nutrition fads. She never traded butter for margarine and, despite the warnings of her cardiologist (who she outlived) she never gave up her favourite triple cream brie.
Nutrition is a fast-moving target and it can often feel overwhelming trying to keep up with what are the ‘right’ foods to eat. In the wake of this confusion, I’m guided by the wisdom of previous generations. I believe that we shouldn’t turn our backs on foods that our great grandparents happily enjoyed, including cheese, butter, yoghurt and milk.
One thing I think we are finally getting right in the world of nutrition is to look at the effect of food in its entirety (known as its matrix), rather than the reductionist approach of just breaking it down into its various nutrients.
While a food’s precise nutrient content is interesting, it can’t always accurately predict its health properties. This newer, holisitic matrix approach recognises that the nutrients in food are housed in complex physical structures that play a role in determining their impact on our health.
For example, we now know that dairy foods – despite containing some saturated fat – have a uniquely positive impact on our health that cannot be mimicked. They play a role in weight management, bone health, muscle building and repair, heart health, and even a reduced risk of type 2 diabetes and high blood pressure. This is thanks to their distinctive food matrix that simply can’t be imitated – even by fortified alternatives.
A good example of the matrix effect is looking at how calcium is absorbed from dairy versus supplements. Interestingly, research has shown that calcium from dairy has greater effects on bone mineral density (an indicator of bone strength) than equivalent calcium supplements. Researchers have suggested that it may be the protein and lactose in dairy that enhances calcium balance by promoting absorption.
We also know that milk is an exceptional drink when it comes to muscle growth and – in it’s whole food form – it performs better than other protein sources for achieving post-workout muscle gains (see for example this study comparing milk to soy milk). Instead of investing in expensive protein powders, I usually just grab a smoothie after training because I know that milk and yoghurt contain a matrix of nutrients, high-quality proteins and bioactive factors which interact to help me both build and repair muscle after exercise.
The matrix approach is also useful in understanding the relationship between dairy and heart health. Despite containing some saturated fat, dairy doesn’t seem to increase heart disease risk and it may even have a protective effect (this study suggests eating cheese can actually lower heart disease risk). Interestingly, the Heart Foundation has changed its previous advice that Australian adults opt for reduced-fat milk and it now recommends that ‘milk, yoghurt and cheese can be eaten as part of a heart-healthy diet’, even full-cream options for healthy Australians.
When I think back to my childhood, I feel so grateful that whole milk, yoghurt and cheese was always on the menu. Knowing how those foods helped build stronger bones for me before I hit my peak bone mass in my early twenties (so critical for avoiding osteoporosis later in life), as well as set me up for a whole raft of health benefits that science is only now fully recognising, I now make sure that my own children have that same advantage. Yoghurt and kefir play a particularly central role in their diet because I know that they’re also doing their gut microbiome the world of good thanks to their billions of probiotics.
It’s refreshing to see the world of nutrition start to take a more holistic, nuanced approach to understanding the health impact of food. Ultimately I think variety is the answer – enjoying a wide range of whole foods helps to ensure that we’re not getting too much or too little of any one of them. This is something previous generations seemed to understand and it’s certainly a wisdom that I would like to see passed on to future generations.